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Objective: Multidisciplinary care with free, rapid, and on‐site bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) dispensation may improve health outcomes among migrants living with HIV. However, models for rapid B/F/TAF initiation are not well studied among migrants living with HIV, and an understanding of how social determinants of health (SDH) may affect HIV‐related health outcomes for migrants enrolled in such care models is limited. Methods: Within a 96‐week pilot feasibility prospective cohort study at a multidisciplinary HIV clinic, participants received free B/F/TAF rapidly after care linkage. The effects of SDH (i.e., birth region, sexual orientation, living status, education, employment, French proficiency, health coverage, use of a public health facility outside our clinic for free blood tests, and time in Canada) and other covariates (i.e., age, sex) on median time to antiretroviral therapy (ART) initiation and HIV viral undetectability from care linkage were calculated via survival analyses. Results: Thirty‐five migrants were enrolled in this study. Median time to ART initiation and HIV undetectability was 5 days (range 0–50) and 57 days (range 5–365), respectively. Those who took significantly longer to initiate ART were aged <35 years, identified as heterosexual, had less than university‐level education, or were unemployed. No factor was found to significantly affect time to undetectability. Conclusion: Despite the provision of free B/F/TAF, several SDH were linked to delays in ART initiation. However, once initiated and engaged, migrants living with HIV reached HIV undetectability efficiently. Findings provide preliminary support for adopting this care model with migrants living with HIV and suggest that SDH should be considered when designing clinical interventions for more equitable outcomes. [ABSTRACT FROM AUTHOR]

Pioglitazone is class of thiazolidinediones that activates peroxisome proliferator‐activated receptors (PPARs) in adipocytes to improve glucose metabolism and insulin sensitivity and has been used as a treatment for type 2 diabetes. However, the underlying mechanisms of associated pioglitazone‐induced effects remain unclear. Our study aimed to investigate endogenous metabolite alterations associated with pioglitazone administration in healthy male subjects using an untargeted metabolomics approach. All subjects received 30 mg of pioglitazone once daily in the assigned sequence and period. Urine samples were collected before pioglitazone administration and for 24 h after 7 days of administration. A total of 1465 compounds were detected and filtered using a coefficient of variance below 30% and 108 metabolites were significantly altered upon pioglitazone administration via multivariate statistical analysis. Fourteen significant metabolites were identified using authentic standards and public libraries. Additionally, pathway analysis revealed that metabolites from purine and beta‐alanine metabolisms were significantly altered after pioglitazone administration. Further analysis of quantification of metabolites from purine metabolism, revealed that the xanthine/hypoxanthine and uric acid/xanthine ratios were significantly decreased at post‐dose. Pioglitazone‐dependent endogenous metabolites and metabolic ratio indicated the potential effect of pioglitazone on the activation of PPAR and fatty acid synthesis. Additional studies involving patients are required to validate these findings. [ABSTRACT FROM AUTHOR]

Purpose: Improving the quality and maintaining the fidelity of large coverage abdominal hyperpolarized (HP) 13C MRI studies with a patch based global–local higher‐order singular value decomposition (GL‐HOVSD) spatiotemporal denoising approach. Methods: Denoising performance was first evaluated using the simulated [1‐13C]pyruvate dynamics at different noise levels to determine optimal kglobal and klocal parameters. The GL‐HOSVD spatiotemporal denoising method with the optimized parameters was then applied to two HP [1‐13C]pyruvate EPI abdominal human cohorts (n = 7 healthy volunteers and n = 8 pancreatic cancer patients). Results: The parameterization of kglobal = 0.2 and klocal = 0.9 denoises abdominal HP data while retaining image fidelity when evaluated by RMSE. The kPX (conversion rate of pyruvate‐to‐metabolite, X = lactate or alanine) difference was shown to be <20% with respect to ground‐truth metabolic conversion rates when there is adequate SNR (SNRAUC > 5) for downstream metabolites. In both human cohorts, there was a greater than nine‐fold gain in peak [1‐13C]pyruvate, [1‐13C]lactate, and [1‐13C]alanine apparent SNRAUC. The improvement in metabolite SNR enabled a more robust quantification of kPL and kPA. After denoising, we observed a 2.1 ± 0.4 and 4.8 ± 2.5‐fold increase in the number of voxels reliably fit across abdominal FOVs for kPL and kPA quantification maps. Conclusion: Spatiotemporal denoising greatly improves visualization of low SNR metabolites particularly [1‐13C]alanine and quantification of [1‐13C]pyruvate metabolism in large FOV HP 13C MRI studies of the human abdomen. [ABSTRACT FROM AUTHOR]

Efficiently creating a concise but comprehensive data set for training machine-learned interatomic potentials (MLIPs) is an under-explored problem. Active learning, which uses biased or unbiased molecular dynamics (MD) to generate candidate pools, aims to address this objective. Existing biased and unbiased MD-simulation methods, however, are prone to miss either rare events or extrapolative regions—areas of the configurational space where unreliable predictions are made. This work demonstrates that MD, when biased by the MLIP's energy uncertainty, simultaneously captures extrapolative regions and rare events, which is crucial for developing uniformly accurate MLIPs. Furthermore, exploiting automatic differentiation, we enhance bias-forces-driven MD with the concept of bias stress. We employ calibrated gradient-based uncertainties to yield MLIPs with similar or, sometimes, better accuracy than ensemble-based methods at a lower computational cost. Finally, we apply uncertainty-biased MD to alanine dipeptide and MIL-53(Al), generating MLIPs that represent both configurational spaces more accurately than models trained with conventional MD. [ABSTRACT FROM AUTHOR]

The preparation of alanine from waste polylactic acid (PLA) is not only an effective way to recycle waste plastics, but also of great significance to develop a green, clean and efficient amino acid production process. In this work, we studied the synthesis of alanine by amination of PLA with ammonia solution over different types of supported bimetallic catalysts without external hydrogen. It was found that the bimetallic catalyst consisting of Ru and a non-precious metal Co supported on TiO2 (Ru–Co/TiO2) was efficient for the reaction. The selectivity of alanine and turnover frequency (TOF) were 65.2% and 1.5 h−1, respectively. The synergistic effect existing between Ru and Co in the catalyst was crucial for the catalytic performance, and the content of precious metal Ru in the catalyst was lower. This was the first attempt to introduce a non-precious metal component into the catalyst for the amination of polylactic acid to alanine through thermocatalysis. [ABSTRACT FROM AUTHOR]

