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Amidines are a structural surrogate for peptide bonds, yet have received considerably little attention in peptides due to limitations in existing methods to access them. The synthetic strategy developed in this study represents the first robust and general procedure for the introduction of amidines into the peptide backbone. We exploit and further develop the utility and efficiency of thioimidate protecting groups as a means to side-step reactivity that ultimately renders existing methods unsuitable for the installation of amidines along the main-chain of peptides. This work is significant because it describes a generally applicable path to access unexplored peptide designs and architectures for new therapeutics made possible by the unique properties of amidines.

The continuous increase in the global energy demand has diminished fossil fuel reserves and elevated the risk of environmental deterioration and human health. Biorefinery processes involved in producing bio-based energy-enriched chemicals have paved way to meet the energy demands. Compared to the thermochemical processes, fungal system biorefinery processes seems to be a promising approach for lignocellulose conversion. It also offers an eco-friendly and energy-efficient route for biofuel generation. Essentially, ligninolytic white-rot fungi and their enzyme arsenals degrade the plant biomass into structural constituents with minimal by-products generation. Hemi- or cellulolytic enzymes from certain soft and brown-rot fungi are always favoured to hydrolyze complex polysaccharides into fermentable sugars and other value-added products. However, the cost of saccharifying enzymes remains the major limitation, which hinders their application in lignocellulosic biorefinery. In the past, research has been focused on the role of lignocellulolytic fungi in biofuel production; however, a cumulative study comprising the contribution of the lignocellulolytic enzymes in biorefinery technologies is still lagging. Therefore, the overarching goal of this review article is to discuss the major contribution of lignocellulolytic fungi and their enzyme arsenal in global biofuel research and multiproduct biorefinery.

The health catastrophe originated by COVID-19 pandemic construed profound impact on a global scale. However, a plethora of research studies corroborated convincing evidence conferring severity of infection of SARS-CoV-2 with the aberrant gut microbiome that strongly speculated its importance for development of novel therapeutic modalities. The intense exploration of probiotics has been envisaged to promote the healthy growth of the host, and restore intestinal microecological balance through various metabolic and physiological processes. The demystifying effect of probiotics cannot be defied, but there exists a strong skepticism related to their safety and efficacy. Therefore, molecular signature of probiotics termed as “postbiotics” are of paramount importance and there is continuous surge of utilizing postbiotics for enhancing health benefits, but little is explicit about their antiviral effects. Therefore, it is worth considering their prospective role in post-COVID regime that pave the way for exploring the pastoral vistas of postbiotics. Based on previous research investigations, the present article advocates prospective role of postbiotics in alleviating the health burden of viral infections, especially SARS-CoV-2. The article also posits current challenges and proposes a futuristic model describing the concept of “precision postbiotics” for effective therapeutic and preventive interventions that can be used for management of this deadly disease.

The progressive development of peptides from reaction vessels to life-saving drugs via rigorous preclinical and clinical assessments is fascinating. Peptide therapeutics have gained momentum with the evolution of techniques in peptide chemistry, such as microwave irradiation in solid- and solution-phase synthesis, ligation chemistry, recombinant synthesis, and amalgamation with synthetic tools, including metal catalysis. Diverse emerging technologies, such as DNA-encoded libraries (DELs) and display techniques, are changing the status quo in the discovery of peptide therapeutics. In this review, we analyzed US Food and Drug Administration (FDA)-approved peptide drugs and those in clinical trials, highlighting recent advances in peptide-based drug discovery.

Human gut microbiota contributes to host nutrition and metabolism, sustains intestinal cell proliferation and differentiation, and modulates host immune system. The alterations in their composition lead to severe gut disorders, including inflammatory bowel disease (IBD) or inflammatory bowel syndrome (IBS). IBD including ulcerative colitis (UC) and Crohn's disease (CD) are gamut of chronic inflammatory disorders of gut, mediated by complex interrelations among genetic, environmental, and internal factors. IBD has debateable aetiology, however in recent years, exploring the central role of a tri-directional relationship between gut microbiota, mucosal immune system, and intestinal epithelium in pathogenesis is getting the most attention. Increasing incidences and early onset explains the exponential rise in IBD burden on health-care systems. Industrialization, hypersensitivity to allergens, lifestyle, hygiene hypothesis, loss of intestinal worms, and gut microbial composition, explains this shifted rise. Hitherto, the interventions modulating gut microbiota composition, microfluidics-based

Human gut microbiota (GM) includes a complex and dynamic population of microorganisms that are crucial for well-being and survival of the organism. It has been reported as diverse and relatively stable with shared core microbiota, including Bacteroidetes and Firmicutes as the major dominants. They are the key regulators of body homeostasis, involving both intestinal and extra-intestinal effects by influencing many physiological functions such as metabolism, maintenance of barrier homeostasis, inflammation and hematopoiesis. Any alteration in GM community structures not only trigger gut disorders but also influence other organs and cause associated diseases. In recent past, the GM has been defined as a 'vital organ' with its involvement with other organs; thus, establishing a link or a bi- or multidirectional communication axis between the organs via neural, endocrine, immune, humoral and metabolic pathways. Alterations in GM have been linked to several diseases known to humans; although the exact interaction mechanism between the gut and the organs is yet to be defined. In this review, the bidirectional relationship between the gut and the vital human organs was envisaged and discussed under several headings. Furthermore, several disease symptoms were also revisited to redefine the communication network between the gut microbes and the associated organs.

