Work

Acquisition of resistance genes by the IncQ plasmid R1162 is limited by its high copy number and lack of a partitioning mechanism

Year: 1997

Type: article

Abstract: R1162 is a representative member of the broad-host-range IncQ group of multicopy plasmids. Lower-copy-number derivatives of R1162 were constructed in vitro and shown to be unstable, indicating that partitioning of plasmid copies at cell division is due to random distribution and not to an active partitioning mechanism. However, the normal copy number of R1162 reduces cell fitness during growth in broth and favors the emergence of unstable, lower-copy-number variants. As a result, plasmid-borne antibiotic resistance genes active at a low copy number eventually result in plasmid loss during periods of no selection. We argue that the maintenance of R1162 in a population requires a gene that is selected only at high levels. This reduces the potential for acquiring genes from other R factors and could explain the limited variety of antibiotic resistance genes contained by naturally occurring IncQ plasmids.

Source: Journal of Bacteriology

DOI: 10.1128/jb.179.18.5947-5950.1997

Authors: E C Becker, R J Meyer

Institution: The University of Texas at Austin

Language: English

Topic: Bacterial Genetics and Biotechnology

Subfield: Genetics

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: green

Funder: National Institute of General Medical Sciences

Awards: CONJUGATIVE MOBILIZATION OF PLASMID R1162, G321530036