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1.
Int J Mol Sci ; 25(11)2024 May 26.
Article in English | MEDLINE | ID: mdl-38891970

ABSTRACT

Nowadays, depressive disorder is spreading rapidly all over the world. Therefore, attention to the studies of the pathogenesis of the disease in order to find novel ways of early diagnosis and treatment is increasing among the scientific and medical communities. Special attention is drawn to a biomarker and therapeutic strategy through the microbiota-gut-brain axis. It is known that the symbiotic interactions between the gut microbes and the host can affect mental health. The review analyzes the mechanisms and ways of action of the gut microbiota on the pathophysiology of depression. The possibility of using knowledge about the taxonomic composition and metabolic profile of the microbiota of patients with depression to select gene compositions (metagenomic signature) as biomarkers of the disease is evaluated. The use of in silico technologies (machine learning) for the diagnosis of depression based on the biomarkers of the gut microbiota is given. Alternative approaches to the treatment of depression are being considered by balancing the microbial composition through dietary modifications and the use of additives, namely probiotics, postbiotics (including vesicles) and prebiotics as psychobiotics, and fecal transplantation. The bacterium Faecalibacterium prausnitzii is under consideration as a promising new-generation probiotic and auxiliary diagnostic biomarker of depression. The analysis conducted in this review may be useful for clinical practice and pharmacology.


Subject(s)
Depression , Gastrointestinal Microbiome , Probiotics , Humans , Depression/therapy , Depression/microbiology , Depression/diagnosis , Probiotics/therapeutic use , Biomarkers , Fecal Microbiota Transplantation , Brain-Gut Axis , Prebiotics/administration & dosage
2.
Int J Mol Sci ; 24(22)2023 Nov 17.
Article in English | MEDLINE | ID: mdl-38003647

ABSTRACT

In the last few years, investigation of the gut-brain axis and the connection between the gut microbiota and the human nervous system and mental health has become one of the most popular topics. Correlations between the taxonomic and functional changes in gut microbiota and major depressive disorder have been shown in several studies. Machine learning provides a promising approach to analyze large-scale metagenomic data and identify biomarkers associated with depression. In this work, machine learning algorithms, such as random forest, elastic net, and You Only Look Once (YOLO), were utilized to detect significant features in microbiome samples and classify individuals based on their disorder status. The analysis was conducted on metagenomic data obtained during the study of gut microbiota of healthy people and patients with major depressive disorder. The YOLO method showed the greatest effectiveness in the analysis of the metagenomic samples and confirmed the experimental results on the critical importance of a reduction in the amount of Faecalibacterium prausnitzii for the manifestation of depression. These findings could contribute to a better understanding of the role of the gut microbiota in major depressive disorder and potentially lead the way for novel diagnostic and therapeutic strategies.


Subject(s)
Depressive Disorder, Major , Gastrointestinal Microbiome , Microbiota , Humans , Metagenome
3.
Int J Mol Sci ; 22(17)2021 Aug 26.
Article in English | MEDLINE | ID: mdl-34502130

ABSTRACT

Bifidobacteria are some of the major agents that shaped the immune system of many members of the animal kingdom during their evolution. Over recent years, the question of concrete mechanisms underlying the immunomodulatory properties of bifidobacteria has been addressed in both animal and human studies. A possible candidate for this role has been discovered recently. The PFNA cluster, consisting of five core genes, pkb2, fn3, aaa-atp, duf58, tgm, has been found in all gut-dwelling autochthonous bifidobacterial species of humans. The sensory region of the species-specific serine-threonine protein kinase (PKB2), the transmembrane region of the microbial transglutaminase (TGM), and the type-III fibronectin domain-containing protein (FN3) encoded by the I gene imply that the PFNA cluster might be implicated in the interaction between bacteria and the host immune system. Moreover, the FN3 protein encoded by one of the genes making up the PFNA cluster, contains domains and motifs of cytokine receptors capable of selectively binding TNF-α. The PFNA cluster could play an important role for sensing signals of the immune system. Among the practical implications of this finding is the creation of anti-inflammatory drugs aimed at alleviating cytokine storms, one of the dire consequences resulting from SARS-CoV-2 infection.