ReAV, the inducible Class-3 L-asparaginase from the nitrogen-fixing symbiotic bacterium Rhizobium etli, is an interesting candidate for optimizing its enzymatic potential for antileukemic applications. Since it has no structural similarity to known enzymes with this activity, it may offer completely new ways of approach. Also, as an unrelated protein, it would evade the immunological response elicited by other asparaginases. The crystal structure of ReAV revealed a uniquely assembled protein homodimer with a highly specific C135/K138/C189 zinc binding site in each subunit. It was also shown before that the Zn2+ cation at low and optimal concentration boosts the ReAV activity and improves substrate specificity, which indicates its role in substrate recognition. However, the detailed catalytic mechanism of ReAV is still unknown. In this work, we have applied site-directed mutagenesis coupled with enzymatic assays and X-ray structural analysis to elucidate the role of the residues in the zinc coordination sphere in catalysis. Almost all of the seven ReAV muteins created in this campaign lost the ability to hydrolyze L-asparagine, confirming our predictions about the significance of the selected residues in substrate hydrolysis. We were able to crystallize five of the ReAV mutants and solve their crystal structures, revealing some intriguing changes in the active site area as a result of the mutations. With alanine substitutions of Cys135 or Cys189, the zinc coordination site fell apart and the mutants were unable to bind the Zn2+ cation. Moreover, the absence of Lys138 induced atomic shifts and conformational changes of the neighboring residues from two active-site Ser-Lys tandems. Ser48 from one of the tandems, which is hypothesized to be the catalytic nucleophile, usually changes its hydration pattern in response to the mutations. Taken together, the results provide many useful clues about the catalytic mechanism of the enzyme, allowing one to cautiously postulate a possible enzymatic scenario. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) has attracted increasing interest as a sustainable plastic because it can be degraded into CO2 and H2O in nature. However, this process is sluggish, and even worse, it is a CO2‐emitting and carbon resource waste process. Therefore, it is highly urgent to develop a novel strategy for recycling post‐consumer PLA to achieve a circular plastic economy. Herein, we report a one‐pot photoreforming route for the efficient and selective amination of PLA waste into value‐added alanine using CoP/CdS catalysts under mild conditions. Results show the alanine production rate can reach up to 2.4 mmol gcat−1 h−1, with a high selectivity (>75 %) and excellent stability. Time‐resolved transient absorption spectra (TAS) reveal that CoP can rapidly extract photogenerated electrons from CdS to accelerate proton reduction, favoring hole‐dominated PLA oxidation to coproduce alanine. This study offers an appealing way for upcycling PLA waste and creates new opportunities for green synthesis of amino acids. [ABSTRACT FROM AUTHOR]

Preservation of fish as diet ingredient is challenging in many tropical regions due to poor socioeconomic conditions and lack of freezing facilities. So, alternative preservation techniques could be viable to address the issue. The present study evaluated the effect of brine salting (15% w/v) prior to drying at different temperatures on the nutrient profiles of tambaqui fish (Colossoma macropomum). Whole fish samples (n = 48; 792 ± 16 g; 8 months old) were grouped into two as brine-salted and non-salted, and treated at seven different drying temperatures of 30, 35, 40, 45, 50, 55 and 60°C for a period of 23 h each. To evaluate the impact of Maillard reaction, reactive lysine was also quantified. Drying temperature had no effect on the evaluated macro- and micro-nutrients of tambaqui fish (P > 0.05) while brining reduced the overall protein concentration by 6% (58.8 to 55.4 g/100 g DM; P = 0.004). Brining significantly reduced many amino acids: taurine by 56% (7.1 to 3.1 g/kg; P < 0.001), methionine 17% (14.7 to 12.1 g/kg; P < 0.001), cysteine 11% (5.1 to 4.4 g/kg, P = 0.016), and reactive lysine 11% (52.0 to 46.4 g/kg; P = 0.004). However, alanine, arginine, and serine were not affected by brining (P > 0.05). Brining also reduced the concentrations of Se by 14% (149 to 128 μg/kg DM; P = 0.020), iodine 38% (604 to 373 μg/kg DM; P = 0.020), K 42% (9.71 to 5.61 g/kg DM; P < 0.001) and Mg 18% (1.32 to 1.10 g/kg DM; P = < 0.001) versus an anticipated vast increase in Na by 744% (2.70 to 22.90 g/kg DM; P < 0.001) and ash 28% (12.4 to 16.0 g/100g DM; P < 0.001) concentration. Neither brining nor drying temperature induced changes in % lysine reactivity and fat content of tambaqui fish (P > 0.05). Agreeably, results of multivariate analysis showed a negative association between brining, Na, and ash on one side of the component and most other nutrients on the other component. In conclusion, drying without brining may better preserve the nutritive value of tambaqui fish. However, as a practical remark to the industry sector, it is recommended that the final product may further evaluated for any pathogen of economic or public health importance. [ABSTRACT FROM AUTHOR]

The natural pesticide phenazine-1-carboxylic acid (PCA) is known to lack phloem mobility, whereas Metalaxyl is a representative phloem systemic fungicide. In order to endow PCA with phloem mobility and also enhance its antifungal activity, thirty-two phenazine-1-carboxylic acid-N-phenylalanine esters conjugates were designed and synthesized by conjugating PCA with the active structure N-acylalanine methyl ester of Metalaxyl. All target compounds were characterized by 1H NMR, 13C NMR and HRMS. The antifungal evaluation results revealed that several target compounds exhibited moderate to potent antifungal activities against Sclerotinia sclerotiorum, Bipolaris sorokiniana, Phytophthora parasitica, Phytophthora citrophthora. In particular, compound F7 displayed excellent antifungal activity against S. sclerotiorum with an EC50 value of 6.57 µg/mL, which was superior to that of Metalaxyl. Phloem mobility study in castor bean system indicated good phloem mobility for the target compounds F1–F16. Particularly, compound F2 exhibited excellent phloem mobility; the content of compound F2 in the phloem sap of castor bean was 19.12 μmol/L, which was six times higher than Metalaxyl (3.56 μmol/L). The phloem mobility tests under different pH culture solutions verified the phloem translocation of compounds related to the "ion trap" effect. The distribution of the compound F2 in tobacco plants further suggested its ambimobility in the phloem, exhibiting directional accumulation towards the apical growth point and the root. These results provide valuable insights for developing phloem mobility fungicides mediated by exogenous compounds. [ABSTRACT FROM AUTHOR]

Simple Summary: Diarrhea is a major cause of mortality in young yaks. This study investigates its impact on the gut microbiota of these animals. The results show a decrease in microbial diversity and an increase in harmful bacteria like Eysipelatoclostridium, Parabacteroides, and Escherichia-Shigella during diarrhea. A metabolic pathway analysis reveals heightened activity in the associated pathways. These outcomes indicate that dysbiosis in the gut microbiota may be a key factor driving diarrhea outbreaks in yaks in the Qinghai-Tibet plateau. Diarrhea-induced mortality among juvenile yaks is highly prevalent in the pastoral areas of the Qinghai-Tibet plateau. Although numerous diseases have been linked to the gut microbial community, little is known about how diarrhea affects the gut microbiota in yaks. In this work, we investigated and compared changes in the gut microbiota of juvenile yaks with diarrhea. The results demonstrated a considerable drop in the alpha diversity of the gut microbiota in diarrheic yaks, accompanied by Eysipelatoclostridium, Parabacteroides, and Escherichia-Shigella, which significantly increased during diarrhea. Furthermore, a PICRust analysis verified the elevation of the gut–microbial metabolic pathways in diarrhea groups, including glycine, serine, and threonine metabolism, alanine, aspartate, oxidative phosphorylation, glutamate metabolism, antibiotic biosynthesis, and secondary metabolite biosynthesis. Taken together, our study showed that the harmful bacteria increased, and beneficial bacteria decreased significantly in the gut microbiota of yaks with diarrhea. Moreover, these results also indicated that the dysbiosis of the gut microbiota may be a significant driving factor of diarrhea in yaks. [ABSTRACT FROM AUTHOR]

Aims: The role of liver steatosis and increased liver enzymes (ALT) in increasing incident type 2 diabetes mellitus (T2DM) is debated, because of their differential effects on different ethnicities and populations. The aim of this study was to evaluate the role of elevated ALT in the development of T2DM in non-diabetic obese subjects receiving routine medical treatment. Methods: A total of 1005 subjects [296 men and 709 women, aged 45.7 ± 13.12 years, body mass index (BMI) 39.5 ± 4.86 kg/m2] were followed for a mean period of 14.3 ± 4.44 years. Subjects were evaluated for several metabolic variables, including the triglyceride-glucose index and the presence of metabolic syndrome (IDF 2005 definition), and were subdivided into ALT quartiles. Results: T2DM developed in 136 subjects, and the difference was significant between the first and the fourth ALT quartile (p = 0.048). Both at univariate analysis and at stepwise regression, ALT quartiles were associated with incident T2DM. Traditional risk factors for T2DM coexisted, with a somehow greater predictive value, such as triglyceride-glucose index, age, arterial hypertension, LDL-cholesterol, and metabolic syndrome. Conclusions: These data suggest an association between elevated ALT levels and the risk of incident T2DM in obesity. [ABSTRACT FROM AUTHOR]

