Project description:We used a whole genome array containing 97.4 % of the annotated genes of Lactobacillus acidophilus NCFM, a probiotic culture that belongs to the lactic acid bacteria group, to identify genes that are differentially expressed under several stress conditions. Keywords: Stress response
Project description:The human microbiota is believed to influence health. Microbiome dysbiosis may be linked to neurological conditions like Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS) and Huntington’s disease (HD). We report the ability of a probiotic bacterial strain in halting neurodegeneration phenotypes. We show that Lacticaseibacillus rhamnosus HA-114 is neuroprotective in C. elegans models of ALS and HD. Our results show that neuroprotection from L. rhamnosus HA-114 is unique from other L. rhamnosus strains, and resides in its fatty acid content. Neuroprotection by L. rhamnosus HA-114 requires acdh-1/ACADSB, kat-1/ACAT1 and elo-6/ELOVL3/6, which are key fatty acid metabolism and mitochondrial b-oxidation genes. Our data suggest that disrupted lipid metabolism contributes to neurodegeneration and that dietary intervention with L. rhamnosus HA-114 restores lipid homeostasis and energy balance through mitochondrial b-oxidation. L. rhamnosus HA-114 is suitable for human consumption opening the possibility of modifying disease progression by dietary intervention.
2021-12-05 | GSE189988 | GEO
Project description:Lactic acid bacteria used for fermentation
Project description:Lacticaseibacillus rhamnosus Lcr35 is a well-known bacterial strain whose efficiency in preventing recurrent vulvovaginal candidiasis has been largely demonstrated in clinical trials. The presence of sodium thiosulfate (STS) has been shown to enhance its ability to inhibit the growth of C. albicans strains. In this study, we confirmed that Lcr35 has a fungicidal effect not only on the planktonic form of C. albicans but also on other life forms such as hypha and biofilm. Transcriptomic analysis showed that the presence of C. albicans induced a metabolic adaptation of Lcr35 potentially associated with a competitive advantage over yeast cells. However, STS alone had no impact on the global gene expression of Lcr35, which is not in favor of the involvement of an enzymatic transformation of STS. Comparative gas chromatography- mass spectrometry analysis of the organic phase from cell-free supernatant (CFS) fractions obtained from Lcr35 cultures performed in the presence and absence of STS identified elemental sulfur (S0) in the samples initially containing STS. In addition, the anti-candida activity of CFS from STS-containing cultures was shown to be pH-dependent and occurred at acidic pH lower than 5. We next investigated the antifungal activity of lactic acid and acetic acid, the two main organic acids produced by Lactobacillus spp. The two molecules affected the viability of C. albicans but only at pH 3.5 and in a dose-dependent manner, an antifungal effect that was enhanced in samples containing STS in which the thiosulfate was decomposed into S0. In conclusion, the use of STS as an excipient in the manufacturing process of Lcr35 exerted a dual action since the production of organic acids by Lcr35 facilitates the decomposition of thiosulfate into S0, thereby enhancing the bacteria’s own anti-fungal effect.
Project description:Lacticaseibacillus rhamnosus CM MSU 529 is the O2-tolerant facultative homofermentative lactic acid bacteria realizing respiratory metabolism when grown in a supplemented with hemin and vitamin K2 nutrient medium. This study describes the effect of aerobic and respiratory conditions on biomass and proteome of strain CM MSU 529 grown in a batch culture. Aeration caused the induction of the biosynthesis of 43 proteins, while 14 proteins were down-regulated as detected by label-free LC-MS/MS. Up-regulated proteins are involved in oxygen consumption (Pox, LctO, pyridoxine 5'-phosphate oxidase), xylulose-5-phosphate conversion (Xfp), pyruvate metabolism (PdhD, AlsS, AlsD), reactive oxygen species (ROS) elimination (Tpx, TrxA, Npx), general stress response (GroES, PfpI, universal stress protein, YqiG), antioxidant production (CysK, DkgA), pyrimidine metabolism (CarA, CarB, PyrE, PyrC, PyrB, PyrR), oligopeptide transport and metabolism (OppA, PepO), maturation and stability of ribosomal subunits (RbfA, VicX). Down-regulated proteins participate in ROS defense (AhpC), citrate and pyruvate consumption (CitE, PflB), oxaloacetate production (AvtA), arginine synthesis (ArgG), amino acid transport (GlnQ), and deoxy-nucleoside biosynthesis (RtpR). Overproduction of purine biosynthesis enzyme (PurE) distinguished cells grown under respiratory conditions from cells grown under aerobiosis. The data obtained shed light on mechanisms providing O2-tolerance and adaptation to aerobic/respiratory conditions in strain CM MSU 529.
Project description:Carbapenem-resistant Acinetobacter baumannii (CRAB) is a recognized nosocomial pathogen with limited therapeutics options. Lactic acid bacteria (LAB) constitute a promising therapeutic alternative. Here we aimed to study the antibacterial properties of a collection of LAB strains using phenotypic and transcriptomic analysis against A. baumannii clinical strains. One strain, Lacticaseibacillus rhamnosus CRL 2244, exerts a strong inhibitory capacity on A. baumannii with a strong killing activity. Scanning electron microscopy images showed changes in the morphology of A. baumannii with an increase formation of outer membrane vesicles. Significant changes in the expression levels a wide variety of genes were observed. Interestingly, most of the modified genes were involved in metabolic pathway known to be associated with bacterial survival. The paa operon, Hut system, and fatty acid degradation were some of the pathways that have been induced. The data reveals the impact of Lcb. rhamnosus CRL 2244 on A. baumannii response, resulting in bacterial stress and subsequent cell death. These findings highlight the antibacterial properties of Lcb. rhamnosus CRL 2244 and its potential as an alternative or complementary strategy for treating infections. Further exploration and development of this LAB as a treatment option could provide valuable alternatives for combating CRAB infections.