Original scientific paper
Genetic Requirements for Conjugational Recombination in the Presence of λ Gam Protein in Escherichia coli
Ivana Ivančić-Baće
; Department of Molecular Biology, Faculty of Natural Sciences, Rooseveltov trg 6, HR-10000 Zagreb, Croatia
Nikolina Škrobot
; Department of Molecular Biology, Faculty of Natural Sciences, Rooseveltov trg 6, HR-10000 Zagreb, Croatia
Davor Zahradka
; Department of Molecular Genetics, Ru|er Bo{kovi} Institute, Bijeni~ka 54, P. O. Box 180, HR-10002 Zagreb, Croatia
Erika Salaj-Šmic
; Department of Molecular Genetics, Ru|er Bo{kovi} Institute, Bijeni~ka 54, P. O. Box 180, HR-10002 Zagreb, Croatia
Krunoslav Brčić-Kostić
; Department of Molecular Genetics, Ru|er Bo{kovi} Institute, Bijeni~ka 54, P. O. Box 180, HR-10002 Zagreb, Croatia
Abstract
The Gam protein of phage is a well-known inhibitor of the enzymatic activities of the RecBCD enzyme, the major enzyme involved in homologous recombination in bacteria Escherichia coli. In this work, we studied (i) the effect of the RecA loading-deficient recB (recBD1080A) mutation on conjugational recombination in the presence of phage Gam protein and (ii) additional genetic requirements for the RecBCD-Gam-mediated conjugational recombination. For this purpose, we introduced Gam+ and Gam- expressing plasmids into wild type cells and different mutants of E. coli (recJ, recBD1080A, recB, recN, recF, recR, recO, recD), and determined the yields of recombinants after Hfr mediated conjugation. The obtained results suggest that RecA loading activity is not inhibited by Gam and that conjugational recombination in the presence of Gam is partially dependent on recJ and recO gene products.
Keywords
Escherichia coli; phage λ; conjugational recombination; RecBCD enzyme; Gam protein
Hrčak ID:
178519
URI
Publication date:
12.12.2002.
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