A5008408591- Bacterial biofilms and quorum sensing
- Bacterial Genetics and Biotechnology
- Genomics and Phylogenetic Studies
- Oral microbiology and periodontitis research
- Legume Nitrogen Fixing Symbiosis
- Protist diversity and phylogeny
- Photoreceptor and optogenetics research
- Plant-Microbe Interactions and Immunity
- Nematode management and characterization studies
- Gut microbiota and health
- Probiotics and Fermented Foods
- Microbial Community Ecology and Physiology
- Amino Acid Enzymes and Metabolism
- Bacterial Identification and Susceptibility Testing
- Diverse Educational Innovations Studies
- Entomopathogenic Microorganisms in Pest Control
- Indigenous and Place-Based Education
- Slime Mold and Myxomycetes Research
- Plant Pathogenic Bacteria Studies
- Molecular Sensors and Ion Detection
- Neuroscience and Neuropharmacology Research
- Vibrio bacteria research studies
- Plant tissue culture and regeneration
- Biocrusts and Microbial Ecology
- bioluminescence and chemiluminescence research
University of Washington
2021-2024
University of Tennessee at Knoxville
2017-2020
University of Oklahoma
2011-2017
Plant (United States)
2014
Cardiff University
2002
Significance Bacteria must respond quickly to environmental changes survive. One way bacteria can stress is by undergoing a lifestyle transition from individual, free-swimming cells surface-associated community called biofilm characterized aggregative growth. The opportunistic pathogen Pseudomonas aeruginosa uses the Wsp chemosensory system sense an unknown cue. Here we show that senses cell envelope stress, specifically conditions promote unfolded or misregulated periplasmic and inner...
Although the influence of microbiomes on health plant hosts is evident, specific mechanisms shaping structure and dynamics microbial communities in phyllosphere rhizosphere are only beginning to become clear. Traditionally, plant–microbe interactions have been studied using cultured isolates but rising use ‘omics tools provides novel snapshots total complex community situ. Here, we discuss recent advances techniques used monitor chemical signals that these relationships above- belowground...
Biofilms are aggregates of microorganisms embedded in an extracellular matrix comprised largely exopolysaccharides (EPSs), nucleic acids, and proteins. Pseudomonas aeruginosa is opportunistic human pathogen that also a model organism for studying biofilms the laboratory. Here, we define novel program biofilm development used by mucoid (alginate-overproducing) P. presence elevated calcium. Calcium cations cross-link negatively charged alginate polymers, resulting individual cells being...
Plant root exudates play critical roles in shaping rhizosphere microbial communities, and the ability of motile bacteria to respond these gradients mediates competitive colonization surfaces. Root are complex chemical mixtures that spatially temporally dynamic. Identifying exact chemical(s) recruitment soil specific regions roots is thus challenging. Here, we connect patterns bacterial chemotaxis responses sensing by chemoreceptors chemicals found exudate identify key signals shape surface...
Two previously uncharacterized strains of Gram-reaction-positive, anaerobic, coccus-shaped bacteria, designated WAL 18896 T and 18898 , were recovered from human wound specimens characterized using phenotypic, chemotaxonomic molecular taxonomic methods. Comparative 16S rRNA gene sequence analysis biochemical characteristics demonstrated that these organisms are genotypically phenotypically distinct represent unidentified sublines within the order Clostridiales in phylum Firmicutes . Pairwise...
ABSTRACT Bacterial chemotaxis receptors provide the sensory inputs that inform direction of navigation in changing environments. Recently, we described bacterial second messenger cyclic di-GMP (c-di-GMP) as a novel regulator subclass receptors. In Azospirillum brasilense , c-di-GMP binds to receptor, Tlp1, and modulates its signaling function during aerotaxis. Here, further characterize role aerotaxis using dichromatic optogenetic system engineered for manipulating intracellular levels real...
The assembly of chemotaxis receptors and signaling proteins into polar arrays is universal in motile chemotactic bacteria. Comparative genome analyses indicate that most bacteria possess multiple systems, experimental evidence suggests from distinct systems integrated. Here, we identify one such mechanism. We show paralogs two assemble together chemoreceptor arrays, forming baseplates comprised both systems. These mixed provide a straightforward mechanism for signal integration coordinated...
L-arabinose inducible promoters are commonly used in gene expression analysis. However, nutrient source and availability also play a role biofilm formation; therefore, metabolism could impact development. In this study we examined the of on Salmonella enterica serovar Typhimurium (S. Typhimurium) formation. Using mutants impaired for transport L-arabinose, showed that negatively impacts S. formation vitro. When is abrogated, returned to baseline levels. without ability import extracellular...
The glutamate/aspartate transporter GLAST-1 is expressed in bone vivo and also exists as a splice variant (GLAST-1a) which exon 3 excluded. Since expression regulated response to osteogenic mechanical stimuli binding of glutamate receptors on osteoblasts increases osteoblast number activity vitro, control extracellular concentrations may be critical for balanced remodelling. To determine whether GLAST isoforms act regulate concentration we investigated their pattern or level responsive...
The Pel exopolysaccharide is one of the most mechanistically conserved and phylogenetically diverse bacterial biofilm matrix determinants. a major contributor to structural integrity
Chemotactic bacteria sense environmental changes via dedicated receptors that bind to extra- or intracellular cues and relay this signal ultimately alter direction of movement toward beneficial away from harmful environments. In complex environments, such as the rhizosphere, must be able integrate diverse cues. Azospirillum brasilense is a microaerophilic motile bacterium promotes growth cereals grains. Root surface colonization prerequisite for effects on plant but how A. navigates...
A novel Gram-stain-positive, coccus-shaped, obligately anaerobic bacterium was isolated from a faecal sample obtained an individual in traditional community located off the southern coast of Peru. Comparative 16S rRNA gene sequence analysis showed belonged to genus Peptoniphilus but no particular relationship with any species, demonstrating less than 91 % similarity all members genus. The major cellular fatty acids isolate were determined be C10 : 0, C14 C16 C18 1ω9c and 2ω6,9c/anteiso-C18...
Abstract Bacteria of the genus Azospirillum , including most comprehensively studied brasilense are non‐pathogenic soil bacteria that promote growth diverse plants, making them an attractive model to understand non‐symbiotic, beneficial plant‐bacteria associations. Research into physiology and genetics these organisms spans decades a range molecular tools protocols have been developed for allelic exchange mutagenesis, in trans expression genes, fusions reporter genes. © 2017 by John Wiley...
Bacterial chemotaxis, the ability of motile bacteria to navigate gradients chemicals, plays key roles in establishment various plant-microbe associations, including those that benefit plant growth and crop productivity. The soil bacterium Azospirillum brasilense colonizes rhizosphere promotes diverse plants across a range environments. Aerotaxis, or oxygen gradients, is widespread behavior bacteria. It one strongest behavioral responses A. it essential for successful colonization root...
Many bacterial species use the secondary messenger, c-di-GMP, to promote production of biofilm matrix components. In Pseudomonas aeruginosa, c-di-GMP is stimulated upon initial surface contact and generally remains high throughout growth. Transcription several gene clusters, including Sia signal transduction system, are induced in response cellular levels c-di-GMP. The output this system SiaD, a diguanylate cyclase whose activity presence detergent SDS. Previous studies demonstrated that...
Abstract Bacteria of the genus A. brasilense are motile and capable chemotaxis aerotaxis (taxis in gradient oxygen) using a single polar flagellum that propels cells aqueous environments. Responses to attractants repellents have been described spatial assays permit visualization these responses detailed this unit. These simple can be readily implemented with minimum set ups. © 2018 by John Wiley & Sons, Inc.