• Korean Journal of Microbiology
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• v.27 no.3
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• pp.201-209
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• 1989

Using Mu dJ(Km lac) operon fusion, several oxygen-regulated genetic loci were identified in Salmonella typhimurium. Nine aerobically inducible(oxi) and thirteen anaerobically inducible(ani) operon fusions were newly identified. Based on the control by oxrA regulatory locus, the ani-lacZ fusions were grouped into two classes: class I loci were regulated by oxrA regulatory locus; class II genes were not affected by this locus. Some of the ani-lacZ fusions had required growth in CAA and LB before they exhibited the inducible phinotype. Most of all ani-lacZ fusions were repressed by nitrate and fumarate. Three of the ani loci were mapped into $59{\pm}0.14$ map unit (YK114), $64{\pm}0.5$ map unit(YK120), and $93{\pm}0.29$ map unit(YK112) by testing the cotransduction frequency, respectively.

• Korean Journal of Microbiology
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• v.30 no.5
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• pp.347-354
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• 1992

New regulatory, loci which participate in the regulation of anaerobic inducible gene expression in Salmonella typhimurium were identified. We observed the regulatory network of new regulator mutations to various anaerobic inducible gene (1). Some anaerobic inducible lac fusions were also induced at low pH condition which was severe environment to withstand for its virulence at the place like phagolysosome. Sic oxygen-regulated regulatory mutants (oxr) isolated by Tn10 mutagenesis were divided into two groups. Five of them were found to show negative effect on the regulation of anaerobic gene expression, while on e showed positive effect on the regulation. Genetic loci of four oxr were identified with 54 Mud-P22 lysogens covering the whole chromosome of S. typhimurium, in the nearby region of map unit 87 min (oxr101), 63 min (oxr104), 97 min (oxr 105), and 57 min (oxr 106), respectively. Two oxr mutants were subjected to two-dimensional polyacrylamide electrophoretic analysis of anaerobic inducible proteins for searching the control circuitry of our oxr mutants.