A5081453369- Clostridium difficile and Clostridium perfringens research
- Antimicrobial Resistance in Staphylococcus
- Helicobacter pylori-related gastroenterology studies
- Antibiotic Resistance in Bacteria
- Microscopic Colitis
- Gut microbiota and health
- Viral gastroenteritis research and epidemiology
- Tuberculosis Research and Epidemiology
- Cancer therapeutics and mechanisms
- Nosocomial Infections in ICU
- Synthesis and biological activity
- Bacterial Identification and Susceptibility Testing
- Pneumocystis jirovecii pneumonia detection and treatment
- Pharmacological Effects of Natural Compounds
- RNA and protein synthesis mechanisms
- Bacterial biofilms and quorum sensing
- Antibiotics Pharmacokinetics and Efficacy
- Pneumonia and Respiratory Infections
- Mycobacterium research and diagnosis
- Antimicrobial Peptides and Activities
- Bacterial Genetics and Biotechnology
- Microbial Natural Products and Biosynthesis
- Gastrointestinal motility and disorders
- Probiotics and Fermented Foods
- Herbal Medicine Research Studies
Texas A&M Health Science Center
2016-2025
Texas A&M University
2017
The University of Texas at Arlington
2010-2016
St. Jude Children's Research Hospital
2011-2014
University of Tennessee Health Science Center
2008-2009
University of Leeds
2003-2005
Severe outbreaks and deaths have been linked to the emergence global spread of fluoroquinolone-resistant Clostridioides difficile over past two decades. At same time, metronidazole, a nitro-containing antibiotic, has shown decreasing clinical efficacy in treating C. infection (CDI). Most metronidazole-resistant exhibit an unusual resistance phenotype that can only be detected susceptibility tests using molecularly intact heme. Here, we describe mechanism underlying this trait. We find most...
Epidemiologic studies have shown decreasing vancomycin susceptibility among clinical Clostridioides difficile isolates, but the impact on patient outcomes is unknown. We hypothesized that reduced would be associated with decreased rates of sustained response (SCR).
Nitrofuranylamides (NFAs) are nitroaromatic compounds that have recently been discovered and potent anti-tuberculosis (TB) activity. A foundational study was performed to evaluate whether this class of agents possesses microbiological properties suitable for future antimycobacterial therapy.Five representative the NFA series were evaluated by standard assays determine MICs, MBCs, activity against anaerobic non-replicating persistent Mycobacterium tuberculosis, post-antibiotic effects (PAEs),...
On the basis of recently reported abyssinone II and olympicin A, a series chemically modified flavonoid phytochemicals were synthesized evaluated against Mycobacterium tuberculosis panel Gram-positive -negative bacterial pathogens. Some compounds exhibited good antibacterial activities pathogens including methicillin resistant Staphylococcus aureus with minimum inhibitory concentration as low 0.39 μg/mL. SAR analysis revealed that 2-hydrophobic substituent 4-hydrogen bond donor/acceptor...
To describe, for the first time (to best of our knowledge), genetic mechanisms vancomycin resistance in clinical isolates Clostridioides difficile ribotype 027.
Objectives: We examined the molecular basis of emergence mupirocin resistance in a methicillin-resistant Staphylococcus aureus (MRSA) strain colonizing nursing home resident undergoing prophylaxis.
Dihydropteroate synthase (DHPS) is a key enzyme in bacterial folate synthesis and the target of sulfonamide class antibacterials. Resistance toxicities associated with sulfonamides have led to decrease their clinical use. Compounds that bind pterin binding site DHPS, as opposed p-amino benzoic acid (pABA) targeted by agents, are anticipated bypass resistance. To identify such inhibitors map pocket, we performed virtual screening, synthetic, structural studies using Bacillus anthracis DHPS....
