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Aim: Depression is common in Type 2 diabetes, yet rates vary. Overlap between symptoms of depression and diabetes may account for this variability in depression prevalence rates. We examined to what extent depression prevalence was a function of the proportion of depression–diabetes symptom overlap (items within symptom dimensions) and sample characteristics. Methods: Electronic and hand searching of published and unpublished works identified 147 eligible papers. Of 3656 screened, 147 studies (149 samples, N = 17–229 047, mean sample age 25.4–82.8 years, with 152 prevalence estimates), using 24 validated depression questionnaires were selected. Sample size, publication type, sample type, gender, age, BMI, HbA1c, depression questionnaire and prevalence rates were extracted. Results: Prevalence rates ranged from 1.8% to 88% (mean = 28.30%) and were higher in younger samples, samples with higher mean HbA1c and clinic samples. Diabetes–depression symptom overlap did not affect prevalence. A higher proportion of anhedonia, cognition, cognitive, negative affect and sleep disturbance symptoms, and a lower proportion of somatic symptoms were consistently associated with higher depression prevalence. Conclusions: The lack of an overall effect of diabetes–depression symptom overlap might suggest that assessment of depression in Type 2 diabetes is generally not confounded by co‐occuring symptoms. However, questionnaires with proportionally more or fewer items measuring other symptom categories were associated with higher estimates of depression prevalence. Depression measures that focus on the cardinal symptoms of depression (e.g. negative affect and cognition), limiting symptoms associated with increasing diabetes symptomatology (e.g. sleep disturbance, cognitive) may most accurately diagnose depression. What's new?: Prevalence of depression ranged from 1.8% to 88% (mean = 28.30%) across 147 studies. Younger sample age, higher HbA1c and clinic samples were associated with higher depression prevalence. There was no effect of depression–diabetes overlap items on depression estimates.Questionnaires with a higher proportion of anhedonia, cognition, cognitive, negative affect and sleep disturbance symptoms, and a lower proportion of somatic symptoms were consistently associated with higher depression prevalence.Depression measures that focus on the cardinal symptoms of depression (e.g. negative affect and cognition), limiting symptoms associated with increased diabetes symptomatology (e.g. sleep disturbance, cognitive) may most accurately diagnose depression. [ABSTRACT FROM AUTHOR]

To address large gaps in our understanding of the molecular regulation of articular and growth plate cartilage development in humans, we used our directed differentiation approach to generate these distinct cartilage tissues from human embryonic stem cells. The resulting transcriptomic profiles of hESC-derived articular and growth plate chondrocytes were similar to fetal epiphyseal and growth plate chondrocytes, with respect to genes both known and previously unknown to cartilage biology. With the goal to characterize the regulatory landscapes accompanying these respective transcriptomes, we mapped chromatin accessibility in hESC-derived chondrocyte lineages, and mouse embryonic chondrocytes, using ATAC-sequencing. Integration of the expression dataset with the differentially accessible genomic regions revealed lineage-specific gene regulatory networks. We validated functional interactions of two transcription factors (TFs) (RUNX2 in growth plate chondrocytes and RELA in articular chondrocytes) with their predicted genomic targets. The maps we provide thus represent a framework for probing regulatory interactions governing chondrocyte differentiation. This work constitutes a substantial step towards comprehensive and comparative molecular characterizations of distinct chondrogenic lineages and sheds new light on human cartilage development and biology.

While many genetic loci have been found to be associated with disease, not many have had their causal variants and mechanisms investigated. Here, the authors experimentally dissect two loci near GDF5 which are associated with two different joint disorders and which map to independent regulatory elements.

Summary: The angiotensin-converting enzyme 2 (ACE2) protein is a key catalytic regulator of the renin-angiotensin system (RAS), involved in fluid homeostasis and blood pressure modulation. ACE2 also serves as a cell-surface receptor for some coronaviruses such as SARS-CoV and SARS-CoV-2. Improved characterization of ACE2 regulation may help us understand the effects of pre-existing conditions on COVID-19 incidence, as well as pathogenic dysregulation following viral infection. Here, we perform bioinformatic analyses to hypothesize on ACE2 gene regulation in two different physiological contexts, identifying putative regulatory elements of ACE2 expression. We perform functional validation of our computational predictions via targeted CRISPR-Cas9 deletions of these elements in vitro, finding them responsive to immune signaling and oxidative-stress pathways. This contributes to our understanding of ACE2 gene regulation at baseline and immune challenge. Our work supports pursuit of these putative mechanisms in our understanding of infection/disease caused by current, and future, SARS-related viruses such as SARS-CoV-2.