Earlier, we have found that the enteropathogenic Yersinia enterocolitica have evolved the survival mechanisms that regulate the expression of laccase-encoding genes in the gut. The present study aims to characterize the purified recombinant laccase from Y. enterocolitica strain 8081 biovar 1B and understand its effect on the midgut of cotton bollworm, Helicoverpa armigera (Hubner) larvae. The recombinant laccase protein showed high purity fold and low molecular mass (~ 43 kDa). H. armigera larvae fed with laccase protein showed a significant decrease in body weight and damage in the midgut. Further, transmission electron microscopy (TEM) studies revealed the negative effect of laccase protein on trachea, malpighian tubules, and villi of the insect. The proteome comparison between control and laccase-fed larvae of cotton bollworm showed significant expression of proteolytic enzymes, oxidoreductases, cytoskeletal proteins, ribosomal proteins; and proteins for citrate (TCA cycle) cycle, glycolysis, stress response, cell redox homeostasis, xenobiotic degradation, and insect defence. Moreover, it also resulted in the reduction of antioxidants, increased melanization (insect innate immune response), and enhanced free radical generation. All these data collectively suggest that H. armigera (Hubner) larvae can be used to study the effect of microbes and their metabolites on the host physiology, anatomy, and survival.

In this study, some important chemical parameters of underground water of the area were evaluated for the criteria of irrigation water quality. Higher values of pH, EC, SAR and RSC make the underground water unfit for irrigation purposes. One hundred fifty underground irrigation water samples were collected from various tehsils of Nagaur district during 2018-19. Based on salinity the classes of irrigation water were recorded normal water (0.66%), Low salinity water (39.34%), Medium salinity water (60%) and based on sodicity the classes of irrigation water were recorded normal water (2%), Low sodicity water (74.66%), medium sodicity water (23.34%) and based on alkalinity the classes of irrigation water were recorded non alkaline water (30%), Normal water (2%), Low alkalinity water (44.66%), medium alkalinity water (16%), high alkalinity water (7.34%). Majority of the water samples are fall under low to medium suitable category of water for irrigation purposes.

Bioethanol production using paper wastes seems a promising approach towards sustainable energy, but mainly hindered by hazardous ink. Therefore, in our experimental plan various methods were applied for the deinking of waste newspapers, laser printed papers and examination papers. A newly designed paper pulper reduced the pulping time from 6 h to 2 h. Cellulase (15 FPU/g) from Aspergillus oryzae MDU-4 was found effective for the deinking of newspapers, whereas laccase isozymes (150 U/g) from Ganoderma lucidum MDU-7 along with 2 mM HOBt was preferred for the ink removal and degradation from the examination papers. Ozonation in the presence of Tween-80 was found to be efficient in the removal of toxic toners used in laser printing papers. The biologically and physically deinked papers, studied with the help of SEM, TEM, FTIR, and XRD analysis revealed significant changes in the chemical and surface structure. Moreover, the saccharification of deinked papers with the help of an enzymatic consortium of Trichoderma citrinoviride MDU-1 resulted in 305 mg/g, 377 mg/g, and 409 mg/g release of sugars from the newspaper, examination paper, and laser printed paper, respectively. Finally, the enzymatic hydrolysates fermented with Saccharomyces cerevisiae NCIM-3640 produced 3.35 g/L ethanol, with 40.85% ethanol yield.

Smaller oligomeric chaperones of α-crystallins (αA- and αB-) have received increasing attention due to their improved therapeutic potential in preventing protein aggregating diseases. Our previous study suggested that deleting 54–61 residues from the N-terminal domain (NTD) of αB-crystallin (αBΔ54–61) decreases the oligomer size and increases the chaperone function. Several studies have also suggested that NTD plays a significant role in protein oligomerization and chaperone function. The current study was undertaken to assess the effect of deleting conserved 21–28 residues from the activated αBΔ54–61 (to get αBΔ21–28, Δ54–61) on the structure–function of recombinant αBΔ21–28, Δ54–61. The αBΔ21–28, Δ54–61 mutant shows an 80% reduction in oligomer size and 3- to 25-fold increases in chaperone activity against model substrates when compared to αB-WT. Additionally, the αB∆21–28, ∆54–61 was found to prevent β-amyloid (Aβ1–42) fibril formation in vitro and suppressed Aβ1–42-induced cytotoxicity in ARPE-19 cells in a more effective manner than seen with αB-WT or αB∆54–61. Cytotoxicity and reactive oxygen species (ROS) detection studies with sodium iodate (SI) showed that the double mutant protein has higher anti-apoptotic and anti-oxidative activities than the wild-type or αB∆54–61 in oxidatively stressed cells. Our study shows that the residues 21–28 and 54–61 in αB-crystallin contribute to the oligomerization and modulate chaperone function. The deletion of conserved 21–28 residues further potentiates the activated αBΔ54–61. We propose that increased substrate affinity, altered subunit structure, and assembly leading to smaller oligomers could be the causative factors for the increased chaperone activity of αBΔ21–28, Δ54–61.

