Open AccessNovel Class of Mutations of pilS Mutants, Encoding Plasmid R64 Type IV Prepilin: Interface of PilS-PilV Interactions
Author(s) -
Eriko Shimoda,
Toshio Mutô,
Takayuki Horiuchi,
Nobuhisa Furuya,
Teruya Komano
Publication year - 2008
Publication title -
journal of bacteriology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.652
H-Index - 246
eISSN - 1067-8832
pISSN - 0021-9193
DOI - 10.1128/jb.01204-07
Subject(s) - pilin , pilus , biology , mutant , plasmid , mating type , genetics , gene , mutation , bacterial adhesin , biochemistry , microbiology and biotechnology , escherichia coli
The type IV pili of plasmid R64 belonging to the type IVB group are required only for liquid mating. They consist of the major and minor components PilS pilin and PilV adhesin, respectively. PilS pilin is first synthesized as a 22-kDa prepilin from thepilS gene and is then processed to a 19-kDa mature pilin by PilU prepilin peptidase. In a previous genetic analysis, we identified four classes of thepilS mutants (T. Horiuchi and T. Komano, J. Bacteriol.180: 4613-4620, 1998). The products of the class IpilS mutants were not processed by prepilin peptidase; the products of the class II mutants were not secreted; in the class III mutants type IV pili with reduced activities in liquid mating were produced; and in the class IV mutants type IV pili with normal activities were produced. Here, we describe a novel class, class V, ofpilS mutants. Mutations in thepilS gene at Gly-56 or Tyr-57 produced type IV pili lacking PilV adhesin, which were inactive in liquid mating. Residues 56 and 57 of PilS pilin are suggested to function as an interface of PilS-PilV interactions.