Aim: The present study tested a compensatory executive intervention for prospective memory (goal management training) for the first time in older adults. Prospective memory (the ability to remember and execute a task in the future) declines with age, with significant implications for older adults' activities of daily living and quality of life. Prospective memory interventions have focused primarily on the retrospective component of prospective memory (e.g., implementation intentions). However, executive dysfunction is also implicated in age-related prospective memory decline. Methods: Community-dwelling older adults were randomly allocated to receive goal management training, implementation intentions or no intervention. Prospective memory was assessed before and after the intervention with a well-validated laboratory-based prospective memory measure.  Results: Contrary to predictions, neither goal management training nor implementation intentions were successful at improving prospective memory in healthy older adults. Participants who received goal management training were more likely to have difficulty comprehending the intervention. Post-hoc analyses suggested implementation intentions improved prospective memory specifically for participants with poorer baseline prospective memory.  Conclusions: These results represent important cautionary findings about the possible limitations of goal management training to improve prospective memory in older adults. Future research should also consider the role of baseline prospective memory ability in affecting response to compensatory intervention.

Objective: Intraindividual variability (IIV)-variance in an individual's cognitive performance-may be associated with subsequent cognitive decline and/or conversion to dementia in older adults. This novel measure of cognition encompasses two main operationalizations: inconsistency (IIV-I) and dispersion (IIV-D), referring to variance within or across tasks, respectively. Each operationalization can also be measured with or without covariates. This meta-analytic study explores the association between IIV and subsequent cognitive outcomes regardless of operational definition and measurement approach., Method: Longitudinal studies ( N = 13) that have examined IIV in association with later cognitive decline and/or conversation to MCI/dementia were analyzed. The effect of IIV operationalization was explored. Additional subgroup analysis of measurement approaches could not be examined due to the limited number of appropriate studies available for inclusion., Results: Meta-analytic estimates suggest IIV is associated with subsequent cognitive decline and/or conversion to MCI/dementia ( r = .20, 95% CI [.09, .31]) with no significant difference between the two operationalisations observed ( Q = 3.41, p = .065)., Conclusion: Cognitive IIV, including both IIV-I and IIV-D operationalizations, appears to be associated with subsequent cognitive decline and/or dementia and may offer a novel indicator of incipient dementia in both clinical and research settings. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Study Objectives: To determine cognitive profiles in individuals with short sleep duration insomnia (SSDI) and normal sleep duration insomnia (NSDI; also, paradoxical insomnia), compared to healthy sleepers. Method: Polysomnographic (PSG) and neuropsychological data were analysed from 902 community-based Raine Study participants aged 22 ± 0.6 years of whom 124 met criteria for insomnia (53 with NSDI and 71 with or SSDI) and 246 were classified as healthy with normal sleep (i.e., without insomnia or other sleep disorders). Measurements of self- report (attention and memory) and laboratory-assessed (attention, episodic memory, working memory, learning, and psychomotor function) cognition and mood, and PSG-based sleep stages (% total sleep time; %TST) were compared between these 3 groups. Results: In comparison to the healthy sleeper group, both insomnia groups had poorer self-reported attention, memory, mood, and sleep, and poorer laboratory-assessed attention (inconsistency). The NSDI group had less consistent working memory reaction time than healthy-sleepers or those with SSDI. The SSDI group had more inconsistency in executive function (shifting), and showed greater %TST in stage N1 and N3, and less REM sleep than either healthy-sleepers or those with NSDI. Conclusions: Individuals with NSDI demonstrated greater working memory inconsistency, despite no laboratory assessed sleep problems, implicating early signs of pathophysiology other than disturbed sleep. Those with SSDI demonstrated different sleep architecture, poorer attention (inconsistency), and greater executive function (inconsistency) compared to healthy-sleepers and those with NSDI, implicating sleep disturbance in the disease process of this phenotype., 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 © 2021 Olaithe, Ree, McArdle, Donaldson, Pushpanathan, Eastwood and Bucks.)