Fluorinated analogues of the fluorophore pyronin B were synthesized as a new class of amine-reactive drug-like small molecules. In water, 2,7-difluoropyronin B was found to reversibly react with primary amines to form covalent adducts. When this fluorinated analogue is added to proteins, these adducts undergo additional oxidation to yield fluorescent 9-aminopyronins. Irradiation with visible blue light enhances this oxidation step, providing a photochemical method to modify the biological properties of reactive amines. In living HeLa cells, 2,7-difluoropyronin B becomes localized in mitochondria, where it is partially transformed into fluorescent aminopyronins, as detected by spectral profiling confocal microscopy. Further excitation of these cells with the blue laser of a confocal microscope can depolarize mitochondria within seconds. This biological activity was only observed with 2,7-difluoropyronin B and was not detected with analogues such as pyronin B or 9-methyl-2,7-difluoropyronin B. This irradiation with blue light enhances the cellular production of reactive oxygen species (ROS), suggesting that increased ROS in mitochondria promotes the formation of aminopyronins that inactivate biomolecules critical for maintenance of mitochondrial membrane potential. The unique reactivity of 2,7-difluoropyronin B offers a novel tool for photochemical control of mitochondrial biology.

We investigated synthetic amino acid-based approach to design short peptide-based antibiotics. Tautomerically restricted, amphiphilic 1-aryl-l-histidines along with hydrophobic tryptophan were utilized to synthesize the designed peptides. l-Trp-l-His(1-biphenyl)-NHBzl (12e, IC

Background & ObjectiveCovid-19 pandemic has led to multiple waves secondary to mutations in SARS-CoV-2 and emergence of variants of concern (VOC). Clinical characteristics of delta (B.1.617.2) VOC are not well reported. To compare demographic, clinical and laboratory features and outcomes in the second Covid-19 wave in India (delta VOC) with the previous wave we performed a registry-based study.MethodsSuccessive SARS-CoV-2 reverse transcriptase-polymerase chain reaction (RT-PCR) confirmed Covid-19 patients presenting to our Advanced Covid Care hospital were prospectively recruited. In the first phase (wave) from March-December 2020, 1395 of 7476 (18.7%) suspected patients tested positive and 863 (61.89%) hospitalized, while in second wave from January-July 2021 out of 1641 confirmed cases out of 8680 (19.4%) suspected 388 (23.6%) were hospitalized. Details of clinical and laboratory features at admission to hospital, management and outcomes in the two waves have been compared.ResultsIn both cohorts, majority were men and 20% less than 40 years. Prevalence of hypertension, diabetes and cardiovascular diseases was more than 20%. Second wave patients had similar pre-hospitalization symptom duration but had significantly greater cough, fever and shortness of breath and lower SpO2 at presentation with greater lymphopenia, C-reactive proteins, interleukin-6, ferritin, lactic dehydrogenase and transaminases. In the second vs first wave patients, requirement of supplementary oxygen (47.9% vs 34.3%), prone positioning (89.2 vs 38.6%), high flow nasal oxygen(15.7 vs 9.1%), non-invasive ventilation (14.4 vs 9.5%), invasive ventilation (16.2 vs 9.5%), steroids (94.1 vs 85.9%), remdesivir (91.2 vs 76.0%) and anticoagulants (94.3 vs 76.0%) was greater (pConclusionsCovid-19 patients hospitalized during the second wave of the epidemic (delta variant) had more severe disease with greater dyspnea, hypoxia, hematological and biochemical abnormalities compared to first wave patients. They had greater length of stay in intensive care unit, oxygen requirement, non-invasive and invasive ventilatory support. The in-hospital mortality in the second wave was double of the first.

μ-Opioid receptor agonists provide potent and effective acute analgesia; however, their therapeutic window narrows considerably upon repeated administration, such as required for treating chronic pain. In contrast, bifunctional μ/δ opioid agonists, such as the endogenous enkephalins, have potential for treating both acute and chronic pain. However, enkephalins recruit β-arrestins, which correlate with certain adverse effects at μ- and δ-opioid receptors. Herein, we identify the C-terminus of Tyr-ψ[(Z)CF[double bond, length as m-dash]CH]-Gly-Leu-enkephalin, a stable enkephalin derivative, as a key site to regulate bias of both δ- and μ-opioid receptors. Using in vitro assays, substitution of the Leu(5) carboxylate with amides (NHEt, NMe(2), N(Cy)Pr) reduced β-arrestin recruitment efficacy through both the δ-opioid and μ-opioid, while retaining affinity and cAMP potency. For this series, computational studies suggest key ligand–receptor interactions that might influence bias. These findings should enable the discovery of a range of tool compounds with previously unexplored biased μ/δ opioid agonist pharmacological profiles.

The C-terminus fragment (Val-Val-Ile-Ala) of amyloid-β is reported to inhibit the aggregation of the parent peptide. In an attempt to investigate the effect of sequential amino-acid scan and C-terminus amidation on the biological profile of the lead sequence, a series of tetrapeptides were synthesized using MW-SPPS. Peptide D-Phe-Val-Ile-Ala-NH2 (12c) exhibited high protection against β-amyloid-mediated-neurotoxicity by inhibiting Aβ aggregation in the MTT cell viability and ThT-fluorescence assay. Circular dichroism studies illustrate the inability of Aβ42 to form β-sheet in the presence of 12c, further confirmed by the absence of Aβ42 fibrils in electron microscopy experiments. The peptide exhibits enhanced BBB permeation, no cytotoxicity along with prolonged proteolytic stability. In silico studies show that the peptide interacts with the key amino acids in Aβ, which potentiate its fibrillation, thereby arresting aggregation propensity. This structural class of designed scaffolds provides impetus towards the rational development of peptide-based-therapeutics for Alzheimer's disease (AD).