Subject(s)
Bacterial Proteins/genetics , Bifidobacterium/physiology , COVID-19/therapy , Protein Serine-Threonine Kinases/genetics , Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , COVID-19/immunology , COVID-19/virology , Cytokine Release Syndrome/immunology , Cytokine Release Syndrome/prevention & control , Cytokines/chemistry , Cytokines/metabolism , Humans , Immune System , Operon/genetics , Protein Serine-Threonine Kinases/chemistry , Protein Serine-Threonine Kinases/metabolism , SARS-CoV-2/isolation & purification
4.
Anaerobe ; 65: 102247, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32771620

ABSTRACT

Most species of the genus Bifidobacterium contain the gene cluster PFNA, which is presumably involved in the species-specific communication between bacteria and their hosts. The gene cluster PFNA consists of five genes including fn3, which codes for a protein containing two fibronectin type III domains. Each fibronectin domain contains sites similar to cytokine-binding sites of human receptors. Based on this finding we assumed that this protein would bind specifically to human cytokines in vitro. We cloned a fragment of the fn3 gene (1503 bp; 501 aa) containing two fibronectin domains, from the strain B. longum subsp. longum GT15. After cloning the fragment into the expression vector pET16b and expressing it in E. coli, the protein product was purified to a homogenous state for further analysis. Using the immunoferment method, we tested the purified fragment's ability to bind the following human cytokines: IL-1ß, IL-6, IL-10, TNFα. We developed a sandwich ELISA system to detect any specific interactions between the purified protein and any of the studied cytokines. We found that the purified protein fragment only binds to TNFα.


Subject(s)
Bacterial Proteins/metabolism , Bifidobacterium/metabolism , Fibronectin Type III Domain , Fibronectins/metabolism , Tumor Necrosis Factor-alpha/metabolism , Bacterial Proteins/chemistry , Bifidobacteriales Infections/metabolism , Bifidobacteriales Infections/microbiology , Bifidobacterium/genetics , Computational Biology/methods , Cytokines/metabolism , Fibronectins/chemistry , Host-Pathogen Interactions , Humans , Multigene Family , Protein Binding , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism
5.
Int J Mol Sci ; 21(23)2020 Dec 03.
Article in English | MEDLINE | ID: mdl-33287416

ABSTRACT

Depression is a global threat to mental health that affects around 264 million people worldwide. Despite the considerable evolution in our understanding of the pathophysiology of depression, no reliable biomarkers that have contributed to objective diagnoses and clinical therapy currently exist. The discovery of the microbiota-gut-brain axis induced scientists to study the role of gut microbiota (GM) in the pathogenesis of depression. Over the last decade, many of studies were conducted in this field. The productions of metabolites and compounds with neuroactive and immunomodulatory properties among mechanisms such as the mediating effects of the GM on the brain, have been identified. This comprehensive review was focused on low molecular weight compounds implicated in depression as potential products of the GM. The other possible mechanisms of GM involvement in depression were presented, as well as changes in the composition of the microbiota of patients with depression. In conclusion, the therapeutic potential of functional foods and psychobiotics in relieving depression were considered. The described biomarkers associated with GM could potentially enhance the diagnostic criteria for depressive disorders in clinical practice and represent a potential future diagnostic tool based on metagenomic technologies for assessing the development of depressive disorders.


Subject(s)
Bacteria/metabolism , Depression/etiology , Depression/metabolism , Gastrointestinal Microbiome , Amino Acids/metabolism , Biomarkers , Brain/metabolism , Depression/psychology , Disease Susceptibility , Energy Metabolism , Functional Food , Humans , Neurotransmitter Agents/metabolism
6.
BMC Microbiol ; 19(1): 160, 2019 07 12.
Article in English | MEDLINE | ID: mdl-31299889

