Previous Article | Next Article ![]()
J. Bacteriol., Aug 1995, 4392-4401, Vol 177, No. 15
R Daniel, K Stuertz and G Gottschalk
Glycerol dehydrogenase (EC 1.1.1.6) and dihydroxyacetone kinase (EC
2.7.1.29) were purified from Citrobacter freundii. The dehydrogenase is a
hexamer of a polypeptide of 43,000 Da. The enzyme exhibited a rather broad
substrate specificity, but glycerol was the preferred substrate in the
physiological direction. The apparent Kms of the enzyme for glycerol and
NAD+ were 1.27 mM and 57 microM, respectively. The kinase is a dimer of a
polypeptide of 57,000 Da. The enzyme was highly specific for the substrates
dihydroxyacetone and ATP; the apparent Kms were 30 and 70 microM,
respectively. The DNA region which contained the genes encoding glycerol
dehydrogenase (dhaD) and dihydroxyacetone kinase (dhaK) was cloned and
sequenced. Both genes were identified by N- terminal sequence comparison.
The deduced dhaD gene product (365 amino acids) exhibited high degrees of
homology to glycerol dehydrogenases from other organisms and less homology
to type III alcohol dehydrogenases, whereas the dhaK gene product (552
amino acids) revealed no significant homology to any other protein in the
databases. A large gene (dhaR) of 1,929 bp was found downstream from dhaD.
The deduced gene product (641 amino acids) showed significant similarities
to members of the sigma 54 bacterial enhancer-binding protein family.
Copyright © 1995, American Society for Microbiology
Biochemical and molecular characterization of the oxidative branch of glycerol utilization by Citrobacter freundii
Institut fur Mikrobiologie, Georg-August-Universitat Gottingen, Germany.
This article has been cited by other articles:
| Appl. Environ. Microbiol. | Infect. Immun. | Eukaryot. Cell |
|---|---|---|
| Mol. Cell. Biol. | J. Virol. | Microbiol. Mol. Biol. Rev. |
| ALL ASM JOURNALS |