Background: Non-small cell lung cancer (NSCLC) is a type of lung cancer that occurs in the cells of the respiratory tract, and its development is influenced by the regulation of circular RNAs (circRNAs). However, the role of circRNA carboxypeptidase A4 (circCPA4) in the progression of NSCLC and the underlying mechanism remain relatively clear. Methods: The study utilized both real-time quantitative polymerase chain reaction (RT-qPCR) and western blot techniques to evaluate the levels of circCPA4, microRNA-145-5p (miR-145-5p), alanine, serine, or cysteine-preferring transporter 2 (ASCT2). To assess cell proliferation, cell counting kit-8 (CCK8) and 5-ethynyl-20-deoxyuridine (EdU) assays were performed. Apoptosis was determined using flow cytometry, while cell migration and invasive capacity were evaluated through transwell and wound-healing assays. Intracellular levels of glutamine, glutamate, and α-KG were measured using specific kits. The relationship between miR-145-5p and circCPA4 or ASCT2 was confirmed using dual-luciferase reporter assay and RNA immunoprecipitation assay. Results: CircCPA4 and ASCT2 RNA levels were elevated, while miR-145-5p was downregulated in both NSCLC tissues and cells. Depletion of circCPA4 significantly inhibited NSCLC cell proliferation, migration, invasion, and intracellular levels of glutamine, glutamate, and α-KG, and promoted apoptosis. Moreover, circCPA4 knockdown delayed tumor growth in vivo. Furthermore, circCPA4 was found to bind to miR-145-5p, thereby regulating the progression of NSCLC in vitro. ASCT2 was also identified as a downstream target of miR-145-5p, and its upregulation rescued the effects of miR-145-5p overexpression on NSCLC cell processes. Conclusion: CircCPA4 knockdown inhibited tumor property of NSCLC cells by modulating the miR-145-5p/ASCT2 axis. [ABSTRACT FROM AUTHOR]

This study is intended to analyze and compare halophilic RuBisCo-like proteins (RLP) with non-halophilic homologs using computational analysis approaches. The data used were protein sequences from NCBI and protein sequences from clonned and expressed RuBisCo-like proteins Chromohalobacter salexigens BKL 5 from our previous study. The analysis was in the form of Principal Component Analysis (PCA) and Partial Least Square (PLS). The tools used were Origin Lab Full Version 2019 and Metaboanalyst 5.0. The parameters tested were isoelectric point (pI), negative charge (acidic amino acids), aliphatic index, and GRAVY index using the ProtParam tool from Expasy. Calculations analysis showed that the amino acid residues in halophilic RuBisCo-like proteins that differ significantly from their homologs were glutamic acid and alanine, while the variables that could be observed as differentiating were negative charge and aliphatic index. Analysis shows that some parameters obtained from the program can be used as discriminants to differentiate halophilic and non-halophilic RuBisCo-like proteins. [ABSTRACT FROM AUTHOR]

We found that urine tenofovir (TFV) levels >1500 ng/mL strongly predict virologic suppression among people with human immunodeficiency virus taking tenofovir alafenamide (odds ratio, 5.66; 95% confidence interval, 1.59-20.14; P = .007). This suggests an existing point-of-care assay developed for tenofovir disoproxil fumarate will support adherence monitoring for patients on all TFV-based antiretrovirals.

Despite unprecedented efforts, our therapeutic arsenal against SARS-CoV-2 remains limited. The conserved macrodomain 1 (Mac1) in NSP3 is an enzyme exhibiting ADP-ribosylhydrolase activity and a possible drug target. To determine the role of Mac1 catalytic activity in viral replication, we generated recombinant viruses and replicons encoding a catalytically inactive NSP3 Mac1 domain by mutating a critical asparagine in the active site. While substitution to alanine (N40A) reduced catalytic activity by ~10-fold, mutations to aspartic acid (N40D) reduced activity by ~100-fold relative to wild-type. Importantly, the N40A mutation rendered Mac1 unstable in vitro and lowered expression levels in bacterial and mammalian cells. When incorporated into SARS-CoV-2 molecular clones, the N40D mutant only modestly affected viral fitness in immortalized cell lines, but reduced viral replication in human airway organoids by 10-fold. In mice, the N40D mutant replicated at >1000-fold lower levels compared to the wild-type virus while inducing a robust interferon response; all animals infected with the mutant virus survived infection. Our data validate the critical role of SARS-CoV-2 NSP3 Mac1 catalytic activity in viral replication and as a promising therapeutic target to develop antivirals.

To obtain cobalt target activity data after a cycle of irradiation in a pressurized water reactor, the cobalt target dose distribution was measured underwater using alanine dosimeters. The effects of cobalt target structure, water medium, measurement device, operation, and environment were corrected using Monte Carlo calculations. The feasibility of the method and device was confirmed through both experimental and Monte Carlo comparison. The underwater measurement data of cobalt target activity matches the theoretical calculated values, with an uncertainty of 6.5%.

Beta-alanine, caffeine, and nitrate are dietary supplements generally recognized by the sport and exercise science community as evidence-based ergogenic performance aids. Evidence supporting the efficacy of these supplements, however, is greatly skewed due to research being conducted primarily in men. The physiological differences between men and women, most notably in sex hormones and menstrual cycle fluctuations, make generalizing male data to the female athlete inappropriate, and potentially harmful to women. This narrative review outlines the studies conducted in women regarding the efficacy of beta-alanine, caffeine, and nitrate supplementation for performance enhancement. Only nine studies on beta-alanine, 15 on caffeine, and 10 on nitrate in healthy women under the age of 40 years conducted in normoxia conditions were identified as relevant to this research question. Evidence suggests that beta-alanine may lower the rate of perceived exertion and extend training bouts in women, leading to greater functional adaptations. Studies of caffeine in women suggest the physiological responder status and caffeine habituation may contribute to caffeine's efficacy, with a potential plateau in the dose–response relationship of performance enhancement. Nitrate appears to vary in influence based on activity type and primary muscle group examined. However, the results summarized in the limited literature for each of these three supplements provide no consensus on dosage, timing, or efficacy for women. Furthermore, the literature lacks considerations for hormonal status and its role in metabolism. This gap in sex-based knowledge necessitates further research on these ergogenic supplements in women with greater considerations for the effects of hormonal status. [ABSTRACT FROM AUTHOR]

SARS coronavirus 2 (SARS-CoV-2) has caused an ongoing global pandemic with significant mortality and morbidity. At this time, the only FDA-approved therapeutic for COVID-19 is remdesivir, a broad-spectrum antiviral nucleoside analog. Efficacy is only moderate, and improved treatment strategies are urgently needed. To accomplish this goal, we devised a strategy to identify compounds that act synergistically with remdesivir in preventing SARS-CoV-2 replication. We conducted combinatorial high-throughput screening in the presence of submaximal remdesivir concentrations, using a human lung epithelial cell line infected with a clinical isolate of SARS-CoV-2. This identified 20 approved drugs that act synergistically with remdesivir, many with favorable pharmacokinetic and safety profiles. Strongest effects were observed with established antivirals, Hepatitis C virus nonstructural protein 5A (HCV NS5A) inhibitors velpatasvir and elbasvir. Combination with their partner drugs sofosbuvir and grazoprevir further increased efficacy, increasing remdesivir's apparent potency > 25-fold. We report that HCV NS5A inhibitors act on the SARS-CoV-2 exonuclease proofreader, providing a possible explanation for the synergy observed with nucleoside analog remdesivir. FDA-approved Hepatitis C therapeutics Epclusa® (velpatasvir/sofosbuvir) and Zepatier® (elbasvir/grazoprevir) could be further optimized to achieve potency and pharmacokinetic properties that support clinical evaluation in combination with remdesivir.