Study Objectives: Although cognitive dysfunction is a recognized consequence of untreated obstructive sleep apnea (OSA), the deficit pattern is heterogeneous. Understanding this heterogeneity may identify those at risk of cognitive deficits and guide intervention strategies. To facilitate understanding, we examined whether distinct profiles of neuropsychological performance were present in OSA and, if so, how they are related to other OSA features., Methods: We studied sleep clinic (n = 121) and community (n = 398) samples with moderate-severe OSA (apnea-hypopnea index ≥ 15 events/h). Attention and memory were assessed using the Cognitive Drug Research system. Sleep was assessed using polysomnography in the clinic sample and dual channel (flow, oximetry) portable monitoring in the community sample. Latent profile analysis was used to determine structure of cognitive clusters. Discriminant function analysis was used to examine associations between nocturnal and diurnal features of OSA and profile membership., Results: Both samples were best characterized by a 3-profile solution: (1) strong thinkers (performed well across most domains and showed greater cognitive reserve); (2) inattentive fast thinkers (strong processing speed but poor ability to maintain attention); and (3) accurate slow thinkers (strengths in maintaining attention but poor processing speed). Profile membership was associated with mean overnight oxygen saturation and cognitive reserve in the clinic sample and the presence of cardiovascular disease and/or diabetes in the community sample., Conclusions: These findings help explain the diversity of outcomes in previous studies of cognitive dysfunction in OSA by demonstrating that individual differences in cognitive reserve, nocturnal oxygen saturation, and comorbidities affect how cognition is impacted by OSA., (© 2020 American Academy of Sleep Medicine.)

Accelerating growth and global expansion of antimicrobial resistance has deepened the need for discovery of novel antimicrobial agents. Antimicrobial peptides have clear advantages over conventional antibiotics which include slower emergence of resistance, broad-spectrum antibiofilm activity, and the ability to favourably modulate the host immune response. Broad bacterial susceptibility to antimicrobial peptides offers an additional tool to expand knowledge about the evolution of antimicrobial resistance. Structural and functional limitations, combined with a stricter regulatory environment, have hampered the clinical translation of antimicrobial peptides as potential therapeutic agents. Existing computational and experimental tools attempt to ease the preclinical and clinical development of antimicrobial peptides as novel therapeutics. This Review identifies the benefits, challenges, and opportunities of using antimicrobial peptides against multidrug-resistant pathogens, highlights advances in the deployment of novel promising antimicrobial peptides, and underlines the needs and priorities in designing focused development strategies taking into account the most advanced tools available., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Objective: Provide updated older adult (ages 60+) normative data for the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), Form A, using regression techniques, and corrected for education, age, and gender., Method: Participants (aged 60-93 years; N = 415) were recruited through the Healthy Ageing Research Program (HARP), University of Western Australia, and completed Form A of the RBANS as part of a wider neuropsychological test battery. Regression-based techniques were used to generate normative data rather than means-based methods. This methodology allows for the control of demographic variables using continuous data. To develop norms, the data were assessed for: (1) normality; (2) associations between each subtest score and age, education, and gender; (3) the effect of age, education, and gender on subtest scores; and (4) residual scores which were converted to percentile distributions., Results: Differences were noted between the three samples, some of which were small and may not represent a clinically meaningful difference. Younger age, more years of education, and female gender were associated with better scores on most subtests. Frequency distributions, means, and standard deviations were produced using unstandardized residual scores to remove the effects of age, education, and gender., Conclusions: These normative data expand upon past work by using regression-based techniques to generate norms, presenting percentiles, as well as means and standard deviations, correcting for the effect of gender, and providing a free-to-use Excel macro to calculate percentiles., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: Despite its brevity and face validity, little is known about the construct validity of the naturalistic "Key Task" of prospective memory (PM), in which an examinee is instructed to remind the examiner at a designated time to retrieve keys (or another belonging) placed out of sight., Method: Study 1 included 162 HIV+ and 52 HIV- comparison participants who completed the Key Task alongside well-validated measures of PM and a comprehensive neuropsychological battery that included everyday functioning measures. Study 2 used broadly parallel methods in 168 older community-dwelling Australians., Results: Overall, the Key Task was not reliably associated with neurocognitive functioning (including clinical and experimental measures of PM), PM symptoms, or everyday functioning in either sample., Conclusions: The Key Task did not demonstrate compelling evidence of construct validity among persons living with HIV disease or older adults, which raises doubts regarding its clinical usefulness as a measure of PM., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Organophosphates are the most frequently and largely applied insecticide in the world due to their biodegradable nature. Gut microbes were shown to degrade organophosphates and cause intestinal dysfunction. The diabetogenic nature of organophosphates was recently reported but the underlying molecular mechanism is unclear. We aimed to understand the role of gut microbiota in organophosphate-induced hyperglycemia and to unravel the molecular mechanism behind this process., Results: Here we demonstrate a high prevalence of diabetes among people directly exposed to organophosphates in rural India (n = 3080). Correlation and linear regression analysis reveal a strong association between plasma organophosphate residues and HbA1c but no association with acetylcholine esterase was noticed. Chronic treatment of mice with organophosphate for 180 days confirms the induction of glucose intolerance with no significant change in acetylcholine esterase. Further fecal transplantation and culture transplantation experiments confirm the involvement of gut microbiota in organophosphate-induced glucose intolerance. Intestinal metatranscriptomic and host metabolomic analyses reveal that gut microbial organophosphate degradation produces short chain fatty acids like acetic acid, which induces gluconeogenesis and thereby accounts for glucose intolerance. Plasma organophosphate residues are positively correlated with fecal esterase activity and acetate level of human diabetes., Conclusion: Collectively, our results implicate gluconeogenesis as the key mechanism behind organophosphate-induced hyperglycemia, mediated by the organophosphate-degrading potential of gut microbiota. This study reveals the gut microbiome-mediated diabetogenic nature of organophosphates and hence that the usage of these insecticides should be reconsidered.

