title: Plasmid-encoded ComI inhibits competence in the ancestral 3610 strain of Bacillus subtilis.
abstract: Natural competence is a process by which bacteria construct a membrane-associated machine for the uptake and integration of exogenous DNA. Many bacteria harbor genes for the DNA uptake machinery and yet are recalcitrant to DNA uptake for unknown reasons. For example, domesticated laboratory strains of Bacillus subtilis are renowned for high-frequency natural transformation, but the ancestral B. subtilis strain NCIB3610 is poorly competent. Here we find that endogenous plasmid pBS32 encodes a small protein, ComI, that inhibits transformation in the 3610 strain. ComI is a single-pass trans-membrane protein that appears to functionally inhibit the competence DNA uptake machinery. Functional inhibition of transformation may be common, and abolishing such inhibitors could be the key to permitting convenient genetic manipulation of a variety of industrially and medically relevant bacteria.
authors.affiliation: Indiana University, Department of Biology, Bloomington, IN, USA.
authors.forename: Melissa A
authors.initials: MA
authors.lastname: Konkol
authors.forename: Kris M
authors.initials: KM
authors.lastname: Blair
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Kearns
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism / Q000502:physiology; D001426:Bacterial Proteins / Q000235:genetics / Q000494:pharmacology*; D018441:Biofilms / Q000254:growth & development; D061269:DNA Transformation Competence / Q000187:drug effects*; D004269:DNA, Bacterial / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D008565:Membrane Proteins / Q000235:genetics / Q000494:pharmacology*; D010957:Plasmids / Q000235:genetics*; D016133:Polymerase Chain Reaction; D014169:Transformation, Bacterial / Q000187:drug effects
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D008565:Membrane Proteins