A5060103682- Salmonella and Campylobacter epidemiology
- Bacterial Genetics and Biotechnology
- RNA and protein synthesis mechanisms
- Antibiotic Resistance in Bacteria
- Bacteriophages and microbial interactions
- Escherichia coli research studies
- Viral Infectious Diseases and Gene Expression in Insects
- Vibrio bacteria research studies
- Monoclonal and Polyclonal Antibodies Research
- Advanced Electron Microscopy Techniques and Applications
- CAR-T cell therapy research
- Genomics and Chromatin Dynamics
- DNA Repair Mechanisms
- Protein purification and stability
- Burkholderia infections and melioidosis
- Clostridium difficile and Clostridium perfringens research
- Transgenic Plants and Applications
- Viral gastroenteritis research and epidemiology
- Immune Cell Function and Interaction
- Toxin Mechanisms and Immunotoxins
- Advanced Fluorescence Microscopy Techniques
- Molecular Biology Techniques and Applications
- DNA and Nucleic Acid Chemistry
- RNA modifications and cancer
- Glycosylation and Glycoproteins Research
National Institutes of Health
2009-2020
National Cancer Institute
2009-2020
Center for Cancer Research
2018-2020
Frederick National Laboratory for Cancer Research
2009-2018
Massey University
2013
University of Auckland
2013
Infectiologie Animale et Santé Publique
2006-2007
Institut National de la Recherche Agronomique
2005
ABSTRACT CmeABC, a multidrug efflux pump, is involved in the resistance of Campylobacter jejuni to broad spectrum antimicrobial agents and essential for colonization animal intestine by mediating bile resistance. Previously, we have shown that expression this pump under control transcriptional repressor named CmeR. Inactivation CmeR or mutation cmeABC promoter (P ) region derepresses , leading overexpression pump. However, it unknown if can be conditionally induced substrates extrudes. In...
To fit within the confines of cell, bacterial chromosomes are highly condensed into a structure called nucleoid. Despite high degree compaction in nucleoid, genome remains accessible to essential biological processes, such as replication and transcription. Here, we present first high-resolution chromosome conformation capture-based molecular analysis spatial organization Escherichia coli nucleoid during rapid growth rich medium following an induced amino acid starvation that promotes...
In Escherichia coli the genome must be compacted approximately 1,000-fold to contained in a cellular structure termed nucleoid. It is proposed that of nucleoid determined by balance multiple compaction forces and one major expansion force. The latter mediated transertion, coupling transcription, translation, translocation nascent membrane proteins and/or exported proteins. supporting this notion, it has been shown consistently inhibition transertion translation inhibitor chloramphenicol...
Macrolide-resistant mutants of Campylobacter jejuni and coli were selected in vitro using erythromycin tylosin. These exhibited modifications the ribosomal proteins L4 (G74D) L22 (insertions at position 86 or 98). A synergy between CmeABC efflux pump these conferring macrolide resistance was observed.
Recent studies have shown that RNA polymerase (RNAP) is organized into distinct clusters in Escherichia coli and Bacillus subtilis cells. Spatially molecular components prokaryotic systems imply compartmentalization without the use of membranes, which may offer insights unique functions regulations. It has been proposed formation RNAP driven by active ribosomal (rRNA) transcription function as factories for highly efficient transcription. In this work, we examined these hypotheses...
This study was conducted to examine the role of CmeABC efflux pump in decreasing susceptibility Campylobacter coli macrolides and ketolides context absence or presence mutations 23S rRNA genes.The cmeB gene inactivated strains C. showing two different patterns erythromycin resistance (low high level resistance) associated with a A2075G mutation genes. MICs erythromycin, azithromycin, tylosin, telithromycin ciprofloxacin were compared for wild-type (with without inhibitor) mutant strains.The...
The thermodynamic association of RNA polymerase (RNAP) with DNA is sensitive to salt concentration in vitro. Paradoxically, previous studies changes osmolarity during steady-state cell growth found no dependence between the RNAP and K(+) Escherichia coli. We reevaluated this issue by following interaction genomic time-course experiments hyper-osmotic response. Our results show that temporally controlled same physical chemistry principle as rapidly dissociates from genome initial response...
Recombinant human interleukin-15 (IL-15) is a potent cancer immunotherapeutic candidate due to its excellent immune stimulating effects. Previous work demonstrated that IL-15 appeared with short half-life in circulation system, while the complex receptor can prolong as well benefit activities vivo. Therefore, was more favorably considered for clinical development. Herein we developed IL-15·sIL-15Rα/Fc, comprising of and extracellular region alpha subunit which fused Immunoglobulin G (IgG1)...
A multidrug-resistant mutant of Campylobacter jejuni was selected in vitro using increasing concentrations enrofloxacin. This accumulated less ethidium bromide than the parental strain, suggesting participation active efflux as a resistance mechanism. Inactivation cmeB gene confirmed and indicated involvement CmeABC pump multidrug mutant. Sequencing cmeR-cmeA intergenic region revealed point mutation binding site CmeR repressor. Transcriptional lacZ fusions showed an increase transcription...
In a fast-growing Escherichia coli cell, most RNA polymerase (RNAP) is allocated to rRNA synthesis forming transcription foci at clusters of rrn operons or bacterial nucleolus, and each the several nascent nucleoids contains multiple pairs replication forks. The composition has not been determined. addition, how machinery three-dimensionally organized promote cell growth in concord with nucleoid remains essentially unknown. Here, we determine spatial functional landscapes machineries E....
To engineer a host cell line that produces defucosylated mAbs with superior antibody‐dependent cellular cytotoxicity, we disrupted α‐1, 6 fucosyltransferase ( FUT8 ) gene in CHO‐S (CHO is Chinese hamster ovary) cells by clustered regularly interspaced short palindromic repeats‐CRISPR associated nuclease 9. The knockout was evaluated for growth, stability, and product quality. growth profile of −/− comparable wild type cells. catalyzes the transfer fucose residue from GDP‐fucose to N ‐glycans...
Objectives: This study was conducted to examine the genetic variation occurring in cmeB gene encoding transporter component of CmeABC efflux pump. Methods: Expression pump 21 strains Campylobacter jejuni and coli studied by western-blot analysis. MIC determination presence or absence an inhibitor (EPI). Inactivation sequencing cmeABC operon were performed for a single strain. The remaining compared RFLP analysis cmeB-specific PCR amplicon. genes two C. with different patterns sequenced...
RNA polymerase (RNAP), the transcription machinery, shows dynamic binding across genomic DNA under different growth conditions. The features that selectively redistribute limited RNAP molecules to dictate genome-wide in response environmental cues remain largely unknown. We chose bacterial osmotic stress model determine direct redistribution of during stress. Genomic mapping and transcriptome profiles corresponding temporal states after salt shock were determined. found rapid genome,...
Abstract Recent studies have shown that RNA polymerase (RNAP) is spatially organized into distinct clusters in E. coli and B. subtilis cells. Spatially molecular components prokaryotic systems imply compartmentalization without the use of membranes, which may offer new insights pertinent functions regulations. However, function RNAP whether its formation driven by active ribosomal (rRNA) transcription remain elusive. In this work, we investigated spatial organization cells using quantitative...
In comparison with full-length IgGs, antigen binding fragments (Fabs) are smaller in size and do not require the complexed post-translational modification. Therefore, Fab can be cost-effectively produced using an Escherichia coli (E. coli) expression system. However, disulfide-bonds containing exogenous protein, including Fab, tend to form insoluble inclusion bodies E. coli, which has been bottleneck for protein expressions this The secretory of proteins periplasm or extracellular medium...