ABSTRACT

BACKGROUND: All living organisms experience physiological changes regulated by endogenous circadian rhythms. The main factor controlling the circadian clock is the duration of daylight. The aim of this research was to identify the impact of various lighting conditions on physiological parameters and gut microbiota composition in rats. 3 groups of outbred rats were subjected to normal light-dark cycles, darkness and constant lighting. RESULTS: After 1 and 3 months we studied urinary catecholamine levels in rats; indicators of lipid peroxidation and antioxidant activity in the blood; protein levels of BMAL1, CLOCK and THRA in the hypothalamus; composition and functional activity of the gut microbiota. Subjecting the rats to conditions promoting desynchronosis for 3 months caused disruptions in homeostasis. CONCLUSIONS: Changing the lighting conditions led to changes in almost all the physiological parameters that we studied. Catecholamines can be regarded as a synchronization super system of split-level circadian oscillators. We established a correlation between hypothalamic levels of Bmal1 and urinary catecholamine concentrations. The magnitude of changes in the GM taxonomic composition was different for LL/LD and DD/LD but the direction of these changes was similar. As for the predicted functional properties of the GM which characterize its metabolic activity, they didn't change as dramatically as the taxonomic composition. All differences may be viewed as a compensatory reaction to new environmental conditions and the organism has adapted to those conditions.


Subject(s)
Catecholamines/urine , Circadian Clocks/physiology , Circadian Rhythm Signaling Peptides and Proteins/metabolism , Circadian Rhythm/physiology , Gastrointestinal Microbiome/physiology , Reactive Oxygen Species/metabolism , Animals , Darkness , Light , Male , Rats
7.
Arch Biochem Biophys ; 671: 111-122, 2019 08 15.
Article in English | MEDLINE | ID: mdl-31251922

ABSTRACT

In this study, we identified a new gene (aph(3″)-Id) coding for a streptomycin phosphotransferase by using phylogenetic comparative analysis of the genome of the oxytetracycline-producing strain Streptomyces rimosus ATCC 10970. Cloning the aph(3″)-Id gene in E.coli and inducing its expression led to an increase in the minimum inhibitory concentration of the recombinant E.coli strain to streptomycin reaching 350 µg/ml. To evaluate the phosphotransferase activity of the recombinant protein APH(3″)-Id we carried out thin-layer chromatography of the putative 32P-labeled streptomycin phosphate. We also performed a spectrophotometric analysis to determine the production of ADP coupled to NADH oxidation. Here are the kinetic parameters of the streptomycin phosphotransferase APH(3″)-Id: Km 80.4 µM, Vmax 6.45 µmol/min/mg and kcat 1.73 s-1. We demonstrated for the first time the ability of the aminoglycoside phototransferase (APH(3″)-Id) to undergo autophosphorylation in vitro. The 3D structures of APH(3″)-Id in its unliganded state and in ternary complex with streptomycin and ADP were obtained. The structure of the ternary complex is the first example of this class of enzymes with bound streptomycin. Comparison of the obtained structures with those of other aminoglycoside phosphotransferases revealed peculiar structure of the substrate-binding pocket reflecting its specificity to a particular antibiotic.


Subject(s)
Bacterial Proteins/chemistry , Phosphotransferases (Alcohol Group Acceptor)/chemistry , Streptomyces rimosus/enzymology , Amino Acid Sequence , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Bacterial Proteins/isolation & purification , Computational Biology , Escherichia coli/drug effects , Escherichia coli/genetics , Genes, Bacterial , Phosphorylation , Phosphotransferases (Alcohol Group Acceptor)/genetics , Phosphotransferases (Alcohol Group Acceptor)/isolation & purification , Phylogeny , Protein Processing, Post-Translational , Protein Structure, Tertiary , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Sequence Alignment , Streptomycin/pharmacology
8.
J Basic Microbiol ; 58(9): 739-746, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29963725