Trametes ljubarskyi produces multiple laccase isozymes under various physicochemical conditions. During co-cultivation condition Rhodotorula mucilaginosa showed inter-specific interactions with T. ljubarskyi and hypersecretion of laccases; however, the underlying molecular mechanism is less-known. The analysis of proteomics data of co-cultivated cultures revealed the mechanism of metabolic coupling during fungal-yeast interactions. The results suggested high score GO terms related to stimulus-response, protein binding, membrane components, transport channels, oxidoreductases, and antioxidants. The SEM studies confirmed the cellular communication and their inter-specific interactions. This study allows us to deepen and refine our understanding of fungal-yeast symbiotic interaction; further, it also establishes a mutual relation by metabolic coupling for 10-fold higher laccase isozyme secretion (6532 U/ml). The purified laccase isozymes showed acidic pH optima (pH 3–4), higher thermo-stability (60 °C), and broad enzyme kinetics (Km) values. Our study also provides an in-depth understanding of laccase isozymes and their potential to degrade synthetic dyes, which may help the fungi to survive in an adverse environment.

Mouse infection models are frequently used to study the host–pathogen interaction studies. However, due to several constraints, there is an urgent need for a simple, rapid, easy to handle, inexpensive, and ethically acceptable in vivo model system for studying the virulence of enteropathogens. Thus, the present study was performed to develop the larvae of Helicoverpa armigera as a rapid-inexpensive in vivo model system to evaluate the effect of Yersinia enterocolitica strain 8081 on its midgut via a label-free proteomic approach. Helicoverpa armigera larvae fed with Yersinia enterocolitica strain 8081 manifested significant reduction in body weight and damage in midgut. On performing label-free proteomic study, secretory systems, putative hemolysin, and two-component system emerged as the main pathogenic proteins. Further, proteome comparison between control and Yersinia added diet-fed (YADF) insects revealed altered cytoskeletal proteins in response to increased melanization (via a prophenoloxidase cascade) and free radical generation. In concurrence, FTIR-spectroscopy, and histopathological and biochemical analysis confirmed gut damage in YADF insects. Finally, the proteome data suggests that the mechanism of infection and the host response in Y. enterocolitica-H. armigera system mimics Yersinia-mammalian gut interactions. All data from current study collectively suggest that H. armigera larva can be considered as a potential in vivo model system for studying the enteropathogenic infection by Y. enterocolitica strain 8081.

Novel derivatives were synthesized using natural scaffold, like phenylpropanoids C(6)–C(3) backbone to reduce unfavorable browning of food due to tyrosinase and oxidative spoilage. Most of the compounds displayed mushroom tyrosinase inhibition better than kojic acid. Compound CE48 exhibited better anti-tyrosinase (IC(50)-29.64 μM) and antioxidant (EC(50)-12.67 μM) activity than the reference compounds, kojic acid (IC(50)-50.30 μM) and ascorbic acid (EC(50)-14.55 μM), respectively. Compounds SAM30, SE78, 11F, and CE48 showed better anti-B. subtilis, anti-S. aureus, and anti-A. niger activity, respectively, compared to their parents. Molecular docking studies between inhibitors and mushroom tyrosinase corroborated the experimental reports, except SAM30 (glide score − 8.117) and SE78 (glide score − 6.151). In silico absorption, distribution, metabolism, excretion/toxicity (ADME/T) and toxicological studies of these newly synthesized compounds exhibited acceptable pharmacokinetic and safety profiles, like good aqueous solubility (− 3.34 to − 7.57), low human oral absorption (e.g., SAM30, SE78, FAM34), low gut–blood barrier permeability [36.67–209.88 nm/s in Cancer coli-2 (Caco-2) cells] and [19.45–91.51 nm/s in Madin-Darby Canine Kidney (MDCK) cells], low blood–brain barrier penetration, non-mutagenicity, and non-carcinogenicity. Interestingly, the synthesized compounds also possessed multifunctional properties, like microbial growth inhibitor, free radicals scavenger, and it also prevented browning of raw fruits and vegetables by inhibiting tyrosinase enzyme. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-020-02636-0.

Pathobionts are opportunistic microbes that emerge as a result of perturbations in the healthy microbiome due to complex interactions of various genetic, exposomal, microbial, and host factors that lead to their selection and expansion. Their proliferations can aggravate inflammatory manifestations, trigger autoimmune diseases, and lead to severe life-threatening conditions. Current surge in microbiome research is unwinding these complex interplays between disease development and protection against pathobionts. This review summarizes the current knowledge of pathobiont emergence with a focus on Clostridioides difficile and the recent findings on the roles of immune cells such as iTreg cells, Th17 cells, innate lymphoid cells, and cytokines in protection against pathobionts. The review calls for adoption of innovative tools and cutting-edge technologies in clinical diagnostics and therapeutics to provide insights in identification and quantification of pathobionts.

The inhibition of amyloid-β (Aβ) aggregation is a promising approach towards therapeutic intervention for Alzheimer's disease (AD). Thirty eight tetrapeptides based upon Aβ

The C-terminus fragment (Val-Val-Ile-Ala) of amyloid-β is reported to inhibit the aggregation of the parent peptide. In an attempt to investigate the effect of sequential amino-acid scan and C-terminus amidation on the biological profile of the lead sequence, a series of tetrapeptides were synthesized using MW-SPPS. Peptide D-Phe-Val-Ile-Ala-NH

