A5046544300- Antibiotic Resistance in Bacteria
- Bacterial Genetics and Biotechnology
- Escherichia coli research studies
- Mycobacterium research and diagnosis
- Tuberculosis Research and Epidemiology
- Vibrio bacteria research studies
- Salmonella and Campylobacter epidemiology
- Helicobacter pylori-related gastroenterology studies
- Bacterial biofilms and quorum sensing
- Bacteriophages and microbial interactions
- Antibiotic Use and Resistance
- Clostridium difficile and Clostridium perfringens research
- Immune responses and vaccinations
- Gut microbiota and health
- Veterinary medicine and infectious diseases
- Viral gastroenteritis research and epidemiology
- Bacterial Identification and Susceptibility Testing
- Pneumonia and Respiratory Infections
- interferon and immune responses
- RNA modifications and cancer
- Viral Infections and Immunology Research
- RNA regulation and disease
- Clinical practice guidelines implementation
- Virus-based gene therapy research
- Cystic Fibrosis Research Advances
Instituto Politécnico Nacional
2016-2025
Mexican Social Security Institute
2014-2025
Centro Medico Nacional Siglo XXI
2016-2025
Hôpital Beau-Séjour
2015
Abstract Here, we conducted a comprehensive analysis of 356 Klebsiella pneumoniae species complex (KpSC) isolates that were classified as classical (cl), presumptive hypervirulent (p-hv) and hypermucoviscous-like (hmv-like). Overall, K. (82.3%), variicola (2.5%) quasipneumoniae identified. These comprised 321 cl-KpSC, 7 p-hv-KpSC 18 hmv-like-KpSC. A large proportion cl-KpSC extended-spectrum-β-lactamases (ESBLs)-producers (64.4%) 3.4% colistin-resistant carrying carbapenemase ESBL genes. All...
Klebsiella pneumoniae is an opportunistic pathogen causing nosocomial infections. Main virulence determinants of K. are pili, capsular polysaccharide, lipopolysaccharide and siderophores. The histone-like nucleoid-structuring protein (H-NS) a pleiotropic regulator found in several gram-negative pathogens. It has functions both as architectural component the nucleoid global gene expression. We generated Δhns mutant evaluated role H-NS on features pneumoniae. A down-regulated mrkA pilin...
Abstract Escherichia coli is a leading cause of invasive bacterial infections in humans. Capsule polysaccharide has an important role pathogenesis, and the K1 capsule been firmly established as one most potent types E. through its association with severe infections. However, little known about distribution, evolution functions across phylogeny, which fundamental to elucidating expansion successful lineages. Using systematic surveys isolates, we show that K1- cps locus present quarter...
Helicobacter pylori is a Gram-negative bacterium that colonizes the human gastric mucosa and causes peptic ulcers carcinoma. H. strain 26695 has small genome (1.67 Mb), which codes for few known transcriptional regulators control bacterial metabolism virulence. We analyzed by qRT-PCR expression of 16 in 26695, including three sigma factors under different environmental conditions. When bacteria were exposed to acidic pH, urea, nickel or iron, differentially expressed with particularly strong...
Enterobacter cloacae has emerged as an opportunistic pathogen in healthcare-associated infections. Analysis of the genomic sequences several E. strains revealed presence genes that code for expression at least one type VI secretion system (T6SS). Here, we report strain ATCC 13047 codes two functional T6SS named T6SS-1 and T6SS-2. T6SS-2 were preferentially expressed tryptic soy broth tissue culture medium (DMEM), respectively. Mutants T6SS-1-associated clpV1 hcp1 significantly affected their...
Klebsiella oxytoca toxigenic strains represent a critical health threat, mainly due to their link antibiotic-associated hemorrhagic colitis. This serious condition results from the bacteria’s ability produce tilimycin and tilivalline cytotoxins. Our research highlights pivotal role of OmpR, key regulator within EnvZ/OmpR two-component system, in controlling virulence factors associated with K. oxytoca. findings strongly indicate that OmpR is repressor aroX npsA genes, first genes NRPS...
Enterohemorrhagic Escherichia coli (EHEC) is a significant cause of serious human gastrointestinal disease worldwide. EHEC strains contain pathogenicity island called the locus enterocyte effacement (LEE), which encodes virulence factors responsible for damaging gut mucosa. The Cpx envelope stress response E. controlled by two-component system (TCS) consisting sensor histidine kinase (CpxA) and cytoplasmic regulator (CpxR). In this study, we investigated role CpxRA in expression LEE-encoded...
The capacity of Mycobacterium tuberculosis (Mtb) to sense, respond and adapt a variable hostile environment within the host has made it one most successful human pathogens. During different stages infection, Mtb is surrounded by plethora lipid rich molecules current evidence points out relevance fatty acids during infectious process. In this study, we have compared transcriptional response hypoxia in cultures grown both, mix either even long-chain or dextrose as carbon sources. Using RNA...
Hypermucoviscosity (hmv) is a capsule-associated phenotype usually linked with hypervirulent Klebsiella pneumoniae strains. The key components of this are the RmpADC proteins contained in non-transmissible plasmids identified and studied K. . variicola closely related to recently has been as an emergent human pathogen. variicol normally contains plasmids, some them carrying antibiotic resistance virulence genes. Previously, we described clinical isolate showing hmv-like that harbors 343-kb...
The genome of Mycobacterium tuberculosis (Mtb) harbors the genetic machinery for assembly Fimbrial low-molecular-weight protein (Flp) type IV pilus. Presumably, Flp pilus is essential pathogenesis. However, it remains unclear whether pili genes are transcribed in culture or during infection host cells. This study aimed to shed light on expression pili-assembly (tadZ, tadA, tadB, tadC, flp, tadE, and tadF) Mtb growing under different growth conditions (exponential phase, stationary dormancy...