Francisella tularensis, a Tier 1 select agent of bioterrorism, contains a type VI secretion system (T6SS) encoded within the Francisella pathogenicity island (FPI), which is critical for its pathogenesis. Among the 18 proteins encoded by FPI is IglD, which is essential to Francisella's intracellular growth and virulence, but neither its location within T6SS nor its functional role has been established. Here, we present the cryoEM structure of IglD from Francisella novicida and show that the Francisella IglD forms a homotrimer that is structurally homologous to the T6SS baseplate protein TssK in Escherichia coli. Each IglD monomer consists of an N-terminal β-sandwich domain, a 4-helix bundle domain, and a flexible C-terminal domain. While the overall folds of IglD and TssK are similar, the two structures differ in three aspects: the relative orientation between their β-sandwich and the 4-helix bundle domains; two insertion loops present in TssK's β-sandwich domain; and, consequently, a lack of subunit-subunit interaction between insertion loops in the IglD trimer. Phylogenetic analysis indicates that IglD is genetically remote from the TssK orthologs in other T6SSs. While the other components of the Francisella baseplate are unknown, we conducted pulldown assays showing IglJ interacts with IglD and IglH, pointing to a model wherein IglD, IglH, and IglJ form the baseplate of the Francisella T6SS. Alanine substitution mutagenesis further established that IglD's hydrophobic pocket in the N-terminal β-sandwich domain interacts with two loops of IglJ, reminiscent of the TssK-TssG interaction. These results form a framework for understanding the hitherto unexplored Francisella T6SS baseplate. IMPORTANCE Francisella tularensis is a facultatively intracellular Gram-negative bacterium that causes the serious and potentially fatal zoonotic illness, tularemia. Because of its extraordinarily high infectivity and mortality to humans, especially when inhaled, F. tularensis is considered a potential bioterrorism agent and is classified as a Tier 1 select agent. The type VI secretion system (T6SS) encoded within the Francisella pathogenicity island (FPI) is critical to its pathogenesis, but its baseplate components are largely unknown. Here, we report the cryoEM structure of IglD from Francisella novicida and demonstrate its role as a component of the baseplate complex of the Francisella T6SS. We further show that IglD interacts with IglJ and IglH, and propose a model in which these proteins interact to form the Francisella T6SS baseplate. Elucidation of the structure and composition of the Francisella baseplate should facilitate the design of strategies to prevent and treat infections caused by F. tularensis.

PurposeWe constructed a 13C/31P surface coil at 3 T for studying cancer metabolism and bioenergetics. In a single scan session, hyperpolarized 13C-pyruvate MRS and 31P MRS was carried out for a healthy rat brain.MethodsAll experiments were carried out at 3 Tesla. The multinuclear surface coil was designed as two coplanar loops each tuned to either the 13C or 31P operating frequency with an LCC trap on the 13C loop. A commercial volume proton coil was used for anatomical localization and B0 shimming. Single tuned coils operating at either the 13C or 31P frequency were built to evaluate the relative performance of the multinuclear coil. Coil performance metrics consisted of measuring Q factor ratio, calculating system input power using a single-pulse acquisition, and acquiring SNR and flip angle maps using 2D CSI sequences. To observe in vivo spectra, a bolus of hyperpolarized [1-13C] pyruvate was administered via tail vein. In vivo13C and endogenous 31P spectra were obtained in a single scan session using 1D slice selective acquisitions.ResultsWhen compared with single tuned surface coils, the multinuclear coil performance showed a decrease in Q factor ratio, SNR, and transmit efficiency. Flip angle maps showed adequate flip angles within the phantom when the transmit voltage was set using an external phantom. Results show good detection of 13C labeled lactate, alanine, and bicarbonate in addition to ATP from 31P MRS.ConclusionsThe coil enables obtaining complementary information within a scan session, thus reducing the number of trials and minimizing biological variability for studies of metabolism and bioenergetics.

Background: ZhuRiHeng Drop Pill (ZRH) is a traditional Mongolian medicinal preparation. Despite its long history of use for the treatment of coronary heart disease, there have been few toxicological studies of the safety profile of ZRH. Purpose: In order to comprehensively elucidate the underlying mechanisms behind the observed toxicity of ZRH on rat livers in the 180-day repeated oral toxicity study, we conducted a comprehensive analysis by integrating transcriptomic and metabolomic data. Methods: High-resolution mass spectrometry was conducted to evaluate the constituents of ZRH. For the acute oral toxicity study, mice were administered a dose of 32 g/(kg·d) of ZRH, while rats were instead orally administered 0.934, 1.868, or 3.736 g/(kg·d) of ZRH over a 180-day period in a 180-day repeated oral toxicity study. Conventional index and organ weights/histology were then monitored to detect any potential ZRH treatment-related toxicity. To identify key genes and metabolites involved in ZRH toxicological processes, we performed transcriptomic and metabolomic analyses of liver tissue upon ZRH treatment using RNA-seq techniques, qPCR and liquid chromatography-mass spectrometry analyses. Results: A total of 60 compounds in ZRH were identified and speculated in positive and negative ion modes. Mice in the acute toxicity study exhibited no signs of ZRH-related toxicity. In a protracted oral toxicity investigation spanning 180 days, discernible elevations in liver ratios were noted in both male and female rats across all three dose cohorts, relative to the control group (p < 0.05 or p < 0.01). Upon subjecting to ZRH treatment, our transcriptomic and qPCR analyses unveiled notable upregulation of crucial genes, exemplified by Abcb1b and Cyp2b2, known for theirs involvement in liver drug transport and metabolism function. Furthermore, our untargeted metabolomic analysis provided supplementary insights, revealing significant regulation in pyrimidine metabolism, as well as alanine, aspartate, and glutamate metabolism pathways. Conclusion: Our study unveils a panoramic understanding of the temporal, dosage-specific, and gene dimensions surrounding the metabolic and transcriptional shifts induced by ZRH exposure. As we peer into the future, recommendations emerge for further exploration, encompassing aspects such as time dynamics, dosage considerations, and gene-centric avenues to enhance therapeutic efficacy. [ABSTRACT FROM AUTHOR]

Tautomerization paths of β‐alanine with explicit inclusion of water molecules, (H2O)n, were investigated by DFT calculations, wB97X‐D/6‐311+G(d,p) SCRF=PCM. Structures of zwitterions of the alanine of trans (t−) and gauche (g−) conformations with seven water molecules (n=7) were examined. On the basis of those geometries, elementary processes of the tautomerization were investigated. For the t‐conformer of β‐alanine, reaction models of n=8, 10, 14, 18 and 24 were scrutinized. While reaction processes are slightly modified with different number of water molecules, n=18 and 24 models afforded three elementary reactions, t‐alanine with cis‐COOH→t‐ion pair→t‐alanine with trans‐COOH→t‐zwitterion. The (H2O)4 hydrogen‐bonded chain participates in the reactions. For the g‐conformer, models of n=7, 10, 14 and 18 were investigated, and the tautomerization was found to take place concertedly via (H2O)2. [ABSTRACT FROM AUTHOR]