Laccases or benzenediol oxygen oxidoreductases (EC 1.10.3.2) are polyphenol multicopper oxidases that are known for their structural and functional diversity in various life forms. In the present study, the molecular and physico-chemical properties (redox-potential and secondary structures) of fungal laccase isozymes (FLIs) isolated from a medicinal mushroom Ganoderma lucidum were analyzed and compared with those of the recombinant bacterial laccases (rLac) obtained from different Yersinia enterocolitica strains. It was revealed that the FLIs contained His-Cys-His as the most conserved residue in its domain I Cu site, while the fourth and fifth residues were variable (Ile, Leu, or Phe). Evidently, the cyclic voltammetric measurements of Glac L2 at Type 1 Cu site revealed greater E° for ABTS/ABTS+ (0.312 V) and ABTS+/ABTS2+ (0.773 V) compared to the E° of rLac. Furthermore, circular dichroism-based conformational analysis revealed structural stability of the FLIs at acidic pH (3.0) and low temperature ( 70 °C). The zymographic studies further confirmed the functional inactivation of FLIs at high temperatures (≥70 °C), predominantly due to domain unfolding. These findings provide novel insight into the evolution of the catalytic efficiency and redox properties of the FLIs, contributing to the existing knowledge regarding stress responses, metabolite production, and the biotechnological utilization of metabolites.

The bio-engineering of nanoparticles for the transportation of various therapeutic agents specifically to brain has sparked a rapidly growing interest in the field of material chemistry. In this study, L-pGlu-(1-benzyl)–L-His–L-ProNH2 (NP-355) and L-pGlu-(2-propyl)–L-His–L-ProNH2 (NP-647) were synthesized and encapsulated in biodegradable poly-lactide-co-glycolide (PLGA) nanoparticles which were further decorated with mucoadhesive surface coating of chitosan. NP-355 and NP-647 which are analogues of thyrotropin releasing hormone, have been reported to demonstrate potential antiepileptic properties against various animal models of seizures. However, their applicability is limited by their short lives due to rapid metabolism and blood brain barrier. The treatment of disorders associated with central nervous system such as epilepsy has been a major challenge for several decades due to difficulty in delivery of drug molecules and imaging agents to brain. To overcome these issues, development of sustained release delivery system for these neuropeptides is proposed which can be administered directly from nose to brain utilizing olfactory nerve channels. The synthesized nanoparticles were evaluated for their physicochemical properties, sustained release properties, toxicity and antiepileptic potential following intranasal administration. The ability of these nanoparticles to reach the brain was evaluated by utilizing quantum dots as fluorescent probes. Our results proved that the polymeric nanoparticles can be used for successful delivery of neurological drugs to the brain.

Opioid peptides are key regulators in cellular and intercellular physiological responses, and could be therapeutically useful for modulating several pathological conditions. Unfortunately, the use of peptide-based agonists to target centrally located opioid receptors is limited by poor physicochemical (PC), distribution, metabolic, and pharmacokinetic (DMPK) properties that restrict penetration across the blood-brain-barrier via passive diffusion. To address these problems, the present manuscript exploits fluorinated peptidomimetics to simultaneously modify PC and DMPK properties, thus facilitating entry into the central nervous system. As an initial example, the present manuscript exploited the Tyr(1)-ψ[(Z)CF=CH]-Gly(2) peptidomimetic to improve PC drug-like characteristics (computational), plasma and microsomal degradation, and systemic and CNS distribution of Leu-enkephalin (Tyr-Gly-Gly-Phe-Leu). Thus, the fluoroalkene replacement transformed an instable in vitro tool compound into a stable and centrally-distributed in vivo probe. In contrast, the Tyr(1)-ψ[CF(3)CH(2)–NH]-Gly(2) peptidomimetic decreased stability by accelerating proteolysis at the Gly(3)–Phe(4) position.

Non-steroidal anti-inflammatory drugs (NSAIDs) can induce small-intestinal injuries through inhibition of prostaglandin synthesis. Gut has an important role in building and maintaining the barriers to avoid the luminal gut microbiota from invading the host, and cytoskeleton plays a crucial role in the maintenance of cellular barrier. The recent advances suggest a bi-directional interaction between the drugs and gut microbiota, where gut microbes can metabolize the drugs, and in response drugs can alter the composition of gut microbiota. In the present study, we evaluated the effect of diclofenac on rat gut, when co-administrated with either Yersinia enterocolitica strain 8081 (an enteropathogen) or Lactobacillus fermentum strain 9338 (a probiotic). The LC-MS/MS based label-free quantitation of rat gut proteins revealed 51.38% up-regulated, 48.62% down-regulated in diclofenac-Y. enterocolitica strain 8081 (D*Y), and 74.31% up-regulated, 25.69% down-regulated in diclofenac-L. fermentum strain 9338 (D*L) experiments. The identified proteins belonged to cytoskeleton, metabolism, heme biosynthesis and binding, stress response, apoptosis and redox homeostasis, immune and inflammatory response, and detoxification and antioxidant defence. Further, the histopathological and biochemical analysis indicated more pronounced histological alterations and oxidative stress (enhanced malonaldehyde and altered antioxidant levels) in D*Y rats than D*L rats, compared to control rats. Elevated plus maze (EPM) test performed to determine the behavioral changes, suggested increased anxiety in D*Y rats than D*L rats, compared to control rats. These results together suggest the differential role of either bacterium in biotransformation of diclofenac, and inflammatory and cellular redox response.

