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Updated: Sep 7, 2025
07:11
Homemade Site Directed Mutagenesis of Whole Plasmids
Published on: May 11, 2009
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Host cell RecA activates a mobile element-encoded mutagenic DNA polymerase.
Debika Ojha1, Malgorzata M Jaszczur1, Adhirath Sikand2
1Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA.
Nucleic Acids Research
|June 23, 2022
Summary
Mobile element-encoded DNA polymerase V (pol V) requires host RecA protein to form a functional mutasome complex. This interaction influences polymerase activity and mutagenesis rates, potentially driving bacterial adaptation and antibiotic resistance.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Homologs of mutagenic Escherichia coli DNA polymerase V (pol V) are found in pathogens and mobile genetic elements.
- Mobile element-encoded polymerases (MEPols) can transfer between species, raising questions about their functional requirements in new hosts.
Purpose of the Study:
- To investigate the functional requirements of Rum pol (RumA'2B), a model MEPol from the integrative conjugative element R391.
- To determine if Rum pol requires host factors for its biochemical activity and mutagenic potential.
Main Methods:
- Biochemical assays were used to study the activity of Rum pol in vitro.
- Mutagenesis rates were measured in vivo in recipient bacteria.
- The role of RecA protein from various bacterial hosts was investigated.
Main Results:
- Rum pol biochemical activity necessitates the formation of a mutasomal complex (Rum Mut) involving RumA'2B, RecA, and ATP.
- RecA protein is supplied by the recipient bacterium.
- The specific activity of Rum Mut and in vivo mutagenesis rates are influenced by the phylogenetic distance between host RecA and E. coli RecA.
Conclusions:
- Rum pol functions as a mobile catalyst of evolution, requiring host RecA for activity.
- The dependence on host RecA suggests a mechanism for adapting to diverse bacterial environments.
- This mobile polymerase can generate a broad mutational landscape, potentially facilitating bacterial adaptation and the emergence of antibiotic resistance.
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