Ribosomes stall on truncated or otherwise damaged mRNAs. Bacteria rely on ribosome rescue mechanisms to replenish the pool of ribosomes available for translation. Trans-translation, the main ribosome-rescue pathway, uses a circular hybrid transfer-messenger RNA (tmRNA) to restart translation and label the resulting peptide for degradation. Previous studies have visualized how tmRNA and its helper protein SmpB interact with the stalled ribosome to establish a new open reading frame. As tmRNA presents the first alanine codon via a non-canonical mRNA path in the ribosome, the incoming alanyl-tRNA must rearrange the tmRNA molecule to read the codon. Here, we describe cryo-EM analyses of an endogenous Escherichia coli ribosome-tmRNA complex with tRNAAla accommodated in the A site. The flexible adenosine-rich tmRNA linker, which connects the mRNA-like domain with the codon, is stabilized by the minor groove of the canonically positioned anticodon stem of tRNAAla. This ribosome complex can also accommodate a tRNA near the E (exit) site, bringing insights into the translocation and dissociation of the tRNA that decoded the defective mRNA prior to tmRNA binding. Together, these structures uncover a key step of ribosome rescue, in which the ribosome starts translating the tmRNA reading frame. [ABSTRACT FROM AUTHOR]

Amino acids and their complexes are organic or semiorganic materials that have attracted considerable attention because they can be easily used in optical storage devices. DL-alanine is one of the rare amino acids that crystallizes in anoncentrosymmetric group. This article demonstrates how DL-alanine potassium dichromate (DAPC) single crystals have shown sufficient growth. DAPC crystals were analyzed by single crystal X-ray diffraction and powder X-ray diffraction. Using thermogravimetric analysis/differential thermal analysis (TGA/DTA) and differential scanning calorimetry, this work also examined the melting point, thermal stability, decomposition point, and other thermal parameters of the DAPC crystals. Results show that the decomposition point of DAPC is 397 °C, which is analogous to that of TG/DTA. The dielectric constant, dissipation, and AC conductivity were also measured, and the results were analyzed to understand various features of the current operating model. The activation energy of the DAPC single crystal is 0.074 eV. [ABSTRACT FROM AUTHOR]

Aim: We aimed to evaluate the metabolite ratios that could predict the clinical incidence or remission of type 2 diabetes mellitus (T2D). Methods: The Cox proportional hazards regression model was used to assess 1813 individuals without T2D to test the predictive value of metabolite ratios for T2D incidence and 451 newly diagnosed T2D for remission. The receiver operating characteristic curve analysis was performed to determine the best cut‐off values for the metabolite ratios. Survival analyses were performed to compare the four subgroups defined by baseline metabolite ratios and clinical status of obesity. Results: The alanine/glycine was the most significant marker for T2D incidence (hazard ratio per SD: 1.24; p <.001). On the other hand, metabolite hydroxy sphingomyelin C22:2 was most specific for T2D remission (hazard ratio per SD: 1.32; p =.029). Survival analysis of T2D incidence among the subgroups defined by the combination of alanine/glycine and obesity showed the group with a high alanine/glycine and obesity had the highest risk of T2D incidence (p <.001). The alanine/glycine as a T2D risk marker was also validated in the independent external data. Conclusions: The combination of obesity and the alanine/glycine ratio can be used to evaluate the diabetes risk. [ABSTRACT FROM AUTHOR]

The article discusses a 15-year-old female with Graves' disease who developed acute liver injury secondary to autoimmune hepatitis (AIH) after initiating methimazole treatment, highlighting diagnostic and therapeutic challenges in managing coexisting autoimmune conditions. Topics include diagnostic dilemma posed by elevated transaminases in Graves' disease patients, the importance of comprehensive hepatitis workup, and the therapeutic approach to managing AIH alongside hyperthyroidism.

The function of exogenous alanine (Ala) in regulating biomass accumulation, lipid production, photosynthesis, and respiration in Chlorella pyrenoidosa was studied. Result shows that the supplementation of Ala increased C. pyrenoidosa biomass and lipid production in an 8-d batch culture. The concentration of 10 mmol/L of Ala was optimum and increased the microalgal cell biomass and lipid content by 39.3% and 21.4%, respectively, compared with that in the control (0-mmol/L Ala). Ala supplementation reduced photosynthetic activity while boosting respiratory activity and pyruvate levels, indicating that C. pyrenoidosa used exogenous Ala for biomass accumulation through the respiratory metabolic process. The accelerated respiratory metabolism due to Ala supplementation elevated the substrate pool and improved the lipogenic gene expression, promoting lipid production at last. This study provided a novel method for increasing biomass accumulation and lipid production and elucidated the role of Ala in regulating lipid production. [ABSTRACT FROM AUTHOR]

Abnormal trinucleotide repeat expansions alter protein conformation causing malfunction and contribute to a significant number of incurable human diseases. Scarce structural insights available on disease-related homorepeat expansions hinder the design of effective therapeutics. Here, we present the dynamic structure of human PHOX2B C-terminal fragment, which contains the longest polyalanine segment known in mammals. The major α-helical conformation of the polyalanine tract is solely extended by polyalanine expansions in PHOX2B, which are responsible for most congenital central hypoventilation syndrome cases. However, polyalanine expansions in PHOX2B additionally promote nascent homorepeat conformations that trigger length-dependent phase transitions into solid condensates that capture wild-type PHOX2B. Remarkably, HSP70 and HSP90 chaperones specifically seize PHOX2B alternative conformations preventing phase transitions. The precise observation of emerging polymorphs in expanded PHOX2B postulates unbalanced phase transitions as distinct pathophysiological mechanisms in homorepeat expansion diseases, paving the way towards the search of therapeutics modulating biomolecular condensates in central hypoventilation syndrome. Here, the authors show that pathogenic mutations in the polyalanine expansions of PHOX2B promote nascent structural conformations that trigger irreversible phase transitions that arrest wild-type PHOX2B, disrupting function. [ABSTRACT FROM AUTHOR]

Dehydroabietic acid is a natural product in the class of rosins. Here we report the design, synthesis and characterization of copolymers containing dehydroabietate side‐chain pendents, derived from homologated dehydroabietic ethyl methacrylate and tert‐butoxy carbonyl (Boc) l‐alanine methacryloyloxyethyl ester with varying comonomer proportions by reversible addition fragmentation chain transfer polymerization. The cleavage of Boc groups from the copolymers resulted in water‐soluble copolymers with cationic surface charge. Since proper hydrophobic−hydrophilic balance in a single polymer chain is maintained, the copolymers self‐assembled in aqueous media with a critical aggregation concentration of 2.8–3.0 mg L−1, confirmed by fluorescence spectroscopy. 1H NMR spectroscopy, dynamic light scattering, SEM and AFM were used to further investigate the aqueous solution self‐assembly of random copolymers. The collective findings from 1H NMR, dynamic light scattering, SEM and AFM clearly revealed the existence of micellar particles in water with alanine units on the surface of the nanoaggregates and homologated dehydroabietate pendents along with the hydrophobic main‐chain backbone in the core. In addition, to get a clear insight into the nanoaggregates' potential for drug encapsulation in aqueous medium, Nile Red was incorporated as a model hydrophobic dye. © 2023 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

In this work we carried out an in silico analysis to understand the interaction between InvF-SicA and RNAP in the bacterium Salmonella Typhimurium strain LT2. Structural analysis of InvF allowed the identification of three possible potential cavities for interaction with SicA. This interaction could occur with the structural motif known as tetratricopeptide repeat (TPR) 1 and 2 in the two cavities located in the interface of the InvF and a-CTD of RNAP. Indeed, molecular dynamics simulations showed that SicA stabilizes the Helix-turn-Helix DNA-binding motifs, i. e., maintaining their proper conformation, mainly in the DNA Binding Domain (DBD). Finally, to evaluate the role of amino acids that contribute to protein-protein affinity, an alanine scanning mutagenesis approach, indicated that R177 and R181, located in the DBD motif, caused the greatest changes in binding affinity with a-CTD, suggesting a central role in the stabilization of the complex. However, it seems that the N-terminal region also plays a key role in the protein-protein interaction, especially the amino acid R40, since we observed conformational flexibility in this region allowing it to interact with interface residues. We consider that this analysis opens the possibility to validate experimentally the amino acids involved in protein-protein interactions and explore other regulatory complexes where chaperones are involved. [ABSTRACT FROM AUTHOR]