Study Objectives: To compare polysomnographic parameters in high altitude (HA) native Andean children with low altitude (LA) native peers in order to explain the nocturnal oxyhemoglobin saturation (SpO2) instability reported in HA native children and to study the effect on sleep quality., Methods: Ninety-eight healthy children aged 7-10 y and 13-16 y were recruited at LA (500 m) or HA (3,650 m) above sea level. Physical examination was undertaken and genetic ancestry determined from salivary DNA to determine proportion of European ancestry, a risk factor for poor HA adaptation. Attended polysomnography was carried out over 1 night for 58 children at their resident location., Results: Of 98 children recruited, 85 met inclusion criteria, 58 of 85 (68.2%) completed polysomnography, of which 56 were adequate for analysis: 30 at LA (17 male) and 26 at HA (16 male). There were no altitude differences in genetic ancestry, but a high proportion of European admixture (median 50.6% LA; 44.0% HA). SpO2 was less stable at HA with mean 3% and 4% oxygen desaturation indices greater (both P < 0.001) than at LA. This was not explained by periodic breathing. However, more obstructive hypopnea was observed at HA (P < 0.001), along with a trend toward more central apnea (P = 0.053); neither was explained by clinical findings. There was no difference in sleep quality between altitudes., Conclusions: HA native Andean children have more respiratory events when scoring relies on SpO2 desaturation due to inherent SpO2 instability. Use of American Academy of Sleep Medicine scoring criteria may yield false-positive results for obstructive sleep-disordered breathing at HA., (© 2016 Associated Professional Sleep Societies, LLC.)

A growing issue of pathogen resistance to antibiotics has fostered the development of innovative approaches for novel drug development. Here, we report the physicochemical and biological properties of an antifungal peptide, MMGP1, based on computational analysis. Computation of physicochemical properties has revealed that the natural biological activities of MMGP1 are coordinated by its intrinsic properties such as net positive charge (+5.04), amphipathicity, high hydrophobicity, low hydrophobic moment, and higher isoelectric point (11.915). Prediction of aggregation hot spots in MMGP1 had revealed the presence of potentially aggregation-prone segments that can nucleate in vivo aggregation (on the membrane), whereas no aggregating regions were predicted for in vitro aggregation (in solutions) of MMGP1. This ability of MMGP1 to form oligomeric aggregates on membrane further substantiates its direct-cell penetrating potency. Monte Carlo simulation of the interactions of MMGP1 in the aqueous phase and different membrane environments revealed that increasing the proportion of acidic lipids on membrane had led to increase in the peptide helicity. Furthermore, the peptide adopts energetically favorable transmembrane configuration, by inserting peptide loop and helix termini into the membrane containing >60% of anionic lipids. The charged lipid-based insertion of MMGP1 into membrane might be responsible for the selectivity of peptide toward fungal cells. Additionally, MMGP1 possessed DNA-binding property. Computational docking has identified DNA-binding residues (TRP3, SER4, MET7, ARG8, PHE10, ALA11, GLY20, THR21, ARG22, MET23, TRP34, and LYS36) in MMGP1 crucial for its DNA-binding property. Furthermore, computational mutation analysis revealed that aromatic amino acids are crucial for in vivo aggregation, membrane insertion, and DNA-binding property of MMGP1. These data provide new insight into the molecular determinants of MMGP1 antifungal activity and also serves as the template for the design of novel peptide antibiotics.

