title: The putative coupling protein TcpA interacts with other pCW3-encoded proteins to form an essential part of the conjugation complex.
abstract: Conjugative plasmids encode antibiotic resistance determinants or toxin genes in the anaerobic pathogen Clostridium perfringens. The paradigm conjugative plasmid in this bacterium is pCW3, a 47-kb tetracycline resistance plasmid that encodes the unique tcp transfer locus. The tcp locus consists of 11 genes, intP and tcpA-tcpJ, at least three of which, tcpA, tcpF, and tcpH, are essential for the conjugative transfer of pCW3. In this study we examined protein-protein interactions involving TcpA, the putative coupling protein. Use of a bacterial two-hybrid system identified interactions between TcpA and TcpC, TcpG, and TcpH. This analysis also demonstrated TcpA, TcpC, and TcpG self-interactions, which were confirmed by chemical cross-linking studies. Examination of a series of deletion and site-directed derivatives of TcpA identified the domains and motifs required for these interactions. Based on these results, we have constructed a model for this unique conjugative transfer apparatus.
authors.affiliation: Department of Microbiology, Monash University, Clayton, Victoria 3800, Australia.
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Steen
authors.forename: Trudi L
authors.initials: TL
authors.lastname: Bannam
authors.forename: Wee Lin
authors.initials: WL
authors.lastname: Teng
authors.forename: Rodney J
authors.initials: RJ
authors.lastname: Devenish
authors.forename: Julian I
authors.initials: JI
authors.lastname: Rood
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D003016:Clostridium perfringens / Q000502:physiology*; D003227:Conjugation, Genetic; D005810:Multigene Family; D016297:Mutagenesis, Site-Directed; D020125:Mutation, Missense; D011485:Protein Binding; D025941:Protein Interaction Mapping; D011815:R Factors; D017384:Sequence Deletion; D020798:Two-Hybrid System Techniques
chemical_list: D001426:Bacterial Proteins