Background and Aim: The recent review of research conducted in the field of air pollution and sports shows that there is a serious impact of air pollutants as well as the new pollutant of dust particles, and it is imperative to pay attention to this issue. This research aims to investigate the effect of regular exercise on lung function and amino acid arginine-alanine in traffic police of the provinces affected by dust particles in Iran. Methods: Forty traffic police officers (age: 23.62 ± 6.4 years; body mass index: 27.44 ± 4.7 kg/m2) were voluntarily selected from the centers of Khuzestan, Ilam, and Kermanshah provinces and randomly assigned to two control and regular physical activity groups. Regular physical activity included: 30 sessions, circuit training three times a week including hanging from the chin up (20 seconds), jumping over obstacles (knee height) at a distance of one meter for a total of 540 cm, Sit-ups (30 seconds), chest press (70% 1RM-8 repetitions), leg press (70% 1RM -8 repetitions), back extension (15 repetitions), calf raise (70% 1RM -8 repetitions), zigzag jump (20 repetitions), six to ten reputation Illinois Agility Test with a 30-second rest interval. Before the study, 48 hours before the occurrence of dust particles, and after the study fat percentage, amino acids, WBC, and FEV1/FVC were measured. To examine the research data, we used the mean and standard deviation as well as repeated analysis of variance (P ≥0.05). Results: It was found that time (pre-test-May 12, 2023) had a significant effect on amino acids argininealanine, maximum oxygen consumption, body fat percentage, and FEV1/FVC in the training group (P <0.05). In the control group, there was no significant difference in the amino acid arginine-alanine, maximum oxygen consumption, body fat percentage, or FEV1/FVC (P >0.05). However, the effect of time was present in the control group only for white blood cells (P <0.001). In terms of body fat percentage, there was a significant difference between the control and exercise groups (P = 0.01), as well as maximum oxygen consumption (P = 0.01). Conclusion: This study has demonstrated that regular exercise training can improve lung function, aerobic fitness, body fat percentage, and levels of amino acids involved in the immune system, as well as increase muscle mass and anti-inflammatory effects that reduce dust particle damage in those exposed to dust particles. [ABSTRACT FROM AUTHOR]

Extreme weather conditions lead to significant imbalances in crop productivity, which in turn affect food security. Flooding events cause serious problems for many crop species such as wheat. Although metabolic readjustments under flooding are important for plant regeneration, underlying processes remain poorly understood. Here, we investigated the systemic response of wheat to waterlogging using metabolomics and transcriptomics. A 12 d exposure to excess water triggered nutritional imbalances and disruption of metabolite synthesis and translocation, reflected by reductions in plant biomass and growth performance. Metabolic and transcriptomic profiling in roots, xylem sap, and leaves indicated anaerobic fermentation processes as a local response in roots. Differentially expressed genes and ontological categories revealed that carbohydrate metabolism plays an important role in the systemic response. Analysis of the composition of xylem exudates revealed decreased root-to-shoot translocation of nutrients, hormones, and amino acids. Interestingly, among all metabolites measured in xylem exudates, alanine was the most abundant. Immersion of excised leaves derived from waterlogged plants in alanine solution led to increased leaf glucose concentration. Our results suggest an important role of alanine not only as an amino-nitrogen donor but also as a vehicle for carbon skeletons to produce glucose de novo and meet the energy demand during waterlogging. [ABSTRACT FROM AUTHOR]

Diabetes is recognized as a risk factor for cognitive decline, but the underlying mechanisms remain elusive. We aimed to identify the metabolic pathways altered in diabetes-associated cognitive decline (DACD) using untargeted metabolomics. We conducted liquid chromatography–mass spectrometry-based untargeted metabolomics to profile serum metabolite levels in 100 patients with type 2 diabetes (T2D) (54 without and 46 with DACD). Multivariate statistical tools were used to identify the differentially expressed metabolites (DEMs), and enrichment and pathways analyses were used to identify the signaling pathways associated with the DEMs. The receiver operating characteristic (ROC) analysis was employed to assess the diagnostic accuracy of a set of metabolites. We identified twenty DEMs, seven up- and thirteen downregulated in the DACD vs. DM group. Chemometric analysis revealed distinct clustering between the two groups. Metabolite set enrichment analysis found significant enrichment in various metabolite sets, including galactose metabolism, arginine and unsaturated fatty acid biosynthesis, citrate cycle, fructose and mannose, alanine, aspartate, and glutamate metabolism. Pathway analysis identified six significantly altered pathways, including arginine and unsaturated fatty acid biosynthesis, and the metabolism of the citrate cycle, alanine, aspartate, glutamate, a-linolenic acid, and glycerophospholipids. Classifier models with AUC-ROC > 90% were developed using individual metabolites or a combination of individual metabolites and metabolite ratios. Our study provides evidence of perturbations in multiple metabolic pathways in patients with DACD. The distinct DEMs identified in this study hold promise as diagnostic biomarkers for DACD patients. [ABSTRACT FROM AUTHOR]

To explore the genetic diversity and metabolic characteristics among different locations of wild Rhodiola sachalinensis A.Boriss., we collected specimens from two sites (DHL: 128°23′06″ N, 44°26′31″ E; FHS: 127°59′26″ N, 44°7′22″ E) and measured various biological traits, such as leaf length, leaf width, and plant height. We conducted metabolic analyses to investigate variations among different plant parts. Our study revealed that while the various plant parts of wild R. sachalinensis A.Boriss. from these two locations showed overall numerical similarities, they exhibited relatively high coefficients of variation in traits such as leaf length, leaf width, plant height, and stem thickness. Furthermore, utilizing gas chromatography–mass spectrometry (GS-MS), we detected significant differences in primary metabolites among different plant parts from both locations. Using orthogonal partial least squares discriminant analysis (OPLS-DA), we identified 42 and 34 different metabolites in the roots, stems, and leaves of plants from the DHL site and 62 and 50 different metabolites in the roots, stems, and leaves of plants from the FHS site. Metabolic heatmaps suggested that sugar metabolism was more active in the roots compared to other plant parts. Through KEGG pathway analysis, we determined that the primary metabolic differences were concentrated in the citric acid cycle (TCA cycle) and amino acid metabolism, including pathways related to glycine, serine, and threonine metabolism, as well as alanine, aspartate, and glutamate metabolism. These findings indicate that wild R. sachalinensis A.Boriss. plants from different locations not only exhibit significant variations in biological traits but also demonstrate notable distinctions in the distribution of primary metabolites among different plant parts. [ABSTRACT FROM AUTHOR]

