A5042924164- Escherichia coli research studies
- Antibiotic Resistance in Bacteria
- Gut microbiota and health
- Urinary Tract Infections Management
- SARS-CoV-2 and COVID-19 Research
- COVID-19 Clinical Research Studies
- Bacteriophages and microbial interactions
- Bacterial Genetics and Biotechnology
- Helicobacter pylori-related gastroenterology studies
- SARS-CoV-2 detection and testing
- Mycobacterium research and diagnosis
- Long-Term Effects of COVID-19
- Peptidase Inhibition and Analysis
- Cystic Fibrosis Research Advances
- Neonatal Respiratory Health Research
- Antimicrobial Peptides and Activities
- Respiratory viral infections research
- Nail Diseases and Treatments
- Pharmaceutical and Antibiotic Environmental Impacts
- Pancreatitis Pathology and Treatment
- Inflammasome and immune disorders
- Enterobacteriaceae and Cronobacter Research
- Tuberculosis Research and Epidemiology
- Celiac Disease Research and Management
- Blood Coagulation and Thrombosis Mechanisms
Murdoch Children's Research Institute
2019-2025
The University of Melbourne
2020-2025
The University of Queensland
2011-2024
Royal Children's Hospital
2019-2023
Queensland University of Technology
2016-2022
North Bengal Medical College and Hospital
2020
University of Michigan–Ann Arbor
2020
Australian Regenerative Medicine Institute
2020
Monash University
2020
<h3>Importance</h3> The immune response in children with SARS-CoV-2 infection is not well understood. <h3>Objective</h3> To compare seroconversion nonhospitalized and adults mild identify factors that are associated seroconversion. <h3>Design, Setting, Participants</h3> This household cohort study of collected weekly nasopharyngeal throat swabs blood samples during the acute (median, 7 days for 12 [IQR, 4-13] days) convalescent 41 31-49] periods after polymerase chain reaction (PCR)...
Escherichia coli strains causing urinary tract infection (UTI) are increasingly recognized as belonging to specific clones. E. clone O25b:H4-ST131 has recently emerged globally a leading multi-drug resistant pathogen and bloodstream infections in hospitals the community. While most molecular studies date examine mechanisms conferring resistance ST131, relatively little is known about their virulence potential. Here we examined ST131 clinical isolates from two geographically diverse...
Escherichia coli ST131 is a globally disseminated, multidrug resistant clone responsible for high proportion of urinary tract and bloodstream infections. The rapid emergence successful spread E. strongly associated with antibiotic resistance; however, this phenotype alone unlikely to explain its dominance amongst uropathogens circulating worldwide in hospitals the community. Thus, greater understanding molecular mechanisms that underpin fitness required. In study, we employed hyper-saturated...
Urinary tract infection (UTI) is one of the most common bacterial infections in humans, with uropathogenic Escherichia coli (UPEC) leading causative organism. UPEC has a number virulence factors that enable it to overcome host defenses within urinary and establish infection. The O antigen capsular polysaccharide are two such provide survival advantage UPEC. Here we describe application rpsL counter selection system construct capsule (kpsD) (waaL) mutants complemented derivatives three...
Compared to adults, children with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have predominantly mild or asymptomatic infections, but the underlying immunological differences remain unclear. Here, we describe clinical features, virology, longitudinal cellular, and cytokine immune profile, SARS-CoV-2-specific serology salivary antibody responses in a family of two parents PCR-confirmed symptomatic SARS-CoV-2 infection their three children, who tested repeatedly PCR negative....
Abstract Nitric oxide (NO) is a toxic free radical produced by neutrophils and macrophages in response to infection. Uropathogenic Escherichia coli (UPEC) induces variety of defence mechanisms NO, including direct NO detoxification (Hmp, NorVW, NrfA), iron-sulphur cluster repair (YtfE), the expression NO-tolerant cytochrome bd -I respiratory oxidase (CydAB). The current study quantifies relative contribution these systems UPEC growth survival during Loss flavohemoglobin Hmp elicit greatest...
Epidemiological studies point to the gut as a key reservoir of multidrug resistant Escherichia coli multilocus sequence type 131 (ST131), globally dominant pathogenic clone causing urinary tract and bloodstream infections. Here we report detailed investigation its intestinal lifestyle. Clinical ST131 isolates 1 fimbriae null mutants were assessed for colonization human epithelia in mouse models. Mouse tissue underwent histologic analysis pathology localization. Key findings corroborated...
Escherichia coli sequence type 131 (E. ST131) is a recently emerged and globally disseminated multidrug resistant clone associated with urinary tract bloodstream infections. Plasmids represent major vehicle for the carriage of antibiotic resistance genes in E. ST131. In this study, we determined complete performed comprehensive annotation pEC958, an IncF plasmid from ST131 reference strain EC958. Plasmid pEC958 135.6 kb size, harbours two replicons (RepFIA RepFII) contains 12 (including...
Background The most common cause of death in those with cystic fibrosis (CF) is respiratory failure due to bronchiectasis resulting from repeated cycles infection and inflammation. Protease-activated receptor 1 (PAR1) a cell surface activated by serine proteases including neutrophil elastase, which recognised as potent modulator While PAR1 known play an important role regulating inflammation, nothing about any potential this CF pathogenesis. Methods ( -/- ) intestinal-corrected CFTR Cftr...
Uropathogenic Escherichia coli (UPEC) is the leading causative agent of urinary tract infections (UTI) in developed world. Among major virulence factors UPEC, surface expressed adhesins mediate attachment and tissue tropism. UPEC strains typically possess a range adhesins, with type 1 fimbriae P chaperone-usher class best characterised. We previously identified characterised F9 as new fimbrial that mediates biofilm formation. However, regulation specific role remained to be determined...
