Colonization of the live biotherapeutic product VE303 and modulation of the microbiota and metabolites in healthy volunteers.

Manipulation of the gut microbiota via fecal microbiota transplantation (FMT) has shown clinical promise in diseases such as recurrent Clostridioides difficile infection (rCDI). However, the variable nature of this approach makes it challenging to describe the relationship between fecal strain colonization, corresponding microbiota changes, and clinical efficacy. Live biotherapeutic products (LBPs) consisting of defined consortia of clonal bacterial isolates have been proposed as an alternative therapeutic class because of their promising preclinical results and safety profile.

Hydrogen peroxide-producing pyruvate oxidase from Lactobacillus delbrueckii is catalytically activated by phosphotidylethanolamine.

Background: Pyruvate oxidase (Pox) is an important enzyme in bacterial metabolism for increasing ATP production and providing a fitness advantage via hydrogen peroxide production. However, few Pox enzymes have been characterized from bacterial species. The tetrameric non-hydrogen-peroxide producing Pox from E.

Interspecies Inhibition of by Yogurt-Derived Requires Active Pyruvate Oxidase.

Despite a growing interest in using probiotic microorganisms to prevent disease, the mechanisms by which probiotics exert their action require further investigation. is an important pathogen implicated in the development of periodontitis. We isolated several strains of from dairy products and examined their ability to inhibit growth We observed strain-specific inhibition of growth Whole-genome sequencing of inhibitory and noninhibitory strains of revealed significant genetic differences supporting the strain specificity of the interaction.

Using Tn-seq To Identify Pigmentation-Related Genes of Porphyromonas gingivalis: Characterization of the Role of a Putative Glycosyltransferase.

Cellular pigmentation is an important virulence factor of the oral pathogen Pigmentation has been associated with many bacterial functions, including but not limited to colonization, maintaining a local anaerobic environment by binding oxygen molecules, and defense against reactive oxygen species (ROS) produced by immune cells. Pigmentation-associated loci identified to date have involved lipopolysaccharide, fimbriae, and heme acquisition and processing. We utilized a transposon mutant library of strain ATCC 33277 and screened for pigmentation-defective colonies using massively parallel sequencing of the transposon junctions (Tn-seq) to identify genes involved in pigmentation.

Interactions of the Metalloregulatory Protein SloR from Streptococcus mutans with Its Metal Ion Effectors and DNA Binding Site.

Unlabelled: Streptococcus mutans is the causative agent of dental caries, a significant concern for human health, and therefore an attractive target for therapeutics development. Previous work in our laboratory has identified a homodimeric, manganese-dependent repressor protein, SloR, as an important regulator of cariogenesis and has used site-directed mutagenesis to map functions to specific regions of the protein. Here we extend those studies to better understand the structural interaction between SloR and its operator and its effector metal ions.

Characterization of the functional domains of the SloR metalloregulatory protein in Streptococcus mutans.

Streptococcus mutans is a commensal member of the healthy plaque biofilm and the primary causative agent of dental caries. The present study is an investigation of SloR, a 25-kDa metalloregulatory protein that modulates genes responsible for S. mutans-induced cariogenesis.