Bj. Beck et al., EVIDENCE THAT RSEC, A GENE IN THE RPOE CLUSTER, HAS A ROLE IN THIAMINE SYNTHESIS IN SALMONELLA-TYPHIMURIUM, Journal of bacteriology, 179(20), 1997, pp. 6504-6508
In Salmonella typhimurium, the genetic loci and biochemical reactions
necessary for the conversion of aminoimidazole ribotide (AIR) to the 4
-amino-5-hydroxymethyl-2-methyl pyrimidine (HMP) moiety of thiamine re
main unknown. Preliminary genetic analysis indicates that there may be
more than one pathway responsible for the synthesis of HMP from ATR a
nd that the function of these pathways depends on the availability of
UR, synthesized by the purine pathway or by the purF-independent alter
native pyrimidine biosynthetic (APE) pathway (L., Petersen and D. Down
s, J., Bacteriol. 178:5676-5682, 1996). An insertion in rseB, the thir
d gene in the rpoE rseABC gene cluster at 57 min, prevented HMP synthe
sis in a purl: mutant, Complementation analysis demonstrated that the
HMP requirement of the purF rseB strain was due to polarity of the ins
ertion in rseB on the downstream rseC gene. The role of RseC in thiami
ne synthesis was independent of rpoE.