ABSTRACT

We describe Streptomyces fradiae mechanisms of sensitivity to nitrone-oligomycin A, a derivative of oligomycin A. We obtained S. fradiae-nitR+ bld, a nitrone-oligomycin A resistant mutant with a «bald¼ phenotype. Comparative genomic analysis of the wild-type S. fradiae ATCC19609 and S. fradiae-nitR+ bld revealed a mutation in padR - a gene encoding a multifunction transcription regulator, which resulted in the amino acid replacement in a highly conserved DNA-binding domain. Bioinformatics genome analysis of S. fradiae ATCC19609 discovered a PadR binding site 13 bp upstream the start codon of the marR transcription factor gene. Induction of S. fradiaenitR+ bld and w.t. strains with nitrone-oligomycin A lead to a significant increase in expression level of the marR gene in the w.t. strain, but no change observed in mutant strain. We identified differences between DNA-protein interactions of the mutant and native PadR proteins with its putative binding site in S. fradiae ATCC19609. This allowed us to suggest that the padR gene, that harbored a single nucleotide mutation in the S. fradiaenitR+ bld strain, might be involved in the mechanism of resistance to nitrone-oligomycin A. We assume the participation of the transcriptional factorpadR in the formation of the bald phenotype.


Subject(s)
Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Drug Resistance, Bacterial/genetics , Nitrogen Oxides/pharmacology , Oligomycins/pharmacology , Streptomyces/drug effects , Streptomyces/genetics , Anti-Bacterial Agents/pharmacology , Binding Sites/genetics , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Drug Resistance, Bacterial/physiology , Gene Expression Regulation, Bacterial , Genome, Bacterial/genetics , Mutation , Protein Binding , Streptomyces/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism
9.
Biochem Biophys Res Commun ; 477(4): 595-601, 2016 09 02.
Article in English | MEDLINE | ID: mdl-27338640

ABSTRACT

Aminoglycoside phosphotransferases represent a broad class of enzymes that promote bacterial resistance to aminoglycoside antibiotics via the phosphorylation of hydroxyl groups in the latter. Here we report the spatial structure of the 3'-aminoglycoside phosphotransferase of novel VIII class (AphVIII) solved by X-ray diffraction method with a resolution of 2.15 Å. Deep analysis of APHVIII structure and its comparison with known structures of aminoglycoside phosphotransferases of various types reveals that AphVIII has a typical two-domain fold and, however, possesses some unique characteristics that distinguish the enzyme from its known homologues. The most important difference is the presence of the activation loop with unique Ser146 residue. We demonstrate that in the apo-state of the enzyme the activation loop does not interact with other parts of the enzyme and seems to adopt catalytically competent state only after substrate binding.


Subject(s)
Kanamycin Kinase/chemistry , Streptomyces rimosus/enzymology , Binding Sites , Crystallography, X-Ray , Enzyme Activation , Kanamycin Kinase/metabolism , Models, Molecular , Nucleotides/metabolism , Phosphorylation , Protein Conformation , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism
10.
Bioorg Med Chem Lett ; 26(11): 2645-8, 2016 06 01.
Article in English | MEDLINE | ID: mdl-27107949

ABSTRACT

Synthetic routes to novel N-(purin-6-yl)- and N-(2-aminopurin-6-yl) conjugates with amino acids and glycine-containing dipeptides were developed. In vitro testing of 42 new and known compounds made it possible to reveal a series of N-(purin-6-yl)- and N-(2-aminopurin-6-yl) conjugates exhibiting significant antimycobacterial activity against Mycobacterium tuberculosis H37Rv, Mycobacterium avium, Mycobacterium terrae, and multidrug-resistant M. tuberculosis strain isolated from tuberculosis patients in the Ural region (Russia). N-(2-Aminopurin-6-yl)- and N-(purin-6-yl)-glycyl-(S)-glutamic acids were the most active compounds.


Subject(s)
Amino Acids/pharmacology , Anti-Bacterial Agents/pharmacology , Dipeptides/pharmacology , Mycobacterium/drug effects , Amino Acids/chemical synthesis , Amino Acids/chemistry , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Dipeptides/chemical synthesis , Dipeptides/chemistry , Dose-Response Relationship, Drug , Microbial Sensitivity Tests , Molecular Structure , Structure-Activity Relationship
11.
Microb Ecol ; 70(3): 819-34, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25894918

