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Biofilm formation is a survival strategy by which microorganisms adapt to environmental challenges. It is regulated by various signals, such as the second messenger c-di-GMP. We previously found that the Flm chemosensory pathway could respond to chemical signals and regulate biofilm formation. This regulation is independent of c-di-GMP. A previous study revealed that the response regulator FlmD is involved in biofilm formation; however, how chemical signals are transmitted downstream of FlmD remained unclear. In the present study, transcriptome analysis and gel shift assay reveal that SoxR, a transcriptional activator of the efflux transporter acrAB-tolC operon, mediates the downstream signaling of FlmD. Phosphorylated FlmD interacts with SoxR and disrupts the interaction between SoxR and the acrAB-tolC operon. It causes a decrease in the expression of acrAB-tolC operon. The downregulation of acrA, acrB, or tolC gene expression results in making less biofilm formation. In conclusion, we identified that the transcription regulator SoxR plays a role in the c-di-GMP independent regulation of biofilm formation in Comamonas testosteroni. [ABSTRACT FROM AUTHOR]

Abstract: Scheelite-type Eu3+-doped CaMoO4 red phosphor with uniform micro-assemblies has been successfully synthesized via a facile hydrothermal method at 120°C for 10h. The Eu3+-doped CaMoO4 microstructures were assembled by small nanostructures and the morphology of materials was found to be manipulated by dropping different alkalis into the stock solution for the first time. The structure, morphology, and luminescent property were characterized and investigated by techniques of X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and photoluminescence (PL). The luminescent investigations confirmed that the Eu3+ ions have been effectively doped into CaMoO4 nanostructures. The successfully achieved Eu3+-doped CaMoO4 nanostructures will be potential in technological applications on near UV chip-based white light emitting diode (WLED). [Copyright &y& Elsevier]

Breast cancer is one of the most common malignant tumors worldwide. SLC7A2 is abnormally expressed in multiple cancers. However, its potential in triple negative breast cancer (TNBC) is still unclear. The purpose of this study was to investigate the roles of SLC7A2 and its underlying molecular mechanisms in TNBC. mRNA expression was detected by RT-qPCR. Protein expression was detected by western blot. Co-localization of ACOX1 and TCF1 was determined using FISH assay. Histone crotonylation was performed using in vitro histone crotonylation assay. Functional analysis was performed using CCK-8 and flow cytometry assays. Xenograft assay was conducted to further verify the role of SLC7A2 in TNBC. CD8A expression was detected using immunohistochemistry. We found that SLC7A2 is downregulated in TNBC tumors. Low levels are associated with advanced stages and lymph node metastasis. SLC7A2 expression is positively correlated with CD8A. SLC7A2-mediated lysine catabolism drives the activation of CD8+ T cells. Moreover, SLC7A2 promotes histone crotonylation via upregulating ACOX1. It also promotes interaction between ACOX1 and TCF1, thus promoting antitumor T cell immunity. Additionally, overexpression of SLC7A2 activates CD8+ T cells and enhances the chemosensitivity of anti-PD-1 therapies in vivo. In conclusion, SLC7A2 may function as an antitumor gene in TNBC by activating antitumor immunity, suggesting SLC7A2/ACOX1/TCF1 signaling as a promising therapeutic strategy.

