Open AccessStudies on the gene for the multivalent vitamin B 12 receptor of Escherichia coli
Author(s) -
Moir Peter D.,
Hunter Michael G.,
Armstrong John T.,
Glass Robert E.
Publication year - 1987
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1987.tb02178.x
Subject(s) - cistron , escherichia coli , plasmid , bacterial outer membrane , gene , biology , recombinant dna , gene product , microbiology and biotechnology , chemistry , gene expression , biochemistry
The Escherichia coli btuB cistron was identified in a λL47 gene bank constructed using chromosomal DNA from strain W3110. The product encoded by a multicopy recombinant plasmid was observed in the outer membrane, its presence leading to reduction in the amounts of 3 major outer membrane proteins. Analysis of the plasmid‐borne gene indicated that removal of the carboxy‐terminal region affected receptor function, without apparently preventing export to the outer membrane. Vitamin B 12 ‐dependent regulation of btuB expression was demonstrated, despite the gene being on a high copy number plasmid.