GABA production and structure of gadB/gadC genes in Lactobacillus and Bifidobacterium strains from human microbiota.

Gamma-amino butyric acid (GABA) is an active biogenic substance synthesized in plants, fungi, vertebrate animals and bacteria. Lactic acid bacteria are considered the main producers of GABA among bacteria. GABA-producing lactobacilli are isolated from food products such as cheese, yogurt, sourdough, etc. and are the source of bioactive properties assigned to those foods. The ability of human-derived lactobacilli and bifidobacteria to synthesize GABA remains poorly characterized. In this paper, we screened our collection of 135 human-derived Lactobacillus and Bifidobacterium strains for their ability to produce GABA from its precursor monosodium glutamate. Fifty eight strains were able to produce GABA. The most efficient GABA-producers were Bifidobacterium strains (up to 6 g/L). Time profiles of cell growth and GABA production as well as the influence of pyridoxal phosphate on GABA production were studied for L. plantarum 90sk, L. brevis 15f, B. adolescentis 150 and B. angulatum GT102. DNA of these strains was sequenced; the gadB and gadC genes were identified. The presence of these genes was analyzed in 14 metagenomes of healthy individuals. The genes were found in the following genera of bacteria: Bacteroidetes (Bacteroides, Parabacteroides, Alistipes, Odoribacter, Prevotella), Proteobacterium (Esherichia), Firmicutes (Enterococcus), Actinobacteria (Bifidobacterium). These data indicate that gad genes as well as the ability to produce GABA are widely distributed among lactobacilli and bifidobacteria (mainly in L. plantarum, L. brevis, B. adolescentis, B. angulatum, B. dentium) and other gut-derived bacterial species. Perhaps, GABA is involved in the interaction of gut microbiota with the macroorganism and the ability to synthesize GABA may be an important feature in the selection of bacterial strains - psychobiotics.

[Effects of diet on the gut microbiome in patients with depression]. / Vliyanie diety na mikrobiom kishechnika u patsientov s depressiei.

OBJECTIVE: To investigate the effects of diet on the gut microbiota and to assess the relationship of these factors with depression. MATERIAL AND METHODS: Microorganisms that predominate in depressed patients were identified and associations of the identified organisms with the patients' diet were performed. Fourteen depressed patients and 14 healthy volunteers with the same socio-demographic parameters were included in the study. The Hamilton Depression Scale, Generalized Anxiety Disorder Questionnaire, and the Center for Epidemiologic Studies Questionnaire were used. RESULTS: Erysipelatoclostridium and Clostridium innocuum species were 11.3 and 14.4 times higher in depressed patients compared with healthy controls. Fusicatenibacter saccharivorans, Faecalibacterium prausnitzii and Roseburia faecis species, as well as members of the genus Roseburia were statistically significantly more abundant in the healthy volunteers group (6.5, 2.14, 8.75 and 5.2 times more frequently compared to patients). The presence of these microorganisms was correlated with dietary components. CONCLUSION: Our study revealed groups of microorganisms that differ in healthy volunteers and depressed patients. The association of these microorganisms with the diet was shown, which partially confirmed the influence of a «healthy diet¼ on the development of depressive disorders.

[Cholecystostomy in emergent surgery of hepatopancreatobiliary zone organs].

Results of cholecystostomy formation in 26 elderly or senile patients for urgent diseases of hepatopancreatobiliary zone organs and severe coexistent pathology of respiratory organs, cardiovascular system and intoxication, were analyzed. The tactics was proposed and indications for cholecystectomy formation were substantiated.