Background: Gut-brain axis might play an important role in cognitive impairments by various diseases including Alzheimer's disease (AD)., Objective: To investigate the differences in gut microbial composition, intestinal barrier function, and systemic inflammation in patients with AD or mild cognitive impairment (MCI), and normal control (NC) cases., Methods: A total of 118 subjects (45 AD, 38 MCI, and 35 NC) were recruited. Cognitive function was assessed using Mini-Mental State Examination (MMSE), and Montreal Cognitive Assessment Scale (MoCA). Functional ability was assessed using Activity of Daily Living Scale (ADL). The composition of gut microbiome was examined by 16S rRNA high-throughput sequencing. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) was used to predict functional transfer of gut microbiota. Gut barrier dysfunction was evaluated by measuring the levels of diamine oxidase (DAO), D-lactic acid (DA), and endotoxin (ET). The serum high-sensitivity C-reactive protein (hs-CRP) level was used to indicate systemic inflammation., Results: Compared with normal controls, patients with cognitive impairments (AD and MCI) had lower abundance of Dorea and higher levels of DAO, DA, and ET. Kyoto Encyclopedia of Genes and Genomes (KEGG) results showed that the pathways related to glycan biosynthesis and metabolism increased in MCI patients, while the ones related to membrane transport decreased. The abundance of Bacteroides and Faecalibacterium was negatively correlated with the content of ET, and positively correlated with the scores of MMSE and MoCA. The hs-CRP levels were similar among the three groups. A significant negative correlation was observed between the severity of gut barrier dysfunction and cognitive function., Conclusion: Cognitive impairments might be associated with gut microbial dysbiosis and intestinal barrier dysfunction., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Pei, Lu, Li, Jiang and Wang.)

Transition metal dichalcogenides (TMDs) are regarded as promising cathode materials for zinc-ion storage owing to their large interlayer spacings. However, their capabilities are still limited by sluggish kinetics and inferior conductivities. In this study, a facile one-pot solvothermal method is exploited to vertically plant piezoelectric 1T MoSe 2  nanoflowers on carbon cloth (CC) to fabricate crystallographically textured electrodes. The self-built-in electric field owing to the intrinsic piezoelectricity during the intercalation/deintercalation processes can serve as an additional piezo-electrochemical coupling accelerator to enhance the migration of Zn 2+ . Moreover, the expanded interlayer distance (9-10 Å), overall high hydrophilicity, and conductivity of the 1T phase MoSe 2  also promoted the kinetics. These advantages endow the tailored 1T MoSe 2 /CC nanopiezocomposite with feasible Zn 2+ diffusion and desirable electrochemical performances at room and low temperatures. Moreover, 1T MoSe 2 /CC-based quasi-solid-state zinc-ion batteries are constructed to evaluate the potential of the proposed material in low-temperature flexible energy storage devices. This work expounds the positive effect of intrinsic piezoelectricity of TMDs on Zn 2+ migration and further explores the availabilities of TMDs in low-temperature wearable energy-storage devices., (© 2022 Wiley-VCH GmbH.)

The facultative anaerobic and strict anaerobic microorganisms enriched and acclimated during the anaerobic digestion process are crucial for the efficiency of the anaerobic digestion system. Most of the problems encountered during running anaerobic digestion processes could be effectively improved via stimulation of microbial metabolic activity. Benefited from the rapid development of microbiome techniques, deeper insights into the microbial diversity in anaerobic digestion systems, e.g. the microbe-microbe interactions and microbe-environment interactions, have been gained. A complex and intricate metabolic network exists in the anaerobic digestion system of solid organic wastes. However, little is known about these interactions and the underlying mechanisms. This review briefly summarized the representative interactions between microbial communities during anaerobic digestion process discovered to date. In addition, typical issues encountered during the anaerobic digestion of solid organic wastes and how microbes can tackle and alleviate these issues were discussed. Finally, future priorities on microbiome research were proposed based on present contribution of microbiome analysis in anaerobic digestion system.

Aquatic plants and the epiphytic microorganisms are important contributors to the purification of constructed wetlands. Taking the dragon-shaped water system of Beijing Olympic Park as a model, this study analyzed the structure and function of the microbial communities reside the sediment, the water body and the rhizosphere and phyllosphere of three submerged plants-Vallisneria natans, Myriophyllum verticillatum, and Potamogeton pectinatus using high-throughput sequencing technology. The results showed that the microbial diversity from the highest to the lowest were samples from sediment, plant rhizosphere, plant phyllosphere and water. The microbial diversity of plant phyllosphere samples were significantly higher than those of the water body. LEfSe analysis showed that different habitats enriched different microbial groups. The sediments mainly enriched anaerobic microbes, while the water body and the phyllosphere of plants mainly enriched aerobic microbes, and the rhizosphere of plants had the both. Functional prediction analysis showed that the abundance of denitrification marker genes in phyllosphere samples was higher than that in samples from rhizosphere, sediment and water body, and the abundance of denitrification marker genes in phyllosphere samples of M. verticillatum and P. pectinatus was higher than that of V. natans. This study could serve as a guidance for the selection of submerged plants and functional microorganisms for constructed wetlands.