The new structural classes of ultrashort peptides that exhibit potent microbicidal action have potential as future drugs. Herein, we report that C-2 arylated histidines containing tripeptides His(2-Ar)-Trp-His(2-Ar) exhibit potent antifungal activity against Cryptococcus neoformans with high selectivity. The most potent peptide 12f [His(2-biphenyl)-Trp-His(2-biphenyl)] displayed high in vitro activity against C. neoformans (IC50 = 0.35 μg/mL, MIC = MFC = 0.63 μg/mL) with a selectivity index of >28 and 2 times higher potency compared to amphotericin B. Peptide 12f exhibited proteolytic stability, with no apparent hemolytic activity. The mechanism of action study of 12f by confocal laser scanning microscopy and electron microscopy indicates nuclear fragmentation and membrane disruption of C. neoformans cells. Combinations of 12f with fluconazole and amphotericin B at subinhibitory concentration were synergistic against C. neoformans. This study suggests that 12f is a new structural class of amphiphilic pept...

The growing incidents of cryptococcosis in immuno-compromised patients have created a need for novel drug therapies capable of eradicating the disease. The peptide-based drug therapy offers many advantages over the traditional therapeutic agents, which has been exploited in the present study by synthesizing a series of hexapeptides that exhibits promising activity against a panel of Gram-negative and Gram-positive bacteria and various pathogenic fungal strains; the most exemplary activity was observed against Cryptococcus neoformans. The peptides 3, 24, 32 and 36 displayed potent anticryptococcal activity (IC50 = 0.4–0.46 μg/mL, MIC = 0.63–1.25 μg/mL, MFC = 0.63–1.25 μg/mL), and stability under proteolytic conditions. Besides this, several other peptides displayed promising inhibition of pathogenic bacteria. The prominent ones include peptides 18–20, and 26 that exhibited IC50 values ranged between 2.1 and 3.6 μg/mL, MICs of 5–20 μg/mL and MBCs of 10–20 μg/mL against Staphylococcus aureus and methicillin-resistant S. aureus. The detailed mechanistic study on selected peptides demonstrated absolute selectivity towards the bacterial membranes and fungal cells by causing perturbations in the cell membranes, confirmed by the scanning electron microscopy and transmission electron microscopy studies.

We report copper(I)-catalyzed synthesis of 1,2-diaryl histidines via N(1)-arylation of protected 2-aryl histidines in the presence of 8-hydroxyquinoline as ligand and aryl iodides as electrophilic coupling partners, under microwave irradiation at 140 oC. This methodology provides regioselective access to previously inaccessible multi-substituted histidines with intact chirality in high yields. The synthesized 1,2-diarylated histidines are a hitherto unknown class of derivatives with untapped potential in modified amino acids-based peptides and peptidomimetics drug discovery.

Hypertension is highly prevalent in India but frequency of resistant hypertension has not been well studied.We performed a registry-based study at a single center in patients with primary diagnosis of hypertension (n=3073). Details of co-morbidities, medications and blood pressure (BP) control were obtained. Patients with coronary heart disease, cerebrovascular disease and chronic kidney disease were excluded. Resistant hypertension was defined as uncontrolled hypertension (BP ≥140/90) with use of 3 drugs of which one was a diuretic, or any 4 drugs.Mean age of patients was 59±13 years, 47% were women and 26%50y age. Diabetes was in 31.1%, hypothyroidism in 7.9% and chronic obstructive lung disease in 4.3%. The drugs prescribed were angiotensin converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARB) in 61.5%, beta blockers in 49.8%, dihydropyridine calcium channel blockers (CCB) in 46.8%, ARB in 44.4%, diuretics in 32.1% ACEi in 13.4%, other CCBs in 2.6% and mineralocorticoid receptor antagonists (MRA) in 1.1%. One antihypertensive drug was prescribed in 27.4%, two in 41.2%, three in 18.6% and four or more in 5.4%. Prevalence of resistant hypertension using standard definition was 19.4% (95% confidence interval, CI, 18.0-20.8%). It was more in women (23.5%) vs men (15.7%) (p0.001). Using the alternate definition the prevalence was 6.3% (95% CI 5.3-7.0%) and also more in women (6.9%) vs men (5.4%). Resistant hypertension was more common in patients60 years (odds ratio 1.36, 95% CI 1.18-1.58) and women (odds ratio 1.64, 95% CI 1.37-1.97).Prevalence of resistant hypertension is high in a secondary-care practice in India. It is significantly greater among older patients and women.

As tool compounds to study cardiac ischemia, the endogenous δ-opioid receptors (δOR) agonist Leu5-enkephalin and the more metabolically stable synthetic peptide (d-Ala2, d-Leu5)-enkephalin are frequently employed. However, both peptides have similar pharmacological profiles that restrict detailed investigation of the cellular mechanism of the δOR’s protective role during ischemic events. Thus, a need remains for δOR peptides with improved selectivity and unique signaling properties for investigating the specific roles for δOR signaling in cardiac ischemia. To this end, we explored substitution at the Phe4 position of Leu5-enkephalin for its ability to modulate receptor function and selectivity. Peptides were assessed for their affinity to bind to δORs and µ-opioid receptors (µORs) and potency to inhibit cAMP signaling and to recruit β-arrestin 2. Additionally, peptide stability was measured in rat plasma. Substitution of the meta-position of Phe4 of Leu5-enkephalin provided high-affinity ligands with varying levels of selectivity and bias at both the δOR and µOR and improved peptide stability, while substitution with picoline derivatives produced lower-affinity ligands with G protein biases at both receptors. Overall, these favorable substitutions at the meta-position of Phe4 may be combined with other modifications to Leu5-enkephalin to deliver improved agonists with finely tuned potency, selectivity, bias and drug-like properties.

