Con ⁻ Mutants: Class of Mutants in Escherichia coli K-12 Lacking a Major Cell Wall Protein and Defective in Conjugation and Adsorption of a Bacteriophage

Abstract

We describe a new class of mutants of Escherichia coli K-12 defective in conjugation (Con-mutants). They lack a major protein of the outer membrane and are defective as recipients with Hfr and F' donors and as recipients for several F-like R factors and Col factors. In the case of crosses with an Hfr donor, we have shown that the Conrecipient is defective in pair formation. The mutants are resistant to certain phages due to loss of receptor activity.

Identification of host genes that affect acquisition of an integrative and conjugative element in Bacillus subtilis

“…For example, in Enterococcus faecalis, potential recipients secrete signalling peptides that induce conjugation of certain plasmids (Dunny et al, 1978;Dunny, 2013). Studies with Escherichia coli, Salmonella typhimurium and E. faecalis identified surface components of the recipient that facilitate formation of mating pairs and contribute to conjugation (Watanabe et al, 1970;Skurray et al, 1974;Havekes et al, 1977;Sanderson et al, 1981;Trotter and Dunny, 1990;Ishiwa and Komano, 2004;Perez-Mendoza and de la Cruz, 2009).…”

Outer membrane protein 3B of Escherichia coli K-12: Effects of growth temperature on the amount of the protein and further characterization on acrylamide gels

“…In this paper, we identify protein 3B by using an ompB mutant, lacking protein 1 (J.K. Davies, Ph.D. Thesis, 1974, Univ. of Adelaide; Sarma and Reeves, manuscript in preparation); an ompA mutant, lacking protein 3A [9][10][11] ; and a tsx mutant lacking the tsx protein [6], in addition to the parent strain P400.…”

Studies on two major contaminating proteins of the cytoplasmic inclusion bodies in Escherichia coli

“…The outer membrane of E. coli contains ompA protein, ompC protein, ompF protein and Braun's lipoprotein as major proteins [17,18]. The ompA protein, a trans-membrane protein [19], has several nonphysiological and physiological functions [20][21][22][23][24][25][26]. The complete gene sequence [27,28] and protein sequence [14] of these proteins are already established.…”