Termite gut and termite nest possess complex microbial communities. However, only limited information is available on the comparative investigation of termite gut- and nest-associated microbial communities. In the present study, we examined and compared the bacterial diversity of termite gut and their respective nest by high-throughput sequencing of V3 hypervariable region of 16S rDNA. A total of 14 barcoded libraries were generated from seven termite gut samples and their respective nest samples, and sequenced using Ion Torrent platform. The sequences of each group were pooled, which yielded 170,644 and 132,000 reads from termite gut and termite nest samples, respectively. Phylogenetic analysis revealed significant differences in the bacterial diversity and community structure between termite gut and termite nest samples. Phyla Verrucomicrobia and Acidobacteria were observed only in termite gut, whereas Synergistetes and Chlorobi were observed only in termite nest samples. These variations in microbial structure and composition could be attributed with the differences in physiological conditions prevailing in the termite gut (anoxic and alkaline) and termite nest (oxic, slightly acidic and rich in organic matter) environment. Overall, this study unmasked the complexity of bacterial population in the respective niche. Interestingly, majority of the sequence reads could be classified only up to the domain level indicating the presence of a huge number of uncultivable or unidentified novel bacterial species in both termite gut and nest samples. Whole metagenome sequencing and assessing the metabolic potential of these samples will be useful for biotechnological applications.

Streptococcus agalactiae infection causes high mortality in cardiovascular disease (CVD) patients, especially in case of setting prosthetic valve during cardiac surgery. However, the pathogenesis mechanism of S. agalactiae associate with CVD has not been well studied. Here, we have demonstrated the pathogenicity of S. agalactiae in rat cardiomyocytes (H9C2). Interestingly, both live and dead cells of S. agalactiae were uptaken by H9C2 cells. To further dissect the process of S. agalactiae internalization, we chemically inhibited discrete parts of cellular uptake system in H9C2 cells using genistein, chlorpromazine, nocodazole and cytochalasin B. Chemical inhibition of microtubule and actin formation by nocodazole and cytochalasin B impaired S. agalactiae internalization into H9C2 cells. Consistently, reverse‒ transcription PCR (RT‒PCR) and quantitative real time‒PCR (RT-qPCR) analyses also detected higher levels of transcripts for cytoskeleton forming genes, Acta1 and Tubb5 in S. agalactiae‒infected H9C2 cells, suggesting the requirement of functional cytoskeleton in pathogenesis. Host survival assay demonstrated that S. agalactiae internalization induced cytotoxicity in H9C2 cells. S. agalactiae cells grown with benzyl penicillin reduced its ability to internalize and induce cytotoxicity in H9C2 cells, which could be attributed with the removal of surface lipoteichoic acid (LTA) from S. agalactiae. Further, the LTA extracted from S. agalactiae also exhibited dose‒dependent cytotoxicity in H9C2 cells. Taken together, our data suggest that S. agalactiae cells internalized H9C2 cells through energy‒dependent endocytic processes and the LTA of S. agalactiae play major role in host cell internalization and cytotoxicity induction.