ABSTRACT

In this study, we report the first completely annotated genome sequence of the Russia origin Bifidobacterium longum subsp. longum strain GT15. Comparative genomic analysis of this genome with other available completely annotated genome sequences of B. longum strains isolated from other countries has revealed a high degree of conservation and synteny across the entire genomes. However, it was discovered that the open reading frames to 35 genes were detected only from the B. longum GT15 genome and absent from other genomes B. longum strains (not of Russian origin). These so-called unique genes (UGs) represent a total length of 39,066 bp, with G + C content ranging from 37 to 65 %. Interestingly, certain genes were detected in other B. longum strains of Russian origin. In our analysis, we examined genes for global regulatory systems: proteins of toxin-antitoxin (TA) systems type II, serine/threonine protein kinases (STPKs) of eukaryotic type, and genes of the WhiB-like family proteins. In addition, we have made in silico analysis of all the most significant probiotic genes and considered genes involved in epigenetic regulation and genes responsible for producing various neuromediators. This genome sequence may elucidate the biology of this probiotic strain as a promising candidate for practical (pharmaceutical) applications.


Subject(s)
Bifidobacterium/genetics , Chromosomes, Bacterial/genetics , Genome, Bacterial , Bifidobacterium/metabolism , Chromosome Mapping , Chromosomes, Bacterial/metabolism , Epigenesis, Genetic , Molecular Sequence Data , Phylogeny , Russia , Sequence Analysis, DNA
12.
J Basic Microbiol ; 55(8): 982-91, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25832734

ABSTRACT

Lactobacilli are important microorganisms in various activities, for example, diary products, meat ripening, bread and pickles, but, moreover, are associated directly with human skin and cavities (e.g., mouth, gut, or vagina). Some of them are used as probiotics. Therefore, the molecular biological investigation of these bacteria is important. Earlier we described several toxin antitoxin systems (type II) in lactobacilli. Here, we describe the structure and transcriptional regulation of genes, encoding TA system YefM-YoeB(Lrh) in three strains of Lactobacillus rhamnosus comparing stationary and exponential growth phases, the influence of stress factors and mRNA stability. The same TA system is responding to physiological and stress conditions differently in related strains. Using primer extension and RLM-RACE methods we determined three transcription start sites of RNAs in the operon. The promoter region of the operon is preceded by a conserved BOX element occurring at multiple positions in the genomes of L. rhamnosus strains. Downstream of and partially overlapping with the 3' end of the yoeB(Lrh) toxin gene, a divergently transcribed unexpected RNA was detected.


Subject(s)
Bacterial Proteins/genetics , Bacterial Toxins/genetics , Gene Expression Regulation, Bacterial , Lacticaseibacillus rhamnosus/genetics , Lacticaseibacillus rhamnosus/isolation & purification , Female , Genes, Bacterial , Genome, Bacterial , Humans , Infant , Lacticaseibacillus rhamnosus/growth & development , Operon , Promoter Regions, Genetic , RNA Stability , Saliva/microbiology , Stress, Physiological , Vagina/microbiology
13.
Arch Microbiol ; 196(2): 125-36, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24395073

ABSTRACT

Six genes encoding the bifidobacterial Hanks-type (eukaryote-like) serine/threonine protein kinases (STPK) were identified and classified. The genome of each bifidobacterial strain contains four conserved genes and one species-specific gene. Bifidobacterium longum and Bifidobacterium bifidum possess the unique gene found only in these species. The STPK genes of Russian industrial probiotic strain B. longum B379M were cloned and sequenced. The expression of these genes in Escherichia coli and bifidobacteria was observed. Autophosphorylation of the conserved STPK Pkb5 and species-specific STPK Pkb2 was demonstrated. This is the first report on Hanks-type STPK in bifidobacteria.


