Propanediol utilization genes (pdu) of Salmonella typhimurium: Three genes for the propanediol dehydratase

摘要: The propanediol utilization (pdu) operon of Salmonella typhimurium encodes proteins required for the catabolism propanediol, including a coenzyme B12-dependent dehydratase. A clone that expresses dehydratase activity was isolated from genomic library. DNA sequence analysis showed included part pduF gene, pduABCDE genes, and long partial open reading frame (ORF1). 3.9 kbp pdu which had not been previously sequenced. Complementation expression studies with subclones constructed via PCR three genes (pduCDE) are necessary sufficient activity. function ORF1 determined. Analyses S. related to glycerol dehydratases Citrobacter freundii Klebsiella pneumoniae. Unexpectedly, found be 98% identical in amino acid oxytoca dehydratase; this is much higher identity than expected, given relationship between these organisms. analyses also supported previous indicating inherited along adjacent cobalamin biosynthesis by single horizontal gene transfer.