Bacillus species are Gram-positive bacteria found in abundance nature and their secondary metabolites were to possess various potential activities, notably antimicrobial. In this study, amyloliquefaciens N2-4 N3-8 isolated from soil could kill Burkholderia pseudomallei, a Gram-negative pathogenic bacterium also its endemic areas. Moreover, the able drug resistant isolates of B. pseudomallei inhibit other such as Staphylococcus aureus, Escherichia coli Acinetobacter baumannii but not...
ABSTRACT Chromosomal resistance to mupirocin in clinical isolates of Staphylococcus aureus arises from V 588 F or 631 mutations isoleucyl-tRNA synthetase (IRS). Whether these are the only IRS that confer simply those survive clinic is unknown. Mupirocin-resistant mutants S. 8325-4 were therefore generated examine their ileS genotypes and vitro vivo fitness costs associated with them before after compensatory evolution. Most spontaneous first-step mupirocin-resistant carried IRS, but a new...
Chromosomal resistance to metronidazole has emerged in clinical Clostridioides difficile isolates, but the genetic mechanisms remain unclear. This is further hindered by inability generate spontaneous metronidazole-resistant mutants lab interpret variations isolates. We therefore constructed a mismatch repair mutator nontoxigenic ATCC 700057 survey mutational landscape for de novo mechanisms. In separate experimental evolutions, adopted deterministic path resistance, with truncation of...
Clinical studies have demonstrated inferior cure rates when metronidazole (MTZ) is used to treat
Objectives: We sought to investigate the anti-staphylococcal activity of indolmycin, with particular emphasis on comparing its fusidic acid and mupirocin. Methods: Established procedures were used examine indolmycin against a range clinical isolates, including strains resistant Indolmycin-resistant mutants recovered characterized phenotypically genotypically. Results: Indolmycin was bacteriostatic demonstrated good MSSA (methicillin-susceptible Staphylococcus aureus), MRSA...
Lead on! In the course of screening flavonoid and resveratrol libraries, abyssinone II, a naturally occurring prenylated flavonoid, was found to exhibit relatively good antitubercular antibacterial activity. Preliminary mechanistic studies revealed that II hyperpolarizes bacterial membrane potential inhibits biosynthesis key cellular macromolecules (DNA, RNA, protein).
Surotomycin (CB-183,315), a cyclic lipopeptide, is in phase 3 clinical development for the treatment of Clostridium difficile infection. We report here further characterization vitro mode action surotomycin, including its activity against growing and nongrowing C. difficile. This was assessed through time-kill kinetics, allowing determination effects on membrane potential permeability macromolecular synthesis Against representative strains difficile, surotomycin displayed...
Clostridium difficile infection (CDI) is an antibiotic-induced microbiota shift disease of the large bowel. While there a need for narrow-spectrum CDI antibiotics, it unclear which cellular proteins are appropriate drug targets to specifically inhibit C. difficile. We evaluated enoyl-acyl carrier protein (ACP) reductase II (FabK), catalyzes final step bacterial fatty acid biosynthesis. Bioinformatics showed that uses FabK as its sole enoyl-ACP reductase, unlike several major species. The...
Metronidazole resistance in clinical Clostridioides difficile is often described as unstable, since resistant strains reportedly appear susceptible following freezer storage or brief passage. This has presented a conundrum for adopting susceptibility testing to accurately evaluate the connection between metronidazole and decreased efficacy of patients with C. infections (CDIs). We discovered that supplementation microbiological media metalloporphyrin heme crucial detection...
ABSTRACT Ibezapolstat (IBZ), a first-in-class antibiotic targeting the PolC-type DNA polymerase III alpha-subunit (PolC) in low G + C bacteria, is clinical development for treatment of Clostridioides difficile infection (CDI). In phase 2 trials, IBZ had potent activity against C. while sparing or causing regrowth Lachnospiraceae, Oscillospiraceae, and Erysipelotrichales, common commensal bacteria. The purpose this study was to utilize silico approaches better interpret narrower than expected...