Subject(s)
Bifidobacterium/enzymology , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Amino Acid Sequence , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Bifidobacterium/classification , Bifidobacterium/genetics , Catalytic Domain , Escherichia coli/genetics , Escherichia coli/metabolism , Genes, Bacterial , Molecular Sequence Data , Phosphorylation , Phylogeny , Probiotics , Protein Serine-Threonine Kinases/chemistry , Sequence Analysis, DNA , Species Specificity
14.
Front Microbiol ; 15: 1416688, 2024.
Article in English | MEDLINE | ID: mdl-38919499

ABSTRACT

In recent years, there has been an increasing tendency to create drugs based on certain commensal bacteria of the human microbiota and their ingredients, primarily focusing on live biotherapeutics (LBPs) and postbiotics. The creation of such drugs, termed pharmacobiotics, necessitates an understanding of their mechanisms of action and the identification of pharmacologically active ingredients that determine their target properties. Typically, these are complexes of biologically active substances synthesized by specific strains, promoted as LBPs or postbiotics (including vesicles): proteins, enzymes, low molecular weight metabolites, small RNAs, etc. This study employs omics technologies, including genomics, proteomics, and metabolomics, to explore the potential of Limosilactobacillus fermentum U-21 for innovative LBP and postbiotic formulations targeting neuroinflammatory processes. Proteomic techniques identified and quantified proteins expressed by L. fermentum U-21, highlighting their functional attributes and potential applications. Key identified proteins include ATP-dependent Clp protease (ClpL), chaperone protein DnaK, protein GrpE, thioredoxin reductase, LysM peptidoglycan-binding domain-containing protein, and NlpC/P60 domain-containing protein, which have roles in disaggregase, antioxidant, and immunomodulatory activities. Metabolomic analysis provided insights into small-molecule metabolites produced during fermentation, revealing compounds with anti-neuroinflammatory activity. Significant metabolites produced by L. fermentum U-21 include GABA (γ-aminobutyric acid), niacin, aucubin, and scyllo-inositol. GABA was found to stabilize neuronal activity, potentially counteracting neurodegenerative processes. Niacin, essential for optimal nervous system function, was detected in vesicles and culture fluid, and it modulates cytokine production, maintaining immune homeostasis. Aucubin, an iridoid glycoside usually secreted by plants, was identified as having antioxidant properties, addressing issues of bioavailability for therapeutic use. Scyllo-inositol, identified in vesicles, acts as a chemical chaperone, reducing abnormal protein clumps linked to neurodegenerative diseases. These findings demonstrate the capability of L. fermentum U-21 to produce bioactive substances that could be harnessed in the development of pharmacobiotics for neurodegenerative diseases, contributing to their immunomodulatory, anti-neuroinflammatory, and neuromodulatory activities. Data of the HPLC-MS/MS analysis are available via ProteomeXchange with identifier PXD050857.

15.
Bioorg Med Chem ; 21(11): 2918-24, 2013 Jun 01.
Article in English | MEDLINE | ID: mdl-23623676

ABSTRACT

A novel way of chemical modification of the macrolide antibiotic oligomycin A (1) at the side chain was developed. Mesylation of 1 with methane sulfonyl chloride in the presence of 4-dimethylaminopyridine produced 33-O-mesyl oligomycin in 56% yield. Reactions of this intermediate with sodium azide produced the key derivative 33-azido-33-deoxy-oligomycin A in 60% yield. 1,3-Dipolar cycloaddition reaction with propiolic acid, methyl ester of propiolic acid, and phenyl acetylene resulted in 33-deoxy-33-(1,2,3-triazol-1-yl)oligomycin A derivatives substituted at N4 of the triazole cycle. The mesylated oligomycin A and 33-deoxy-33-azidooligomycin A did not inhibit F0F1 ATFase ATPase; however, 33-azido-33-deoxy-oligomycin A and the derivatives containing 4-phenyltriazole, 4-methoxycarbonyl-triazole and 3-dimethylaminoethyl amide of carboxyltriazole substituents demonstrated a high cytotoxicity against K562 leukemia and HCT116 human colon carcinoma cell lines whereas non-malignant skin fibroblasts were less sensitive to these compounds. Novel series of oligomycin A derivatives allow for the search of intracellular molecules beyond F0F1 ATP synthase relevant to the cytotoxic properties of this perspective chemical class.