Bacterial infections in myocardium may lead to the myocardial damage, which may progress to dilated cardiomyopathy and cardiac arrest. Pseudomonas aeruginosa has been reported to cause myocarditis and other systemic infections especially in immunocompromised patients. To understand the cellular responses during the establishment of infection in myocardium, we challenged differentiated H9C2 cells with P. aeruginosa PAO1. We also did comparison studies with infected undifferentiated form of H9C2 cells. Invasion studies revealed that PAO1 can invade both forms of cells and is able to survive and replicate within the host. Internalization of PAO1 was confirmed by live cell imaging and flow cytometry analysis. Though invasion of the pathogen triggered an increased ROS production in the host cells at earlier post-infection periods, it was decreased at later post-infection periods. Invasion of PAO1 induced cell death through apoptosis in differentiated H9C2 cells. Significant decrease in cell size, formation of polarized mitochondria, and nuclear fragmentation were observed in the infected differentiated cells. On the contrary, cell death preceded by multinucleation was observed in infected undifferentiated H9C2 cells. Morphological markers such as multinuclei and micro nuclei were observed. Cell cycle arrest in G2/M phase corroborates that the undifferentiated H9C2 cells experienced cell death preceded by multinucleation., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Lactobacillus fermentum is a lactic acid bacterium of probiotic importance, which is found ubiquitously in fermented milk products. Bile salt hydrolase (BSH) has a significant role in affording probiotic properties to lactobacilli. In the present study, two bsh genes encoding BSH1 and BSH2 were identified from the draft genome sequence of L. fermentum MTCC 8711. Nucleotide comparison revealed no significant similarity between bsh1 and bsh2 genes, whereas the deduced amino acid sequences showed 26 % sequence similarity between both BSH1 and BSH2. Pfam analysis revealed the presence of cys-2 active site residues in the catalytic pocket of both BSH1 and BSH2 highly essential for catalysis. Phylogentic analysis of BSH1 and BSH2 revealed the possible independent origin of these proteins in Lactobacillus. We cloned these genes in pSLp111.3, a Lactobacillus expression vector with signal peptide A (slpA) and expressed in the native L. fermentum strain for overexpression and extracellular secretion. The bsh1 gene failed to express and to produce promising BSH activity. However, bsh2 gene was overexpressed and the recombinant strain showed improved BSH activity. Induction of the recombinant strain with an optimal 2 % xylose concentration secreted 0.5 U/ml of the BSH into extracellular medium. Furthermore, the recombinant strain was able to completely assimilate the 100-μg/ml cholesterol within 24 h, whereas the native strain took 72 h for the complete assimilation of cholesterol.

Cardiovascular diseases (CVDs) are the leading cause of death worldwide. An expanding body of evidence supports the role of human microbiome in the establishment of CVDs and, this has gained much attention recently. This work was aimed to study the circulating human microbiome in CVD patients and healthy subjects. The levels of circulating cell free DNA (circDNA) was higher in CVD patients (n = 80) than in healthy controls (n = 40). More specifically, the relative levels of circulating bacterial DNA and the ratio of 16S rRNA/β-globin gene copy numbers were higher in the circulation of CVD patients than healthy individuals. In addition, we found a higher circulating microbial diversity in CVD patients (n = 3) in comparison to healthy individuals (n = 3) by deep shotgun sequencing. At the phylum level, we observed a dominance of Actinobacteria in CVD patients, followed by Proteobacteria, in contrast to that in healthy controls, where Proteobacteria was predominantly enriched, followed by Actinobacteria. The circulating virome in CVD patients was enriched with bacteriophages with a preponderance of Propionibacterium phages, followed by Pseudomonas phages and Rhizobium phages in contrast to that in healthy individuals, where a relatively greater abundance of eukaryotic viruses dominated by Lymphocystis virus (LCV) and Torque Teno viruses (TTV) was observed. Thus, the release of bacterial and viral DNA elements in the circulation could play a major role leading to elevated circDNA levels in CVD patients. The increased circDNA levels could be either the cause or consequence of CVD incidence, which needs to be explored further.

Lactobacillus fermentum strain MTCC 8711 is a lactic acid bacterium isolated from yogurt. Here, we describe the draft genome sequence and annotation of this strain. The 2,566,297-bp-long genome consisted of a single chromosome and seven plasmids. The genome contains 2,609 protein-coding and 74 RNA genes.

Background: Development of resistant variants to existing antifungal drugs continues to be the serious problem in Candida albicans-induced fungal pathogenesis, which has a considerable impact on animal and human health. Identification and characterization of newer drugs against C. albicans is, therefore, essential. MMGP1 is a direct cell-penetrating peptide recently identified from marine metagenome, which was found to possess potent antifungal activity against C. albicans., Methodology/principal Findings: In this study, we investigated the mechanism of antifungal action of MMGP1 against C. albicans. Agarose gel shift assay found the peptide to be having a remarkable DNA-binding ability. The modification of the absorption spectra and fluorescence quenching of the tryptophyl residue correspond to the stacking between indole ring and nucleotide bases. The formation of peptide-DNA complexes was confirmed by fluorescence quenching of SYTO 9 probe. The interaction of peptide with plasmid DNA afforded protection of DNA from enzymatic degradation by DNase I. In vitro transcription of mouse β-actin gene in the presence of peptide led to a decrease in the level of mRNA synthesis. The C. albicans treated with MMGP1 showed strong inhibition of biosynthetic incorporation of uridine analog 5-ethynyluridine (EU) into nascent RNA, suggesting the peptide's role in the inhibition of macromolecular synthesis. Furthermore, the peptide also induces endogenous accumulation of reactive oxygen species (ROS) in C. albicans. MMGP1 supplemented with glutathione showed an increased viability of C. albicans cells. The hyper-produced ROS by MMGP1 leads to increased levels of protein carbonyls and thiobarbituric acid reactive substances and it also causes dissipation of mitochondrial membrane potential and DNA fragmentation in C. albicans cells., Conclusion: And Significance: Therefore, the antifungal activity of MMGP1 could be attributed to its binding with DNA, causing inhibition of transcription followed by endogenous production of ROS, which triggers cascade of events that leads to cell death.