ABSTRACT Escherichia coli sequence type 131 (ST131) is a clone of uropathogenic E. that has emerged rapidly and disseminated globally in both clinical community settings. Members the ST131 lineage from across globe have been comprehensively characterized terms antibiotic resistance, virulence potential, pathogenicity, but to date nothing known about methylome these important human pathogens. Here we used single-molecule real-time (SMRT) PacBio sequencing determine EC958,...
Escherichia coli sequence type 131 (ST131) has emerged as a pandemic lineage of important multidrug resistant pathogens worldwide. Despite many studies examining the epidemiology ST131, only few to date have investigated capacity ST131 strains form biofilms. Some these reported contrasting findings, with no specific biofilm-promoting factors identified. Here, we examined diverse collection isolates for in vitro biofilm formation different media and assay conditions, including urine from...
ABSTRACT Urinary tract infections (UTIs) are one of the most common bacterial in humans, with ~400 million cases across globe each year. Uropathogenic Escherichia coli (UPEC) is major cause UTI and increasingly associated antibiotic resistance. This scenario has been worsened by emergence spread pandemic UPEC sequence type 131 (ST131), a multidrug-resistant clone extraordinarily high rates infection. Here, we employed transposon-directed insertion site sequencing combination metabolomic...
Urinary tract infections (UTIs) are among the most common infectious diseases of humans, with Escherichia coli responsible for >80% all cases. One extreme UTI is asymptomatic bacteriuria (ABU), which occurs as an carrier state that resembles commensalism. To understand evolution and molecular mechanisms underpin ABU, genome ABU E. strain VR50 was sequenced. Analysis complete indicated it K-12, addition a 94-kb genomic island (GI-VR50-pheV), eight prophages, multiple plasmids. GI-VR50-pheV...
Uropathogenic Escherichia coli (UPEC) of sequence type 131 (ST131) are a pandemic multidrug resistant clone associated with urinary tract and bloodstream infections. Type 1 fimbriae, major UPEC virulence factor, essential for ST131 bladder colonization. The globally dominant sub-lineage strains, clade C/H30-R, possess an ISEc55 insertion in the fimB gene that controls phase-variable fimbriae expression via invertible fimS promoter. We report inactivation these strains causes altered...
Children have reduced severity of COVID-19 compared to adults and typically mild or asymptomatic disease. The immunological mechanisms underlying these age-related differences in clinical outcomes remain unexplained. Here, we quantify 23 immune cell populations 141 samples from children with their PCR-negative close household contacts at acute convalescent time points. displayed marked reductions myeloid cells during infection, most prominent under the age five. Recovery infection both was...
Household studies are crucial for understanding the transmission of SARS-CoV-2 infection, which may be underestimated from PCR testing respiratory samples alone. We aim to combine assessment household mitigation measures; nasopharyngeal, saliva, and stool testing; along with mucosal systemic SARS-CoV-2-specific antibodies, comprehensively characterize infection in households.
Abstract Objectives Escherichia coli ST131 is a globally disseminated MDR clone originally identified due to its association with the blaCTX-M-15 gene encoding an ESBL. It thus assumed that major determinant for resistance β-lactam antibiotics in this clone. The complete sequence of EC958, reference strain E. ST131, revealed it contains chromosomally located blaCMY-23 upstream ISEcp1 element as well several additional plasmid-encoded β-lactamase genes. Here, we examined genetic context EC958...
The binding of the type 1 fimbrial adhesin FimH to mannosylated receptors is allosterically regulated enhance fitness uropathogenic Escherichia coli (UPEC) during urinary tract infection (UTI). Mutations in two domains (pilin and lectin) located outside mannose pocket have been shown influence affinity, yet details allostery mechanism are not fully elucidated. Here we characterised different conformational states (termed low-affinity tense high-affinity relaxed conformations) natural...
Bacterial infection is one of the leading causes death in young, elderly, and immune-compromised patients. The rapid spread multi-drug-resistant (MDR) bacteria a global health emergency there lack new drugs to control MDR pathogens. We describe heretofore-unexplored discovery pathway for novel antibiotics that based on self-targeting, structure-disrupting peptides. show helical peptide, KFF-EcH3, derived from Escherichia coli methionine aminopeptidase can disrupt secondary tertiary structure...
Helicobacter pylori occupy a unique niche, located within the mucus layer lining stomach, and attached to apical surface of gastric epithelium. As such, antibodies would be expected play major role in regulating infection and/or pathogenesis. However, experiments using antibody-deficient mice study helicobacter have yielded inconsistent results, although some pointed toward increasing colonization levels decreasing gastritis severity. The variability these studies is possibly due their use...
Gastrokines (GKNs) are anti-inflammatory proteins secreted by gastric epithelial (surface mucous and pit) cells, with their aberrant loss of expression causally linked to premalignant inflammation cancer (GC). Transcriptional mechanisms accounting for GKN have not been elucidated. Using human clinical cohorts, mouse transgenics, bioinformatics, transfection/reporter assays, we report a novel mechanism gene transcriptional regulation its impairment in GC. GKN1/GKN2 is highly coordinated, both...
Abstract Importance The immune response in children with SARS-CoV-2 infection is not well understood. Objective To compare seroconversion and adults non-hospitalized (mild) to understand the factors that influence this. Design Participants were part of a household cohort study infection. Weekly nasopharyngeal/throat swabs blood samples collected during acute convalescent period following PCR diagnosis for analysis. Setting recruited at Royal Children’s Hospital, Melbourne, Australia between...