Bacterial conjugation and Plasmid stabilisation

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Conjugation is a unidirectional DNA transfer process involving cell-cell contact. First, one DNA strand has to be nicked in a definite phosphodiester bond within the oriT (origin of transfer). This process is catalyzed by relaxases, enzymes that are encoded on conjugative plasmids and most mobilizable plasmids. pIP501 is an antibiotic-resistance plasmids, it was originally isolated from Streptococcus agalactiae and can be transferred by means of conjugation to a variety of pathogenic and apathogenic bacteria.
We work on crystallization and structural analysis of pIP501 relaxase TraA, and its N - terminal domain TraAs.

The project is carried out in collaboration with Institut für Ökologie der Mikroorganismen, TU-Berlin.

Related publications:
1) Grohmann, E.; Muth, G.; Espinosa, M. (2003). Conjugative Plasmid Transfer in Gram-Positive Bacteria. Microbiol. Mol. Biol. Rev. 67 (2): 277-301.
2) B. Kurenbach, C. Bohn, J. Prabhu, M. Abudukerim, U. Szewzyk, E.Grohmann. (2003). Intergeneric transfer of the Enterococcus faecalis plasmid pIP501 to Escherichia coli and Streptomyces lividans and sequence analysis of its tra region. Plasmid 50: 86-93.
3) Kurenbach, B.; Grothe, D.; Farias, M.E.; Szewzyk, U.; Grohmann, E. (2001). The tra region of the conjugative plasmid pIP501 is organized in an operon with the first gene encoding the relaxase. J. Bacteriol. 184:1801-1805.
4) Wang, A.; Macrina, F.L. (1995). Streptococcal plasmid pIP501 has a functional oriT site. J. Bacteriol. 177:4199-4206

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