A variety of lithiated calix[ n ]arenes, for which n = 6 or 8, have been isolated, structurally characterized, and evaluated as catalysts for the ring-opening polymerization (ROP) of the cyclic esters ε-caprolactone (ε-CL), δ-valerolactone (δ-VL), and rac -lactide ( r -LA). In particular, interaction of p - tert -butylcalix[6]areneH 6 (L 6 H 6 ) with LiO t Bu in THF led to the isolation of [Li 14 (L 6 H) 2 (CO 3 ) 2 (THF) 6 (OH 2 ) 6 ]·14THF ( 1 ·14THF), the core of which has a chain of five Li 2 O 2 diamonds. Similar use of p - tert -butylcalix[8]areneH 8 (L 8 H 8 ) afforded [Li 10 (L 8 )(OH) 2 (THF) 8 ]·7THF ( 2 ·7THF), where the core is composed of a six-rung Li-O ladder. Use of debutylated calix[8]areneH 8 (deBuL 8 H 8 ) led to an elongated dimer [Li 18 (deBuL 8 ) 2 (O t Bu) 2 (THF) 14 ]·4THF ( 3 ·4THF) in which the calix[8]arenes possess a wavelike conformation forming bridges to link three separate Li x O y clusters (where x and y = 6, ignoring the THF donor oxygens). Interaction of L 8 H 8 with LiOH·H 2 O afforded [Li 4 (L 8 H 4 )(OH 2 ) 4 (THF) 6 ]·5.5THF ( 4 ·5.5THF), where intramolecular H-bond interactions involving Li, O, and H construct a cage in the core of the structure with six- and eight-membered rings. Lastly, addition of Me 3 Al to the solution generated from L 8 H 8 and LiO t Bu led to the isolation of [(AlMe 2 ) 2 Li 20 (L 8 H 2 ) 2 (OH 2 ) 4 (O 2- ) 4 (OH) 2 (NCMe) 12 ]·10MeCN ( 5 ·10MeCN) in which Li, O, Al, and N centers build a polyhedral core. These complexes have been screened for their potential to act as precatalysts in the ring-opening polymerization (ROP) of ε-CL, δ-VL, and r -LA. For the ROP of ε-CL, δ-VL, and r -LA, systems 1 - 4 exhibited moderate activity at 130 °C over 8 h. In the case of ROP using the mixed-metal (Li/Al) system 5 , better conversions and high molecular weight polymers were achieved. In the case of the ROP of ω-pentadecalactone (ω-PDL), the systems proved to be inactive under the conditions employed herein.

