Cloning and sequence analysis of an Escherichia coli gene conferring bicyclomycin resistance.
We have cloned and sequenced DNA from Escherichia coli that, when present in a high-copy-number plasmid, confers resistance to the diketopiperazine antibiotic, bicyclomycin (Bc). The DNA includes a 378-amino-acid open reading frame (ORF), disruption of which results in the loss of Bc resistance. This ORF contains the BcR gene. Studies using the minicell expression system reveal that a polypeptide of 31 kDa is produced from this cloned region. The ORF maps at 47.1 min on the E. coli genome map. Sequence comparison between the translated ORF and a protein database reveal between 26.5 and 23.4% aa sequence homology to bacterial transmembrane (TM) proteins including those mediating chloramphenicol (Cm) and tetracycline (Tc) resistance and an arabinose-proton symport protein. Sequence analysis using the Diagon program showed the BcR gene product (BcR) had homology with the N-terminal regions of the CmR and TcR-encoded proteins and weak N-terminal homology with the arabinose-proton symport protein. Hydropathy profiles of the BcR protein and CmR products show a striking similarity, both having twelve predicted TM domains.
Bentley
J
J
Department of Biochemistry and Molecular Biology, University of Leeds, UK.
Hyatt
L S
LS
Ainley
K
K
Parish
J H
JH
Herbert
R B
RB
White
G R
GR
D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001483:Base Sequence; D001643:Bridged Bicyclo Compounds / Q000494:pharmacology; D019086:Bridged Bicyclo Compounds, Heterocyclic; D003001:Cloning, Molecular; D004269:DNA, Bacterial; D004352:Drug Resistance, Microbial / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D015183:Restriction Mapping; D017386:Sequence Homology, Amino Acid
D000900:Anti-Bacterial Agents; D001643:Bridged Bicyclo Compounds; D019086:Bridged Bicyclo Compounds, Heterocyclic; D004269:DNA, Bacterial; C024504:bicozamycin