Amplification of the bacA gene confers bacitracin resistance to Escherichia coli.
An Escherichia coli genomic library was constructed in order to facilitate selection for genes which confer bacitracin resistance through amplification. One of the plasmids from the library, plasmid pXV62, provided a high level of bacitracin resistance for E. coli. Deletion and nucleotide sequence analyses of bacitracin resistance plasmid pXV62 revealed that a single open reading frame, designated the bacA gene, was sufficient for antibiotic resistance. The bacA gene mapped to approximately 67 min on the E. coli chromosome by proximity to a previously mapped locus. The deduced amino acid sequence of the bacA-encoded protein suggests an extremely hydrophobic protein of 151 amino acids, approximately 65% of which were nonpolar amino acids. E. coli cells containing plasmid pXV62 have increased isoprenol kinase activity. The physical characteristics of the deduced protein and enhanced lipid kinase activity suggest that the bacA gene may confer resistance to bacitracin by phosphorylation of undecaprenol.
Cain
B D
BD
Department of Biochemistry and Molecular Biology, University of Florida, Gainesville 32610.
Norton
P J
PJ
Eubanks
W
W
Nick
H S
HS
Allen
C M
CM
D000595:Amino Acid Sequence; D001414:Bacitracin / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000737:chemistry; D001483:Base Sequence; D002874:Chromosome Mapping; D004269:DNA, Bacterial / Q000235:genetics; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics*; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D010770:Phosphotransferases / Q000235:genetics* / Q000378:metabolism; D017853:Phosphotransferases (Alcohol Group Acceptor); D010957:Plasmids; D015183:Restriction Mapping; D012995:Solubility
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D001414:Bacitracin; D010770:Phosphotransferases; D017853:Phosphotransferases (Alcohol Group Acceptor); C021454:undecaprenol kinase