Interaction of p-tert-butylcalix[8]areneH8 (L(8) H8 ) with [NaVO(OtBu)4 ] (formed in situ from VOCl3 ) afforded the complex [Na(NCMe)5 ][(VO)2 L(8) H]⋅4 MeCN (1⋅4 MeCN). Increasing [NaVO(OtBu)4 ] to 4 equiv led to [Na(NCMe)6 ]2 [(Na(VO)4 L(8) )(Na(NCMe))3 ]2 ⋅10 MeCN (2⋅10 MeCN). With adventitious oxygen, reaction of 4 equiv of [VO(OtBu)3 ] with L(8) H8 afforded the alkali-metal-free complex [(VO)4 L(8) (μ(3) -O)2 ] (3); solvates 3⋅3 MeCN and 3⋅3 CH2 Cl2 were isolated. For the lithium analogue, the order of addition had to be reversed such that lithium tert-butoxide was added to L(8) H8 and then treated with 2 equiv of VOCl3 ; crystallisation afforded [(VO2 )2 Li6 [L(8) ](thf)2 (OtBu)2 (Et2 O)2 ]⋅Et2 O (4⋅Et2 O). Upon extraction into acetonitrile, [Li(NCMe)4 ][(VO)2 L(8) H]⋅8 MeCN (5⋅8 MeCN) was formed. Use of the imido precursors [V(NtBu)(OtBu)3 ] and [V(Np-tolyl)(OtBu)3 ] and L(8) H8 , afforded [tBuNH3 ][{V(p-tolylN)}2 L(8) H]⋅3 1/2 MeCN (6⋅3 1/2 MeCN). The molecular structures of 1 to 6 are reported. Complexes 1, 3, and 4 were screened as precatalysts for the polymerisation of ethylene in the presence of cocatalysts at various temperatures and for the copolymerisation of ethylene with propylene. Activities as high as 136 000 g (mmol(V) h)(-1) were sometimes achieved; higher molecular weight polymers could be obtained versus the benchmark [VO(OEt)Cl2 ]. For copolymerisation, incorporation of propylene was 7.1-10.9 mol % (compare 10 mol % for [VO(OEt)Cl2 ]), although catalytic activities were lower than [VO(OEt)Cl2 ]., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: To study the adaptation of A. hospitalis W1 to oligotrophic and acidic hot spring environments at the whole genome level., Methods: We annotated the gene functions and constructed metabolic pathways of strain W1 by using different databases, such as NCBI non-redundant database (NRDB), UniProt, Sulfolobus protein database and Kyoto Encyclopedia of Genes and Genomes (KEGG). The metabolic pathways were polished according to the results of comparative genomics., Results: Strain W1 grew autotrophically by fixing CO2 as carbon source through 3-hydroxypropionate/4-hydroxybutyrate or dicarboxylate-4-hydroxybutyrate cycle, and gained energy for growth by oxidation of reduced inorganic sulfur compounds (RISCs). Strain W1 differenced from A. ambivalens because its genome did not possess sulfur-metabolizing genes encoding sulfite: acceptor oxidoreductase, adenosine phosphosulfate reductase, sulfate adenylyl transferase and phosphoadenosine phosphosulfate reductase. Glucose was metabolized by strain W1 through non- phosphorylated Entner-Doudoroff pathway and tricarboxylic acid cycle. In addition, the sugar and amino acids transporters, as well as related hydrolysis enzymes were identified in the genome. These results suggest that strain W1 could also grow facultative autotrophically. Strain W1 cannot use H2 as electron donor due to lack of hydrogenase encoding genes., Conclusion: The versatile metabolic patterns afforded A. hospitalis W1 the ability to adapt to oligotrophic and acidic hot spring environments. Furthermore, the unique metabolic features of strain W1 will help to better understand the metabolic diversities of Acidianus.