Subject(s)
Anti-Bacterial Agents/chemical synthesis , Cytotoxins/chemical synthesis , Oligomycins/chemistry , Triazoles/chemical synthesis , 4-Aminopyridine/analogs & derivatives , 4-Aminopyridine/chemistry , Amino Acid Sequence , Anti-Bacterial Agents/pharmacology , Binding Sites , Cell Line, Tumor , Cycloaddition Reaction , Cytotoxins/pharmacology , Fibroblasts/cytology , Fibroblasts/drug effects , Fibroblasts/enzymology , Humans , Mesylates/chemistry , Molecular Sequence Data , Oligomycins/pharmacology , Proton-Translocating ATPases/chemistry , Proton-Translocating ATPases/metabolism , Skin/cytology , Skin/drug effects , Skin/enzymology , Sodium Azide/chemistry , Streptomyces/drug effects , Streptomyces/growth & development , Triazoles/pharmacology
16.
Biology (Basel) ; 12(4)2023 Mar 27.
Article in English | MEDLINE | ID: mdl-37106707

ABSTRACT

Drug resistance (DR) in Mycobacterium tuberculosis is the main problem in fighting tuberculosis (TB). This pathogenic bacterium has several types of DR implementation: acquired and intrinsic DR. Recent studies have shown that exposure to various antibiotics activates multiple genes, including genes responsible for intrinsic DR. To date, there is evidence of the acquisition of resistance at concentrations well below the standard MICs. In this study, we aimed to investigate the mechanism of intrinsic drug cross-resistance induction by subinhibitory concentrations of antibiotics. We showed that pretreatment of M. smegmatis with low doses of antibiotics (kanamycin and ofloxacin) induced drug resistance. This effect may be caused by a change in the expression of transcriptional regulators of the mycobacterial resistome, in particular the main transcriptional regulator whiB7.

17.
Microbiome Res Rep ; 2(2): 10, 2023.
Article in English | MEDLINE | ID: mdl-38047275

ABSTRACT

Aim: This study is mainly devoted to determining the ability of ∆FN3.1 protein fragments of Bifidobacterium (B.) longum subsp. longum GT15, namely two FN3 domains (2D FN3) and a C-terminal domain (CD FN3), to bind to tumor necrosis factor-alpha (TNF-α). Methods: Fragments of the fn3 gene encoding the 2D FN3 and CD FN3 were cloned in Escherichia (E.) coli. In order to assess the binding specificity between 2D FN3 and CD FN3 to TNFα, we employed the previously developed sandwich ELISA system to detect any specific interactions between the purified protein and any of the studied cytokines. The trRosetta software was used to build 3D models of the ∆FN3.1, 2D FN3, and CD FN3 proteins. The detection of polymorphism in the amino acid sequences of the studied proteins and the analysis of human gut-derived bacterial proteins carrying FN3 domains were performed in silico. Results: We experimentally showed that neither 2D FN3 nor CD FN3 alone can bind to TNFα. Prediction of the 3D structures of ΔFN3.1, 2D FN3, and CD FN3 suggested that only ΔFN3.1 can form a pocket allowing binding with TNFα to occur. Polymorphism analysis of amino acid sequences of ΔFN3.1 proteins in B. longum strains uncovered substitutions that can alter the conformation of the spatial structure of the ΔFN3.1 protein. We also analyzed human gut-derived bacterial proteins harboring FN3 domains which allowed us to differentiate between those containing motifs of cytokine receptors (MCRs) in their FN3 domains and those lacking them. Conclusion: Only the complete ∆FN3.1 protein can selectively bind to TNFα. Analysis of 3D models of the 2D FN3, CD FN3, and ΔFN3.1 proteins showed that only the ΔFN3.1 protein is potentially capable of forming a pocket allowing TNFα binding to occur. Only FN3 domains containing MCRs exhibited sequence homology with FN3 domains of human proteins.

