The lipid A biosynthesis deficiency of the Escherichia coli antibiotic-supersensitive mutant LH530 is suppressed by a novel locus, ORF195.
A new mutant of Escherichia coli K-12 supersensitive to both hydrophobic and large hydrophilic antibiotics was isolated and characterized. The mutant grew well at 28 degrees C, poorly at 37 degrees C, and did not grow at 42 degrees C. The rate of its lipid A biosynthesis was reduced as compared to that of the parent strain. This deficiency was rescued by a novel locus, ORF195, the function of which has not been elucidated. ORF195 is located in the 76 min region in the E. coli chromosome and encodes a hypothetical 21.8 kDa protein with no signal sequence. ORF195 isolated from the mutant strain had an identical sequence to the wild-type allele, indicating a suppressor function of the gene product.
Hirvas
Laura
L
Department of Bacteriology and Immunology, Haartman Institute,PO Box 21 (Haartmaninkatu 3), SF-00014 University of Helsinki, Helsinki,Finland.
Nurminen
Marjatta
M
Department of Bacteriology and Immunology, Haartman Institute,PO Box 21 (Haartmaninkatu 3), SF-00014 University of Helsinki, Helsinki,Finland.
Helander
Ilkka M
IM
Department of Bacterial Vaccine Research and Molecular Biology, National Public Health Institute,Mannerheimintie 166, FIN-00300 Helsinki,Finland.
Vuorio
Riitta
R
Department of Bacteriology and Immunology, Haartman Institute,PO Box 21 (Haartmaninkatu 3), SF-00014 University of Helsinki, Helsinki,Finland.
Vaara
Martti
M
Department of Bacteriology and Immunology, Haartman Institute,PO Box 21 (Haartmaninkatu 3), SF-00014 University of Helsinki, Helsinki,Finland.
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002463:Cell Membrane Permeability / Q000235:genetics; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development; D018628:Gene Dosage; D005798:Genes, Bacterial; D005816:Genetic Complementation Test; D008050:Lipid A / Q000096:biosynthesis*; D008070:Lipopolysaccharides / Q000096:biosynthesis; D008826:Microbial Sensitivity Tests; D016296:Mutagenesis; D016366:Open Reading Frames; D010641:Phenotype; D010743:Phospholipids / Q000096:biosynthesis; D017422:Sequence Analysis, DNA; D013489:Suppression, Genetic; D013696:Temperature
D000900:Anti-Bacterial Agents; D008050:Lipid A; D008070:Lipopolysaccharides; D010743:Phospholipids