Klebsiella pneumoniae is recognized as a common cause of nosocomial infections and outbreaks causing pneumonia, septicemia, urinary tract infections. This opportunistic bacterium shows an increasing acquisition antibiotic-resistance genes, which complicates treatment Hence, fast reliable strain typing methods are paramount for the study this pathogen’s multi-drug resistance genetic profiles. In study, thirty-eight strains K. isolated from blood pediatric patients were characterized by...
Helicobacter pylori is a Gram-negative bacterium that colonizes the human gastric mucosa and responsible for causing peptic ulcers carcinoma. The expression of virulence factors allows persistence H. in stomach, which results chronic, sometimes uncontrolled inflammatory response. Type II toxin-antitoxin systems have emerged as important many pathogenic bacteria. Three type (TA) previously been identified genome 26695: HP0315-HP0316, HP0892-HP0893, HP0894-HP0895. Here we characterized...
Avian pathogenic Escherichia coli (APEC) causes localized and systemic avian infections is responsible for considerable economic losses in the poultry industry. This organism adheres invades human cells, however, regulatory networks that dictate its virulence are largely unknown. The CpxRA two-component system sensing controlling outer-membrane stress detecting misfolded proteins bacterial periplasmic space. CpxA a membrane sensor kinase CpxR cytoplasmic transcriptional regulator. In this...
Klebsiella pneumoniae successfully colonizes host tissues by recognizing and interacting with cholesterol present on membrane-associated lipid rafts. In this study, we evaluated the role of in expression capsule polysaccharide genes K. its implication resistance to phagocytosis. Our data revealed that exogenous added increases macrophage-mediated To explain event, capsular galF, wzi manC was determined presence cholesterol. Down-regulation these occurred leading increased susceptibility...
Mycobacterium tuberculosis and M. smegmatis form drug-tolerant biofilms through dedicated genetic programs. In support of a stepwise process regulating biofilm production in mycobacteria, it was shown elsewhere that lsr2 participates intercellular aggregation, while groEL1 required for maturation smegmatis. Here, by means RNA-Seq, we monitored the early steps bovis BCG, to distinguish aggregation from attachment surface. Genes encoding transcriptional regulators dosR BCG0114 (Rv0081) were...
Abstract A single intradermal vaccination with an antibiotic-less version of BCGΔBCG1419c given to guinea pigs conferred a significant improvement in outcome following low dose aerosol exposure M. tuberculosis compared that provided by BCG Pasteur. was more attenuated than murine macrophages, athymic, BALB/c, and C57BL/6 mice. In pigs, at least as induced similar dermal reactivity BCG. Vaccination resulted increased anti-PPD IgG those receiving Guinea vaccinated showed reduction replication...
ABSTRACT The toxigenic Klebsiella oxytoca strains secret the tilivalline enterotoxin, which causes antibiotic-associated hemorrhagic colitis. is a non-ribosomal peptide synthesized by enzymes encoded in two divergent operons clustered pathogenicity island. transcriptional regulator Lrp ( l eucine-responsive r egulatory p rotein) controls expression of several bacterial genes involved virulence. In this work, we determined aroX and npsA , first each biosynthetic operon K. MIT 09-7231...
is an emerging pathogen isolated in healthcare-associated infections. A major virulence factor of this bacterium the type VI secretion system (T6SS). The genome
Carbapenem-resistant Pseudomonas aeruginosa is defined by the World Health Organization as a "high priority" in developing new antimicrobials. Indeed, emergence and spread of multidrug-resistant (MDR) or extensively drug-resistant (XDR) bacteria increase morbidity mortality risk infected patients. Genomic variants P. that display phenotypes MDR/XDR have been high-risk global clones. In this mini-review, we describe some international clones carry β-lactamase genes can produce chronic...
<b><i>Background:</i></b> Gram-negative bacilli are the most common bacteria causing nosocomial bloodstream infections (NBSIs) in Latin American countries. <b><i>Methods:</i></b> The antibiotic resistance profiles of isolated from blood cultures pediatric patients with NBSIs over a 3-year period tertiary care hospital Mexico City were determined using VITEK-2 system. Sixteen antibiotics tested to ascertain rate and minimum inhibitory...
Klebsiella pneumoniae is a common opportunistic pathogen causing nosocomial infections. One of the main virulence determinants K. type 3 pilus (T3P). T3P helps bacterial interaction to both abiotic and biotic surfaces it crucial for biofilm formation. genetically organized in three transcriptional units: mrkABCDF polycistronic operon, mrkHI bicistronic operon mrkJ gene. MrkH regulatory protein encoded which positively regulates mrkA pilin gene its own expression. In contrast, H-NS nucleoid...
Summary Enterotoxigenic Escherichia coli produces a long type 4 pilus called Longus. The regulatory elements and the environmental signals controlling expression of Longus‐encoding genes are unknown. We identified two lngR lngS in Longus operon, whose predicted products share homology with transcriptional regulators. Isogenic mutants were considerably affected transcription lngA pilin gene. lngA, was optimally expressed at 37°C pH 7.5. presence glucose sodium chloride had positive effect on...
Klebsiella oxytoca is a resident of the human gut. However, certain K. toxigenic strains exist that secrete nonribosomal peptide tilivalline (TV) cytotoxin. TV pyrrolobenzodiazepine causes antibiotic-associated hemorrhagic colitis (AAHC). The biosynthesis driven by enzymes encoded aroX and NRPS operons. In this study, we determined effect environmental signals such as carbon sources, osmolarity, divalent cations on transcription both biosynthetic Gene expression was enhanced when bacteria...