The Effect of Heavy Metals on Conjugation Efficiency of an F-Plasmid in Escherichia coli

Abstract

Conjugation, the process by which conjugative plasmids are transferred between bacteria, is regarded as a major contributor to the spread of antibiotic resistance, in both environmental and clinical settings. Heavy metals are known to co-select for antibiotic resistance, but the impact of the presence of these metals on conjugation itself is not clear. Here, we systematically investigate the impact that five heavy metals (arsenic, cadmium, copper, manganese, and zinc) have on the transfer of an IncF conjugative plasmid in Escherichia coli. Our results show that two of the metals, cadmium and manganese, have no significant impact, while arsenic and zinc both reduce conjugation efficiency by approximately 2-fold. Copper showed the largest impact, with an almost 100-fold decrease in conjugation efficiency. This was not mediated by any change in transcription from the major Py promoter responsible for transcription of the conjugation machinery genes. Further, we show that in order to have this severe impact on the transfer of the plasmid, copper sulfate needs to be present during the mating process, and we suggest explanations for this.

Thiophene-Derived Schiff Base Complexes: Synthesis, Characterization, Antimicrobial Properties, and Molecular Docking

“…It rapidly localized intracellularly, especially in the liver, binding to metallo-thionein to form a complex that is slowly transferred to the bloodstream to be deposited in the kidneys. However, recent studies have demonstrated a wide range of pharmacological properties of cadmium complexes with sulfur-derived ligands …”

“…However, recent studies have demonstrated a wide range of pharmacological properties of cadmium complexes with sulfur-derived ligands. 51 …”

Pyridine‐derived Schiff base copper (II), zinc (II), and cadmium (II) complexes: Synthesis, structural properties, biological evaluation, and docking studies

“…The complexes penetrate into the lipid membrane and the blockage of metal binding sites in the enzymes of microorganisms might inhibit their action 59,79 . Since many heavy metals exhibited toxicity to microbes as they bind to intracellular proteins and lead to inactivate them, 80 however, the attachment of metal has a pronounced effect on the leishmanicidal potential of the ligand as well as the metal salts alone. As shown in Table 3, the metal salts have shown lower leishmanicidal potential and resulted in an enhanced inhibitory profile upon chelation to DEP.…”

Pharmaceuticals and Personal Care Products in the Environment with Emphasis on Horizontal Transfer of Antibiotic Resistance Genes

“…Nowadays, nanoparticles are widely used in the industry, and they are leached into the wastewater and could reach water bodies raising the concern to the contamination issues [51]. In addition to nanoparticles heavy metal pollutants in wastewaters such as mercury, cadmium, arsenic play a role in increasing the ARG by HGT [50][51][52][53]. The metals make the bacterial membrane leaky, increase the expression of genes that can increase conjugation and DNA replication process that helps in the formation of conjugation tube between the donor and recipient bacteria.…”