Objective: The work aimed to isolate and culture the acidophilic and moderately thermophilic microorganisms for leaching the sulfide ore., Methods: We enriched and incubated iron- or sulfur-oxidizing strains from muddy water of acuric hot spring utilizing ferrous irons or elemental sulfur as substrates. Then, we identified the strains by their morphological, physiological, biochemical properties and phylogenetic positions, and estimated their bioleaching potential according to their oxidation rate of pyrite., Results: Two acidophilic, aerobic and facultative heterotrophic bacterial strains, Costa C and Costa E, were isolated from the samples of sulfuric hot springs of Costa Rica. Cells of the two strains were gram-positive, spore-forming and rod-shaped [(0.4 - 0.6) microm x (2.5 - 4.0) microm and (0.4 - 0.7) microm x (2.4 - 4.9) microm, respectively]. Strain Costa C grew at a temperature range of 30 degrees C - 55 degrees C and a pH range of 1.2 - 5.0, optimally at 50 degrees C and 2.8. Strain Costa E grew at a temperature range of 30 degrees C - 55 degrees C and at a pH range of 1.4 - 5.0, optimally at 40 degrees C and 2.8. Two strains could autotrophically grow on inorganic substrates such as ferrous irons, element sulfur and K2 S4 O6 and also could utilize organic substrates like yeast extract for heterotrophic growth. Phylogenetic analysis based on 16S rRNA gene sequences alignment demonstrated that the highest similarity between strain Costa C, Costa E and other species of the genus Sulfobacillus was above 99%., Conclusion: Based on morphological, physiological and biochemical analysis, Costa C and Costa E can be affiliated to the genus Sulfobacillus, for which the names Sulfobacillus sp. strain Costa C and Sulfobacillus sp. strain Costa E were proposed. Both strains could oxidize pyrite, and the oxidation rates arrived 63.0 mg/L x d and 56.8 mg/L x d, respectively.

Objective: The work aimed to obtain pyrene-degrading bacterial consortium and use it for bioremediation of polycyclic aromatic hydrocarbons-contaminated soil., Methods: We enriched and incubated a bacterial consortium utilizing pyrene as the sole carbon source from the contaminated soil of Beijing Coking Chemical Plant. We analyzed the degrading ability and growth of the consortium by high performance liquid chromatography (HPLC) and spectrophotometer. We investigated the degradation activities of the consortium after several times transfer and freeze-drying deposit. We also investigated the shift of bacterial consortium composition after several times transfer by combining of culture-dependent and culture-independent methods. We constructed and analyzed the 16S rRNA gene clone libraries at different transfer times (3 times PYR-3, 6 times PYR-6 and 9 times PYR-9) for monitoring the bacterial population changes., Results: The degradation rate of pyrene, phenanthrene and fluoranthene reached 89%, 86% and 49% respectively after incubation of the consortium for 12 days. The degradation activities of the consortium were stable after several times transfer and freeze-drying deposit. We isolated nine strains from the consortium, affiliated to genus of Achromobacter, Bacillus, Arthrobacter, Exiguobacterium and Parapedobacter. Phylogenetic analyses showed that Proteobacteria were the main group at contaminated soil sample (100%) and bacterial consortium incubated in pyrene (PYR-3, 83%). Bacterial community structure was shifted and biodiversity was increased during the transfer process, the proportions of gamma-Proteobacteria was decreased from 77% (PYR-3) to 33% (PYR-6) and 18% (PYR-9), while beta-Proteobacteria increased from 13% (PYR-3) to 36% (PYR-6) and 55% (PYR-9)., Conclusion: The bacterial consortium could utilize pyrene as sole carbon and energy source for growth and the degradation ability for pyrene was stable.

Objective: In order to study the microbial diversity and the characteristics of cultivable microorganisms in bioleaching reactors., Methods: Both conventional culture technique and analysis of a 16S rRNA sequence library were used. The pure cultures were isolated by enriching the samples under different cultural conditions. The morphology characters, physiology and biochemistry characters, genetic characters and oxidation efficiency to different minerals of cultured isolates were analyzed., Results: The microbial community in bioleaching reactors identified through the gene clone libraries were closely related to bacteria including Leptospirillum sp., Sulfobacillus sp., Acidithiobacillus sp., Spingomonas sp. and Archaea including Sulfolobus sp., Ferroplasma sp. Five strains were isolated after enriching and culturing, which were corresponding to Acidithiooxidians caldus, Acidithiooxidians thiooxidans, Acidithiooxidans ferrooxidans, Leptospirillum ferriphilum and Sulfobacillus thermosulfidooxidans. These isolates could oxidize sulfur or Fe2+ and different sulfide ores., Conclusion: The bioleaching reactors were dominated by a small number of microbial species that were commonly found at thermoacidophilic environments.