A5075744550- Gut microbiota and health
- Probiotics and Fermented Foods
- Bacteriophages and microbial interactions
- Clostridium difficile and Clostridium perfringens research
- Escherichia coli research studies
- Bacterial Genetics and Biotechnology
- Genomics and Phylogenetic Studies
- Salmonella and Campylobacter epidemiology
- Listeria monocytogenes in Food Safety
- Bacillus and Francisella bacterial research
- Viral gastroenteritis research and epidemiology
- Microbial Inactivation Methods
- Gastrointestinal motility and disorders
- Inflammatory Bowel Disease
- Bacterial biofilms and quorum sensing
- Microbial Community Ecology and Physiology
- Microbial infections and disease research
- Food composition and properties
- Essential Oils and Antimicrobial Activity
- Diet and metabolism studies
- Enzyme Production and Characterization
- Microbial Metabolites in Food Biotechnology
- Yersinia bacterium, plague, ectoparasites research
- Fermentation and Sensory Analysis
- Mycobacterium research and diagnosis
National Renewable Energy Laboratory
2025
Texas Tech University
2025
University of Nebraska–Lincoln
2015-2024
Princeton University
1994-2014
Midwestern University
2014
University of British Columbia
1996
The University of Texas Health Science Center at San Antonio
1989-1993
Iowa State University
1987-1989
Lactic acid-producing bacteria are associated with various plant and animal niches play a key role in the production of fermented foods beverages. We report nine genome sequences representing phylogenetic functional diversity these bacteria. The small genomes lactic acid encode broad repertoire transporters for efficient carbon nitrogen acquisition from nutritionally rich environments they inhabit reflect limited range biosynthetic capabilities that indicate both prototrophic auxotrophic...
In vertebrates, including humans, individuals harbor gut microbial communities whose species composition and relative proportions of dominant groups are tremendously varied. Although external stochastic factors clearly contribute to the individuality microbiota, fundamental principles dictating how environmental host genetic combine shape this complex ecosystem largely unknown require systematic study. Here we examined that affect microbiota in a large ( n = 645) mouse advanced intercross...
ABSTRACT The mammalian gastrointestinal microbiota exerts a strong influence on host lipid and cholesterol metabolism. In this study, we have characterized the interplay among diet, gut microbial ecology, metabolism in hamster model of hypercholesterolemia. Previous work had shown that grain sorghum extract (GSL) included diet significantly improved high-density lipoprotein (HDL)/non-HDL equilibrium (T. P. Carr, C. L. Weller, V. Schlegel, S. Cuppett, D. M. Guderian, Jr., K. R. Johnson, J....
Recent research has provided mechanistic insight into the important contributions of gut microbiota to vertebrate biology, but questions remain about evolutionary processes that have shaped this symbiosis. In present study, we showed in experiments with gnotobiotic mice evolution Lactobacillus reuteri rodents resulted emergence host specialization. To identify genomic events marking adaptations murine host, compared genome rodent isolate L. 100-23 human F275, and identified hundreds genes...
The gastrointestinal tract harbors a complex and diverse microbiota that has an important role in host metabolism. Microbial diversity is influenced by combination of environmental genetic factors associated with several polygenic diseases. In this study we combined next-generation sequencing, mapping, set physiological traits the BXD mouse population to explore explain differences gut its impact on metabolic traits. Molecular profiling revealed quantitative microbial composition among...
While wine fermentation has long been known to involve complex microbial communities, the composition and role of bacteria other than a select set lactic acid (LAB) often assumed either negligible or detrimental. This study served as pilot for using barcoded amplicon next-generation sequencing profile bacterial community structure in wines grape musts, comparing taxonomic depth achieved by two different domains prokaryotic 16S rDNA (V4 V5). was designed serve goals: 1) empirically determine...
The factors that govern assembly of the gut microbiota are insufficiently understood. Here, we test hypothesis inter-individual variation can arise solely from differences in order and timing by which is colonized early life. Experiments mice were inoculated sequence either with two complex seed communities or a cocktail four bacterial strains community revealed colonization influenced both outcome ecological success individual colonizers. Historical contingency priority effects also...
ABSTRACT Listeria monocytogenes is well known for its robust physiology, which permits growth at low temperatures under conditions of high osmolarity and pH. Although studies have provided insight into the mechanisms used by L. to allay physiological consequences these adverse environments, little about how responses are coordinated. In presented here, we cloned sigB gene several rsb genes from , encoding homologs alternative sigma factor ς B RsbUVWX proteins, govern transcription a general...