Antimicrobial peptides are diverse group of biologically active molecules with multidimensional properties. In recent past, a wide variety of AMPs with diverse structures have been reported from different sources such as plants, animals, mammals, and microorganisms. The presence of unusual amino acids and structural motifs in AMPs confers unique structural properties to the peptide that attribute for their specific mode of action. The ability of these active AMPs to act as multifunctional effector molecules such as signalling molecule, immune modulators, mitogen, antitumor, and contraceptive agent makes it an interesting candidate to study every aspect of their structural and biological properties for prophylactic and therapeutic applications. In addition, easy cloning and recombinant expression of AMPs in heterologous plant host systems provided a pipeline for production of disease resistant transgenic plants. Besides these properties, AMPs were also used as drug delivery vectors to deliver cell impermeable drugs to cell interior. The present review focuses on the diversity and broad spectrum antimicrobial activity of AMPs along with its multidimensional properties that could be exploited for the application of these bioactive peptides as a potential and promising drug candidate in pharmaceutical industries.

A novel antifungal peptide with 36 amino acids was identified by functional screening of a marine metagenomic library. The peptide did not show similarity with any existing antimicrobial peptide sequences in the databank. The108 bp ORF designated as mmgp1 was cloned and expressed in Escherichia coli BL21 (DE3) using pET expression system. Mass spectrometry analysis of the purified recombinant peptide revealed a molecular mass of 5026.9 Da. The purified recombinant peptide inhibited the growth of Candida albicans and Aspergillus niger. The peptide was predicted to adopt α- helical conformation with an extended coil containing a ligand binding site for N-acetyl-D-glucosamine. The α- helicity of the peptide was demonstrated by circular dichroism spectroscopy in the presence of chitin or membrane mimicking solvent, trifluoroethanol. The chitin binding property of the peptide was also confirmed by fast performance liquid chromatography.

Microbial diversity of 1,000 m deep pelagic sediment from off Coast of Andaman Sea was analyzed by a culture independent technique, bacterial tag encoded FLX titanium amplicon pyrosequencing. The hypervariable region of small subunit ribosomal rRNA gene covering V6-V9, was amplified from the metagenomic DNA and sequenced. We obtained 19,271 reads, of which 18,206 high quality sequences were subjected to diversity analysis. A total of 305 operational taxonomic units (OTUs) were obtained corresponding to the members of firmicutes, proteobacteria, plantomycetes, actinobacteria, chloroflexi, bacteroidetes, and verucomicrobium. Firmicutes was the predominant phylum, which was largely represented with the family bacillaceae. More than 44 % of sequence reads could not be classified up to the species level and more than 14 % of the reads could not be assigned to any genus. Thus, the data indicates the possibility for the presence of uncultivable or unidentified novel bacterial species. In addition, the community structure identified in this study significantly differs with other reports from marine sediments.

An antifungal peptide, MMGP1, was recently identified from marine metagenome. The mechanism of cellular internalization of this peptide in Candida albicans was studied using fluorescein 5-isothiocynate (Sigma, California, USA) labeling followed by fluorescence microscopy and flow cytometry analyses. The peptide could enter C. albicans cells even at 4 °C, where all energy-dependent transport mechanisms are blocked. In addition, the peptide internalization was not affected by the endocytic inhibitor, sodium azide. The kinetic study has shown that the peptide was initially localized on cell membrane and subsequently internalized into cytosol. The MMGP1 treatment exhibited time-dependent cytotoxicity in C. albicans as evidenced by SYTOX Green (Molecular Probes Inc., Eugene, Oreg) uptake., (Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd.)