Position effects on promoter activity inEscherichia coliand their consequences for antibiotic-resistance determinants

Abstract

The activity of any bacterial promoter is generally supposed to be set by its base sequence and the different transcription factors that bind in the local vicinity. Here, we review recent data indicating that the activity of the Escherichia coli lac operon promoter also depends upon its chromosomal location. Factors that affect promoter activity include the binding of nucleoid-associated proteins to neighbouring sequences, supercoiling and the activity of neighbouring promoters. We suggest that many bacterial promoters might be susceptible to similar position-dependent effects and we review recent data showing that the expression of mobile genes encoding antibiotic-resistance determinants is also location-dependent, both when carried on a bacterial chromosome or a conjugative plasmid.

Insulation of ribosomal promoter activity by Fis, H-NS or a divergent promoter within the packed E. coli genome.

“…Bacterial genomes evolve by both intragenomic and intergenomic, horizontal, gene transfer (73). Gene expression can be influenced by its position in the genome due to both local and genomic scale effects (5, 8, 31, 42, 43). Therefore, when a gene lands in a new position in the genome it will not necessarily be expressed in the same fashion as before (31, 38).…”

Physiological Robustness of Model Gram-Negative Bacteria in Response to Genome Rewiring

“…Microb Physiol 2022;32:158-176 DOI: 10.1159/000526651 2014; Brambilla and Sclavi, 2015;Gerganova et al, 2015;Frimodt-Møller et al, 2016;Inoue et al, 2016;Cooke et al, 2019]. For examples of these phenomena, see the section below on gene position and transcription output.…”

“…Experiments with hns promoter relocation show that local nucleoprotein structure plays a role, with segments of the chromosome that experience H-NS binding being nonpermissive for transcription [Brambilla and Sclavi, 2015]. The E. coli lac promoter also displays chromosome position-dependent variations in transcription output that are due to local nucleoprotein complexes [Bryant et al, 2014;Cooke et al, 2019]. These regions of the chromosome, called transcriptionally silent extended protein occupancy domains (tsEPODs), have an average length of 2 kilobases and are enriched in NAP binding [Vora et al, 2009].…”

Prevalence of Antibiotic Resistance and Its Challenges for Health Care Providers

“…Superbugs the antibiotic resistant organisms are the major concern. It is not just a concern related to laboratory although they have turn into a worldwide hazard accountable in favor of towering mortality as well as those of the infections which are lifethreatening in nature [43]. http://dx.doi.org/ More than 70,000 patients in (USA) the United States of Americaexpire almost every year as due to the hospital acquired infections of bacterial in nature.…”

“…Persons as well as states engage in recreation a responsibility in the development of antibiotic confrontation. For instance Clarithromycin use as well as its confrontation likewise augmented in Japan flanked by 1993 and 2000 in comparison to other countries [47] Resistance in the unethical use of antibiotics has crooked to the rigorous worldwide health disaster as well as the people have no knowledge about their consequences that it poses onto the personal level and community type of level [43].…”