Soccer is a sport practiced all over the world and whose practice begins in young athletes. Currently, the consumption of nutritional supplements is essential to achieve the maximum performance of players. The aim of this study was to describe the consumption of sports supplements (CSS) by elite soccer players and its association with their competitive level, playing position, and sex. A comparative descriptive and non-experimental study was performed during the 2021–2022 competitive season. A total of 70 elite players completed one online questionnaire about their CSS. We found that sports drinks (55.7%), sports bars (50.0%), whey protein (48.6%), caffeine (47.1%), and creatine (60.0%) were the most consumed supplements by the total sample. Relative to the categories, the CSS was higher in the senior teams for both men and women. Regarding playing positions, caffeine was more consumed by midfielders and forwards (p = 0.013). Finally, in relation to sex, significant differences were found in the consumption of sports confectionery (p = 0.036), whey protein (p = 0.002), β-alanine (p = 0.013), and melatonin (p = 0.016). Soccer club SS questionnaires gather data to understand patterns, assess effectiveness and risks, and aid research. In conclusion, differences were found in the CSS according to competitive level, sex, and playing position. [ABSTRACT FROM AUTHOR]

Recent clinical data have identified infant patients with lethal ITPA deficiencies. ITPA is known to modulate ITP concentrations in cells and has a critical function in neural development which is not understood. Polymorphism of the ITPA gene affects outcomes for both ribavirin and thiopurine based therapies and nearly one third of the human population is thought to harbor ITPA polymorphism. In a previous site-directed mutagenesis alanine screen of the ITPA substrate selectivity pocket, we identified the ITPA mutant, E22A, as a gain-of function mutant with enhanced ITP hydrolysis activity. Here we report a rational enzyme engineering experiment to investigate the biochemical properties of position 22 ITPA mutants and find that the E22D ITPA has two- and four-fold improved substrate selectivity for ITP over the canonical purine triphosphates ATP and GTP, respectively, while maintaining biological activity. The novel E22D ITPA should be considered as a platform for further development of ITPA therapies. [ABSTRACT FROM AUTHOR]

Background: Remdesivir is an antiviral approved by the US Food and Drug Administration (FDA) for treatment of coronavirus disease 2019 (COVID-19), and aminotransferase elevation is commonly reported. Thresholds to be considered for discontinuation due to alanine aminotransferase (ALT) elevation differ between the FDA and European Medicines Agency (EMA). The primary objective was to describe aminotransferase thresholds being used in real-world practice for discontinuation of remdesivir in patients with COVID-19, and compare them with labeled recommendations. Methods: This study used a descriptive design based on an ongoing national registry of adverse events, the FDA ACMT COVID-19 ToxIC (FACT) pharmacovigilance project, with 17 participating health systems in the USA. Cases were identified retrospectively for an 18-month period (23 November 2020–18 May 2022). Classification of discontinuation as premature and due to aminotransferases was based on chart documentation by the treating team. Results: Of 1026 cases in the FACT registry, 116 cases were included with supplemental data forms completed for aminotransferase elevation with remdesivir, defined a priori for inclusion as ALT doubling or increasing by ≥ 50 U/L. ALT was elevated prior to remdesivir in 47% and increased above baseline during dosing by a median of 92 U/L [interquartile range (IQR) 51–164, max 8350]. Remdesivir was discontinued early in 37 (31.9%) patients due to elevated aminotransferases. The ALT threshold for premature discontinuation was median 200 U/L (IQR 145–396, range 92–5743). Among patients with premature discontinuation of remdesivir for aminotransferase elevation, only 21.6% met FDA criteria to consider discontinuation, and 40.5% met prior EMA criteria to consider discontinuation. Conclusion: In this descriptive study of real-world practice in the USA, clinicians are overall making more conservative treatment decisions than are recommended for consideration in approved drug labeling of discontinuation, with wide variation in the aminotransferase thresholds being used. [ABSTRACT FROM AUTHOR]

The primary objective of this research was to develop efficient solid catalysts that can directly convert the lactic acid (LA) obtained from lignocellulosic biomass into alanine (AL) through a reductive amination process. To achieve this, various catalysts based on ruthenium were synthesized using different carriers such as multi-walled carbon nanotubes (MWCNTs), beta-zeolite, and magnetic nanoparticles (MNPs). Among these catalysts, Ru/MNP demonstrated a remarkable yield of 74.0% for alanine at a temperature of 200 °C. This yield was found to be superior not only to the Ru/CNT (55.7%) and Ru/BEA (6.6%) catalysts but also to most of the previously reported catalysts. The characterization of the catalysts and their catalytic results revealed that metallic ruthenium nanoparticles, which were highly dispersed on the external surface of the magnetic carrier, significantly enhanced the catalyst's ability for dehydrogenation. Additionally, the -NH2 basic sites on the catalyst further facilitated the formation of alanine by promoting the adsorption of acidic reactants. Furthermore, the catalyst could be easily separated using an external magnetic field and exhibited the potential for multiple reuses without any significant loss in its catalytic performance. These practical advantages further enhance its appeal for applications in the reductive amination of lactic acid to alanine. [ABSTRACT FROM AUTHOR]

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This study aims at proof of concept that constant monitoring of the concentrations of metabolites in three individuals' sweat over time can differentiate one from another at any given time, providing investigators and analysts with increased ability and means to individualize this bountiful biological sample. A technique was developed to collect and extract authentic sweat samples from three female volunteers for the analysis of lactate, urea, and L -alanine levels. These samples were collected 21 times over a 40-day period and quantified using a series of bioaffinity-based enzymatic assays with UV-vis spectrophotometric detection. Sweat samples were simultaneously dried, derivatized, and analyzed by a GC-MS technique for comparison. Both UV-vis and GC-MS analysis methods provided a statistically significant MANOVA result, demonstrating that the sum of the three metabolites could differentiate each individual at any given day of the time interval. Expanding upon previous studies, this experiment aims to establish a method of metabolite monitoring as opposed to single-point analyses for application to biometric identification from the skin surface. [ABSTRACT FROM AUTHOR]

A variety of novel naphthimindazol‐N‐oxides and naphththiazol‐N‐oxide have been prepared in a simple two‐step process. The first step involves the reaction of 1‐chloro‐2,4‐dinitronaphthalene with glycine, alanine, glycolic acid, thioglycolic acid, and their methyl esters affording substitution products, the subsequent treatment of which with base furnishes naphthimindazol‐N‐oxide and naphththiazol‐N‐oxide derivatives. Stepwise reaction mechanisms via carbanions, nitrogen anions, and spiro Meisenheimer intermediates are proposed. The action of 10% NaOH in dioxane on the substitution products was measured spectrophotochemically, and the kinetic studies suggested that the N‐naphthyl glycine and N‐naphthyl alanine follow a second‐order rate law while S‐naphthyl thioglycolic acid is accurately first‐order kinetics. [ABSTRACT FROM AUTHOR]

Vip3Aa, secreted by Bacillus thuringiensis, is effective at controlling major agricultural pests such as Spodoptera frugiperda. However, to control Vip3Aa resistance evolved in the field by different lepidoptera species, an in–depth study of sequence––structure––activity relationships is necessary to design new Vip3Aa variants. In this study, the four specific loops (β4–β5 loop, β9–β10 loop, β12–β13 loop, and β14–β15 loop) in domain III were selected and four loop mutants were constructed by replacing all residues in each specific loop with alanine. We obtained soluble proteins for three of the loop mutants, excluding the β9–β10 loop. These loop mutants have been characterized by toxicity bioassays against S. frugiperda, proteolytic processing, and receptor binding. These results indicate that the β4–β5 loop and β14–β15 loop are involved in receptor binding and Vip3Aa toxicity. Based on this, we constructed numerous mutants and obtained three single mutants (Vip3Aa–S366T, Vip3Aa–S366L, and Vip3Aa–R501A) that exhibited significantly increased toxicity of 2.61–fold, 3.39–fold, and 2.51–fold, respectively. Compared to Vip3Aa, the receptor affinity of Vip3Aa–S366T and Vip3Aa–S366L was significantly enhanced. Furthermore, we also analyzed and aligned the three–dimensional structures of the mutants and Vip3Aa. In summary, these results indicate that the loops in domain III have the potential to be targeted to enhance the insecticidal toxicity of the Vip3Aa protein. [ABSTRACT FROM AUTHOR]