Colonization of the gastrointestinal tract and composition microbiota may be influenced by components diet, including trace elements. To understand how selenium regulates intestinal microflora, we used high-throughput sequencing to examine gut mice maintained on selenium-deficient, selenium-sufficient, selenium-enriched diets. The diversity increased as a result in diet. Specific phylotypes showed differential effects selenium, even within genus, implying that had unique across microbial...
sigma B is a secondary factor of Bacillus subtilis. RNA polymerase containing transcribes subset genes that are expressed after heat shock or the onset stationary phase growth. Three (rsbV, rsbW, and rsbX), cotranscribed with structural gene (sigB), regulate B-dependent expression. RsbW primary inhibitor this system other products acting upstream in regulatory pathway. Evidence now presented inhibits transcription by binding to blocking formation B-containing holoenzyme. Antibodies specific...
Multilocus-genotyping methods have shown that Escherichia coli O157:H7 is a geographically disseminated clone. However, high-resolution such as pulse-field gel electrophoresis demonstrate significant genomic diversity among different isolates. To assess the genetic relationship of human and bovine isolates E. in detail, we developed an octamer-based genome-scanning methodology, which compares distance between over-represented, strand-biased octamers occur genome. Comparison products derived...
Abstract Background Genetic analysis of Escherichia coli O157:H7 strains has shown divergence into two distinct lineages, lineages I and II, that appear to have ecological characteristics, with lineage more commonly associated human disease. In this study, microarray-based comparative genomic hybridization (CGH) was used identify differences among 31 E. belong various phage types (PTs) different lineage-specific polymorphism assay (LSPA) types. Results A total 4,084 out 6,057 ORFs were...
The objective of this study is to investigate individual animal variation bovine fecal microbiota including as affected by diets. Fecal samples were collected from 426 cattle fed 1 3 diets typically feedlot cattle: 1) 143 steers finishing diet (83% dry-rolled corn, 13% corn silage, and 4% supplement), 2) 147 late growing (66% 26% 8% 3) 136 heifers early (70% silage 30% alfalfa haylage). Bacterial 16S rRNA gene amplicons determined using next-generation pyrosequencing technology. A total...
Although vertebrates harbor bacterial communities in their gastrointestinal tract whose composition is host-specific, little known about the mechanisms by which lineages become selected. The goal of this study was to characterize ecological processes that mediate host-specificity vertebrate gut symbiont Lactobacillus reuteri, and systematically identify factors are involved. Experiments with monoassociated mice revealed ability L. reuteri form epithelial biofilms mouse forestomach strictly...
Abstract Background Individuality in the species composition of vertebrate gut microbiota is driven by a combination host and environmental factors that have largely been studied independently. We convergence these G 10 mouse population generated from cross between two strains to search for quantitative trait loci (QTLs) affect or ileal Immunoglobulin A (IgA) expression mice fed normal high-fat diets. Results found 42 microbiota-specific QTLs 27 different genomic regions relative abundances...
Recent advances in next-generation sequencing (NGS) technology enable researchers to collect a large volume of metagenomic data. These data provide valuable resources for investigating interactions between the microbiome and host environmental/clinical factors. In addition well-known properties count measurements, example, varied total sequence reads across samples, over-dispersion zero-inflation, studies usually samples with hierarchical structures, which introduce correlation among thus...
Emerging evidence indicates that antibiotic-induced dysbiosis can play an etiological role in the pathogenesis of neuropsychiatric disorders. However, most this comes from rodent models. The objective study was to evaluate if gut elicit changes metabolites and behavior indicative gut-brain axis disruption common marmosets (Callithrix jacchus) – a nonhuman primate model often used sociability stress. We were able successfully induce using custom antibiotic cocktail (vancomycin, enrofloxacin...
ABSTRACT The activity of ς B in Listeria monocytogenes is stimulated by high osmolarity and necessary for efficient uptake osmoprotectants. Here we demonstrate that, during cold shock, contributes to adaptation a growth phase-dependent manner accumulation betaine carnitine as cryoprotectants.
The sigB operon of Bacillus subtilis encodes sigma B plus three additional proteins (RsbV, RsbW, and RsbX) that regulate activity. Using an anti-sigma monoclonal antibody to monitor the levels protein, PSPAC control expression operon, a ctc-lacZ reporter system activity, we observed rsbV rsbW products activity at ctc promoter independently their effects on levels. In contrast, RsbX was found have no effect when controlled by PSPAC. data are consistent with RsbV RsbW being regulators acting...
ABSTRACT Non-sorbitol-fermenting, β-glucuronidase-negative Escherichia coli O157:H7 strains are regarded as a clone complex, and populations from different geographical locations believed to share recent common ancestor. Despite their relatedness, high-resolution genotyping methods can detect significant genome variation among populations. Phylogenetic analysis of data these has shown that subpopulations geographically unlinked continents be divided into two primary phylogenetic lineages,...
The sigB operon of Bacillus subtilis encodes sigma B and three additional open reading frames (orfV, orfW, orfX). Having previously mapped several mutations that alter the induction pattern a B-dependent promoter (ctc) to regions cloned B. DNA which contain these frames, we directly tested regulatory potential orfV, orfX by creating null alleles each genes examining effects mutations, either singly or in pairs, on transcription ctc operon. Using lacZ reporter gene fusions Northern (RNA) blot...