As tool compounds to study cardiac ischemia, the endogenous &delta, opioid receptors (&delta, OR) agonist Leu5-enkephalin and the more metabolically stable synthetic peptide (d-Ala2, d-Leu5)-enkephalin are frequently employed. However, both peptides have similar pharmacological profiles that restrict detailed investigation of the cellular mechanism of the &delta, OR&rsquo, s protective role during ischemic events. Thus, a need remains for &delta, OR peptides with improved selectivity and unique signaling properties for investigating the specific roles for &delta, OR signaling in cardiac ischemia. To this end, we explored substitution at the Phe4 position of Leu5-enkephalin for its ability to modulate receptor function and selectivity. Peptides were assessed for their affinity to bind to &delta, ORs and &micro, opioid receptors (&micro, ORs) and potency to inhibit cAMP signaling and to recruit &beta, arrestin 2. Additionally, peptide stability was measured in rat plasma. Substitution of the meta-position of Phe4 of Leu5-enkephalin provided high-affinity ligands with varying levels of selectivity and bias at both the &delta, OR and &micro, OR and improved peptide stability, while substitution with picoline derivatives produced lower-affinity ligands with G protein biases at both receptors. Overall, these favorable substitutions at the meta-position of Phe4 may be combined with other modifications to Leu5-enkephalin to deliver improved agonists with finely tuned potency, selectivity, bias and drug-like properties.

Phenylpropanoids and their derivatives are plant secondary metabolites widely present in fruits, vegetables, cereal grains, beverages, spices and herbs. They are known to have multifaceted effects which include antimicrobial, antioxidant, anti-inflammatory, antidiabetic, anticancer activities and as well as exhibits renoprotective, neuroprotective, cardioprotective and hepatoprotective effects. Owing to their antioxidant, antimicrobial and photoprotective properties, these compounds have wide application in the food (preservation, packaging films and edible coating), pharmaceutical, cosmetic and other industries such as textile (colorant), biofuel (antioxidant additive) and sensors (sensing biologically relevant molecules). Phenylpropanoids are present in commercially available dietary supplements and skin care products. In this review, we have presented the current knowledge on the biosynthesis, occurrence, biological activities of phenylpropanoids and their derivatives, along with the mechanism of action and their potential applications in various industries.

Renin-angiotensin system (RAS) blockers (angiotensin converting enzyme inhibitors ACEI, angiotensin receptor blockers, ARB) are preferred drugs to control hypertension among diabetic patients. To determine frequency of RAS blocker use in hypertensive patients with type 2 diabetes, we performed a multisite study in India.We evaluated physician prescriptions in consecutive patients with type 2 diabetes at 9 sites in India. Details of socio-demographic characteristics, clinical findings and prescription medicines were obtained. Descriptive statistics are reported.Hypertension treatment details were available in 8056 of 8699 diabetic patients (4829 men, 3227 women). No hypertension was in 3300 (40.9%), hypertension in 3625 (45.0%), and hypertension with vascular disease in 1131 (14.0%). In diabetics with no hypertension, hypertension, and hypertension with vascular disease, respectively, prescriptions of antihypertensive drugs was: RAS blockers in 19.4, 48.2 and 58.1%, beta-blockers in 4.8, 31.6 and 38.8%, calcium channel blockers in 0.4, 27.4 and 14.3% and diuretics in 0.6, 36.4 and 17.1%. ACEIs were prescribed more frequently than ARB's in hypertensive diabetics (60.7 vs 39.2%) as well as in diabetics with vascular disease (58.6 vs 41.4%). In diabetics with hypertension (n=3625) prescription of one, two or three antihypertensive drugs was 49.8%, 33.7% and 3.5% while statins were prescribed in 54.1%.Use of RAS blockers (ACEI or ARB) in uncomplicated as well as complicated hypertensive patients with type 2 diabetes is sub-optimal. Most of the patients are on one drug and prescription of ≥3 drugs are rare. Statins are prescribed in only a half.

Although, Karanj (Pongamia glabra) cake is an important proteinaceous feed resource for livestock but the presence of toxic principles such as karanjin, pongamol and trypsin inhibitors in raw solvent extracted karanj cake restricts its comprehensive use as safe animal feed resources. In the present investigation solvent extracted raw karanj cake was subjected to in vitro studies by incorporation in the concentrate mixture at four graded levels replacing soy bean meal on protein equivalent basis (25, 50, 75 and 100%) in order to understand the rumen fermentation pattern. The inclusion of graded levels of solvent extracted raw karanj cake in the concentrate mixture replacing protein in SBM even at 100% resulted no significant difference in rumen in vitro fermentation pattern in terms of substrate degradation and gas volume produced in 24 h, truly degradable organic matter in rumen (TDOMR; mg/ 200mg), TDOMR%, microbial biomass production (MBP; mg/200mg), efficiency of microbial biomass production (MBP/100mg TDOMR) and partitioning factor (PF).

Synthetic dyes are toxic and carcinogenic in nature, which also causes environmental pollution. The present study was aimed to decolorize various commercial dyes using purified recombinant bacterial laccases. Laccase gene from Yersinia enterocolitica strain 8081 (yacK), Y. enterocolitica strain 7 (yacK) and Bacillus pumilus DSKK1 was cloned in vector pET28a and overproduced in host Escherichia coli BL21. The high yield of recombinant laccase protein resulted in the formation of inclusion bodies, which were further solubilized, refolded, and purified. The purified recombinant laccases were alkali-tolerant and thermostable, with pH optima at 7–8, temperature optima at 60–70 °C and low redox potential. For in silico studies, laccase protein models of B. pumilus DSKK1, Y. enterocolitica strain 7 and Y. enterocolitica strain 8081 were docked with commercial dyes. This is the first and foremost study where the stability of docked complexes of pathogenic and non-pathogenic microorganism has been explored via molecular dynamics (MD) simulations using Gromacs version 4.5.5 with the gromos96 43a force field. Finally, the in silico results were validated experimentally and it was found that purified laccases from B. pumilus DSKK1 and Y. enterocolitica strain 7 efficiently decolorized rose bengal (90.4%), malachite green (77.7%), and congo red (74.5%) dyes.