18.
Foods ; 12(18)2023 Sep 07.
Article in English | MEDLINE | ID: mdl-37761064

ABSTRACT

Bifidobacterium is a predominant and important genus in the bacterial population of the human gut microbiota. Despite the increasing number of studies on the beneficial functionality of bifidobacteria for human health, knowledge about their antioxidant potential is still insufficient. Several in vivo and in vitro studies of Bifidobacterium strains and their cellular components have shown good antioxidant capacity that provided a certain protection of their own and the host's cells. Our work presents the data of transcriptomic, proteomic, and metabolomic analyses of the growing and stationary culture of the probiotic strain B. longum subsp. longum GT15 after exposure to hydrogen peroxide for 2 h and oxygen for 2 and 4 h. The results of the analysis of the sequenced genome of B. longum GT15 showed the presence of 16 gene-encoding proteins with known antioxidant functions. The results of the full transcriptomic analysis demonstrated a more than two-fold increase of levels of transcripts for eleven genes, encoding proteins with antioxidant functions. Proteomic data analysis showed an increased level of more than two times for glutaredoxin and thioredoxin after the exposure to oxygen, which indicates that the thioredoxin-dependent antioxidant system may be the major redox homeostasis system in B. longum bacteria. We also found that the levels of proteins presumably involved in global stress, amino acid metabolism, nucleotide and carbohydrate metabolism, and transport had significantly increased in response to oxidative stress. The metabolic fingerprint analysis also showed good discrimination between cells responding to oxidative stress and the untreated controls. Our results provide a greater understanding of the mechanism of oxidative stress response in B. longum and the factors that contribute to its survival in functional food products.

19.
Pharmaceuticals (Basel) ; 16(11)2023 Nov 06.
Article in English | MEDLINE | ID: mdl-38004430

ABSTRACT

The World Health Organization (WHO) reports that tuberculosis (TB) is one of the top 10 leading causes of global mortality. The increasing incidence of multidrug-resistant TB highlights the urgent need for an intensified quest to discover innovative anti-TB medications In this study, we investigated four new derivatives from the quinoxaline-2-carboxylic acid 1,4-dioxide class. New 3-methylquinoxaline 1,4-dioxides with a variation in substituents at positions 2 and 6(7) were synthesized via nucleophilic aromatic substitution with amines and assessed against a Mycobacteria spp. Compound 4 showed high antimycobacterial activity (1.25 µg/mL against M. tuberculosis) and low toxicity in vivo in mice. Selection and whole-genomic sequencing of spontaneous drug-resistant M. smegmatis mutants revealed a high number of single-nucleotide polymorphisms, confirming the predicted mode of action of the quinoxaline-2-carboxylic acid 1,4-dioxide 4 as a DNA-damaging agent. Subsequent reverse genetics methods confirmed that mutations in the genes MSMEG_4646, MSMEG_5122, and MSMEG_1380 mediate resistance to these compounds. Overall, the derivatives of quinoxaline-2-carboxylic acid 1,4-dioxide present a promising scaffold for the development of innovative antimycobacterial drugs.

20.
Nat Neurosci ; 26(7): 1208-1217, 2023 07.
Article in English | MEDLINE | ID: mdl-37365313

ABSTRACT

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by heterogeneous cognitive, behavioral and communication impairments. Disruption of the gut-brain axis (GBA) has been implicated in ASD although with limited reproducibility across studies. In this study, we developed a Bayesian differential ranking algorithm to identify ASD-associated molecular and taxa profiles across 10 cross-sectional microbiome datasets and 15 other datasets, including dietary patterns, metabolomics, cytokine profiles and human brain gene expression profiles. We found a functional architecture along the GBA that correlates with heterogeneity of ASD phenotypes, and it is characterized by ASD-associated amino acid, carbohydrate and lipid profiles predominantly encoded by microbial species in the genera Prevotella, Bifidobacterium, Desulfovibrio and Bacteroides and correlates with brain gene expression changes, restrictive dietary patterns and pro-inflammatory cytokine profiles. The functional architecture revealed in age-matched and sex-matched cohorts is not present in sibling-matched cohorts. We also show a strong association between temporal changes in microbiome composition and ASD phenotypes. In summary, we propose a framework to leverage multi-omic datasets from well-defined cohorts and investigate how the GBA influences ASD.


Subject(s)
Autism Spectrum Disorder , Gastrointestinal Microbiome , Humans , Gastrointestinal Microbiome/genetics , Brain-Gut Axis , Autism Spectrum Disorder/genetics , Autism Spectrum Disorder/metabolism , Cross-Sectional Studies , Bayes Theorem , Reproducibility of Results , Cytokines
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