Some aquatic invertebrates contain free d -alanine. We previously showed copious amounts of free d -glutamate, a novel d -amino acid, in the tissue of the male reproductive organs of Marsupenaeus japonicus. Herein, we clarified the distribution and potential role of d -glutamate and d -alanine in male reproductive tissues, namely the testis, vas deferens and seminal receptacle at different growth stages of M. japonicus. The percentage of d -glutamate to total glutamate was over 50% in these tissues. In particular, the content of d -glutamate was the most abundant in the vas deferens, the ratio of d -glutamate to total glutamate was approximately 80%. In contrast, d -alanine content was the lowest in the vas deferens among these tissues. d -Glutamate content was the highest when the prawn weighed 12 g, indicating that d -glutamate is actively synthesized in the younger stage. Our findings suggest that d -glutamate plays an important role in the reproductive functions of M. japonicus. [ABSTRACT FROM AUTHOR]

Cupriavidus necator is a versatile microbial chassis to produce high-value products. Blocking the poly-β-hydroxybutyrate synthesis pathway (encoded by the phaC1AB1 operon) can effectively enhance the production of C. necator, but usually decreases cell density in the stationary phase. To address this problem, we modified the hexose utilization pathways of C. necator in this study by implementing strategies such as blocking the Entner–Doudoroff pathway, completing the phosphopentose pathway by expressing the gnd gene (encoding 6-phosphogluconate dehydrogenase), and completing the Embden–Meyerhof–Parnas pathway by expressing the pfkA gene (encoding 6-phosphofructokinase). During heterotrophic fermentation, the OD600 of the phaC1AB1-knockout strain increased by 44.8% with pfkA gene expression alone, and by 93.1% with gnd and pfkA genes expressing simultaneously. During autotrophic fermentation, gnd and pfkA genes raised the OD600 of phaC1AB1-knockout strains by 19.4% and 12.0%, respectively. To explore the effect of the pfkA gene on the production of C. necator, an alanine-producing C. necator was constructed by expressing the NADPH-dependent L-alanine dehydrogenase, alanine exporter, and knocking out the phaC1AB1 operon. The alanine-producing strain had maximum alanine titer and yield of 784 mg/L and 11.0%, respectively. And these values were significantly improved to 998 mg/L and 13.4% by expressing the pfkA gene. The results indicate that completing the Embden–Meyerhof–Parnas pathway by expressing the pfkA gene is an effective method to improve the growth and production of C. necator. [ABSTRACT FROM AUTHOR]

Peptidoglycan is an essential component of the bacterial cell envelope that contains glycan chains substituted by short peptide stems. Peptide stems are polymerized by D,Dtranspeptidases, which make bonds between the amino acid in position four of a donor stem and the third residue of an acceptor stem (4-3 cross-links). Some bacterial peptidoglycans also contain 3-3 cross-links that are formed by another class of enzymes called L,D-transpeptidases which contain a YkuD catalytic domain. In this work, we investigate the formation of unusual bacterial 1-3 peptidoglycan cross-links. We describe a version of the PGFinder software that can identify 1-3 crosslinks and report the high-resolution peptidoglycan structure of Gluconobacter oxydans (a model organism within the Acetobacteraceae family). We reveal that G. oxydans peptidoglycan contains peptide stems made of a single alanine as well as several dipeptide stems with unusual amino acids at their Cterminus. Using a bioinformatics approach, we identified a G. oxydans mutant from a transposon library with a drastic reduction in 1-3 cross-links. Through complementation experiments in G. oxydans and recombinant protein production in a heterologous host, we identify an L,D-transpeptidase enzyme with a domain distantly related to the YkuD domain responsible for these non-canonical reactions. This work revisits the enzymatic capabilities of L,D-transpeptidases, a versatile family of enzymes that play a key role in bacterial peptidoglycan remodelling. [ABSTRACT FROM AUTHOR]

Background: To determine plasma free amino acid (FAA) and carnitine levels in pregnant women with hydatidiform mole (HM). Materials and Methods: Twenty-three pregnant women with HM, and 24 healthy pregnant women as controls were enrolled in the study. FAA and carnitine concentrations were measured in plasma using liquid chromatography/tandem mass spectrometry (LC-MS). Results: The levels of alanine, arginine, and valine from the 14 amino acids examined were significantly lower in the HM group than in the healthy group (p = 0.019, p = 0.009, and p = 0.03, respectively). In addition, several carnitines, C8DC, C16:1, and C18, of the 27 carnitines examined were significantly higher in the HM group than in the control group (p = 0.021, p = 0.03, and p = 0.021, respectively). Conclusions: This study demonstrated that a decrease in some plasma FAAs and an increase in some plasma carnitine levels might be effective in the pathogenesis of HM. [ABSTRACT FROM AUTHOR]

Microalgae have positioned themselves as an innovative and sustainable source of bioactive compounds and high nutritional value. The selection of a suitable food carrier is important to ease its consumption, and to preserve bioactivity through food processing. The aim of this study was to assess the suitability of different microalgae in baked products. Crackers and grissini were produced following a specific formulation, with percentages ranging from 1.5 to 3.5% of flour substituted with Spirulina, Chlorella, and Tetraselmis dry biomass in the formulas. Physico-chemical, nutritional, and sensorial characterization was carried out. The incorporation of microalgae led to increased nutritional values, including antioxidant capacity (AOX), total phenolic content (TPC) and protein content with an amino acids' identification and quantification. Grissini with Chlorella at 3.5% and crackers with Spirulina at 1.5% levels, showed a higher overall acceptance within the panelists. For amino acid content, Spirulina crackers were shown to be rich in alanine, aspartate, and tryptophan, while Chlorella grissini stood out for being particularly rich in isoleucine, leucine, lysine, and valine. Thus, Spirulina and Chlorella could be a sustainable ingredient to formulate baked goods with an enhanced nutrimental matrix without altering their acceptability to consumers. [ABSTRACT FROM AUTHOR]

Fresh and dried Cordyceps sinensis are widely used by the public for medicinal and health purposes. However, the differences between them have not been examined. In this study, fresh wild and artificial C. sinensis (WFC and AFC) were dried to obtain dried wild and artificial C. sinensis (WDC and ADC). Non-targeted GC-MS was used to analyze the metabolic profile characteristics of the four groups of samples. The results showed that air drying significantly altered the composition and content of C. sinensis, mainly in the form of higher abundance of organic acids and derivatives and lower abundance of lipids and lipid-like molecules in fresh C. sinensis. Hierarchical cluster analysis (HCA) and quantitative analyses showed that air drying increased the abundance of Valine, Zinniol, Urocanate, Vulpinic acid, and Uridine 5'-diphosphate, and decreased Xanthotoxol, Vitexin-4-o-glucoside, Val-trp, and Wogonin. These differentially accumulated metabolites (DAMs) were also shown to be potential biomarkers for C. sinensis. KEGG enrichment analysis identified lysine biosynthesis as the most significantly enriched pathway. Annotation of these DAMs to lysine biosynthesis revealed that citrate cycle and pyruvate metabolism entered lysine biosynthesis via 2-oxohlutarate and Homocitrate, respectively, resulting in significant enrichment of L-saccharopine and L-lysine content was significantly higher. Alanine, aspartate, and Glutamate metabolism synthesized more L-aspartate to promote L-lysine synthesis. Thus, high levels of L-lysine result in lysine degradation and pymolysine, which are the most active metabolic pathways during the drying of fresh C. sinensis and indirectly lead to differences in metabolic profiles. [ABSTRACT FROM AUTHOR]