The inhibition of amyloid-β (Aβ) aggregation is a promising approach towards therapeutic intervention for Alzheimer’s disease (AD). Thirty eight tetrapeptides based upon Aβ39-42 C-terminus fragment of the parent Aβ peptide were synthesized. The sequential replacement/modification employing unnatural amino acids imparted scaffold diversity, augmented activity, enhanced blood brain barrier permeability and offered proteolytic stability to the synthetic peptides. Several peptides exhibited promising protection against Aβ aggregation-mediated-neurotoxicity in PC-12 cells at doses ranged between 10 μM and 0.1 μM, further confirmed by the thioflavin-T fluorescence assay. CD study illustrate that these peptides restrict the β-sheet formation, and the non-appearance of Aβ42 fibrillar structures in the electron microscopy confirm the inhibition of Aβ42 aggregation. HRMS and ANS fluorescence spectroscopic analysis provided additional mechanistic insights. Two selected lead peptides 5 and 16 depicted enhanced blood-brain penetration and stability against serum and proteolytic enzyme. Structural insights into ligand-Aβ interactions on the monomeric and proto-fibrillar units of Aβ were computationally studied. Promising inhibitory potential and short sequence of the lead peptides offers new avenues for the advancement of peptide-derived therapeutics for AD.

Thyrotropin-Releasing Hormone (TRH), a tripeptide amide with molecular formula L-pGlu-L-His-L- Pro-NH2, is used in the treatment of brain/spinal injury and certain central nervous system (CNS) disorders, including schizophrenia, Alzheimer's disease, epilepsy, depression, shock and ischemia due to its profound effects on the CNS. However, TRH's therapeutic activity is severely hampered because of instability and hydrophilicity owing to its peptidic nature which results into ineffective penetration into the blood brain barrier. In the present study, we report the synthesis and stability studies of novel chitosan engineered TRH encapsulated poly(lactide-co-glycolide) (PLGA) based nanoformulation. The aim of such an encapsulation is to allow effective delivery of TRH in biological systems as the peptidase degrade naked TRH. The synthesis of TRH was carried out manually in solution phase followed by its encapsulation using PLGA to form polymeric nanoparticles (NPs) via nanoprecipitation technique. Different parameters such as type of organic phase, concentration of stabilizer, ratio of organic phase and aqueous phase, rate of addition of organic phase were optimized, tested and evaluated for particle size, encapsulation efficiency, and stability of NPs. The TRH-PLGA NPs were then surface modified with chitosan to achieve positive surface charge rendering them potential membrane penetrating agents. PLGA, PLGA-TRH, Chitosan-PLGA and Chitosan-PLGA-TRH NPs were characterized and analyzed using Dynamic Light Scattering (DLS), Transmissiom Electron Microscopy (TEM) and Infra-red spectroscopic techniques.

Sixty fungal cultures were isolated from agricultural soil, industrial soil, forest canopy soil having decomposed leaf litter and compost samples collected from different regions of India. Fifteen fungal cultures were selected qualitatively for the production of xylanase and cellulases and were identified employing ITS, NS and MNS primers. The enzyme cocktail consisting of 3811 IU g(-1) of xylanase and 9.9 IU g(-1) of cellulase from Trichoderma longibrachiatum MDU-6 was selected quantitatively for the deinking of diverse paper wastes. The enzyme production increased two fold when produced at tray level in comparison with flasks. The enzyme cocktail was effective in the deinking of old newspaper samples with significant removal of chromophores, phenolics and hydrophobic compounds and less sugar loss. While in case of examination papers and laser printed papers, ink removal was not very significant. Moreover, the sugar loss was significantly high in case of examination papers. The deinking results were further confirmed with FTIR analysis. Deinked newspaper pulp sample shows brightness of 52%, which was 9.6% high than its control sample. The ERIC value for deinked newspaper pulp was found to be 655.9 ppm. Thereafter, the deinked newspaper pulp was examined under light microscope after differential staining with safranin and malachite green and also examined under scanning and transmission electron microscope, which revealed fibrillation and perforation.

Due to the negative health and environmental consequences of fossil fuels, lignocellulosic ethanol has garnered a great interest as a clean and potent renewable energy resource. The presence of excess amount of water hinders the application of ethanol produced, necessitating the implication of robust recovery and purification techniques. Typically, ethanol recovery starts with a conventional distillation process yielding azeotropic ethanol. Further, dehydration and purification steps are employed to achieve fuel-grade ethanol, which consumes tremendous amount of energy and incur high operational cost; eventually limits the economic feasibility of lignocellulosic ethanol on commercial scale. Therefore, to overcome such obstacles, the synergetic application of distillation or adsorption with membrane-mediated processes seems to be a promising approach in terms of energy conservation, cost-effectiveness, and environmental security. In this review article, we have made an appraisal of the past and current purification and recovery technologies for first generation ethanol, which can be a learning trend for the recovery of lignocellulosic ethanol from the fermented broth, with desired purity.