RRC ID 30047
著者 Chang YY, Cronan JE Jr.
タイトル Mapping nonselectable genes of Escherichia coli by using transposon Tn10: location of a gene affecting pyruvate oxidase.
ジャーナル J Bacteriol
Abstract Mutants of Escherichia coli K-12 deficient in pyruvate oxidase were isolated by screening for the production of 14CO2 from [1-14C]pyruvate by the method of Tabor et al. (J. Bacteriol. 128:485-486, 1976). One of these lesions (designated poxA) decreased the pyruvate oxidase activity to 10 to 15% of the normal level but grew well. To map this nonselectable mutation, we isolated strains having transposon Tn10 inserted into the chromosome close to the poxA locus and mapped the transposon. These insertions were isolated by the following procedure: (i) pools of Tn10 insertions into the chromosomes of two different Hfr strains were prepared by transposition from a lambda::Tn10 vector; (ii) these Tn10-carrying strains were then mated with a poxA recipient strain, and tetracycline-resistant (Tetr) recombinants were selected; (iii) the Tetr recombinants were then screened for 14CO2 production from [1-14C]pyruvate. This method was shown to give a greater than 40-fold enrichment of insertions of Tn10 near the poxA gene as compared with transduction. Calculations indicate that a similar enrichment should be expected for other genes. The enrichment is due to the much greater map interval over which strong linkage between selected and unselected markers is found in conjugational crosses as compared with transductional crosses. The use of Hfr conjugative transfer allows isolation of transposon insertions closely linked to a nonselectable gene by scoring hundreds rather than thousands of colonies. Using a Tn10 insertion greater than 98% cotransduced with the poxA locus, we mapped the poxA gene on the E. coli genetic map. The poxA locus is located at 94 min, close to the psd locus. The clockwise gene order is ampA, poxA, psd, purA. The poxA mutation is recessive and appears to be a regulatory gene.
巻・号 151(3)
ページ 1279-89
公開日 1982-9-1
DOI 10.1128/jb.151.3.1279-1289.1982
PMID 6286595
PMC PMC220406
MeSH Chromosome Mapping Chromosomes, Bacterial* DNA Transposable Elements* Escherichia coli / enzymology Escherichia coli / genetics* Genes, Bacterial* Genes, Regulator Genetic Linkage Mutation Pyruvate Oxidase / genetics* Transduction, Genetic
IF 3.006
引用数 61
WOS 分野 MICROBIOLOGY
リソース情報
原核生物(大腸菌) ME8491 ME8489 ME8490