RRC ID 30185
Author Yoshida K, Yamaguchi M, Morinaga T, Kinehara M, Ikeuchi M, Ashida H, Fujita Y.
Title myo-Inositol catabolism in Bacillus subtilis.
Journal J Biol Chem
Abstract The iolABCDEFGHIJ operon of Bacillus subtilis is responsible for myo-inositol catabolism involving multiple and stepwise reactions. Previous studies demonstrated that IolG and IolE are the enzymes for the first and second reactions, namely dehydrogenation of myo-inositol to give 2-keto-myo-inositol and the subsequent dehydration to 3D-(3,5/4)-trihydroxycyclohexane-1,2-dione. In the present studies the third reaction was shown to be the hydrolysis of 3D-(3,5/4)-trihydroxycyclohexane-1,2-dione catalyzed by IolD to yield 5-deoxy-d-glucuronic acid. The fourth reaction was the isomerization of 5-deoxy-D-glucuronic acid by IolB to produce 2-deoxy-5-keto-D-gluconic acid. Next, in the fifth reaction 2-deoxy-5-keto-D-gluconic acid was phosphorylated by IolC kinase to yield 2-deoxy-5-keto-D-gluconic acid 6-phosphate. IolR is known as the repressor controlling transcription of the iol operon. In this reaction 2-deoxy-5-keto-D-gluconic acid 6-phosphate appeared to be the intermediate acting as inducer by antagonizing DNA binding of IolR. Finally, IolJ turned out to be the specific aldolase for the sixth reaction, the cleavage of 2-deoxy-5-keto-D-gluconic acid 6-phosphate into dihydroxyacetone phosphate and malonic semialdehyde. The former is a known glycolytic intermediate, and the latter was previously shown to be converted to acetyl-CoA and CO(2) by a reaction catalyzed by IolA. The net result of the inositol catabolic pathway in B. subtilis is, thus, the conversion of myo-inositol to an equimolar mixture of dihydroxyacetone phosphate, acetyl-CoA, and CO(2).
Volume 283(16)
Pages 10415-24
Published 2008-4-18
DOI 10.1074/jbc.M708043200
PII M708043200
PMID 18310071
MeSH Aldehyde-Lyases / metabolism Bacillus subtilis / metabolism* Bacterial Proteins / metabolism Carbon-Carbon Lyases / physiology Catalysis DNA / metabolism DNA-Binding Proteins / metabolism Dihydroxyacetone Phosphate / metabolism Fructose-Bisphosphate Aldolase / physiology Gene Expression Regulation, Bacterial* Gluconates / metabolism Glucuronic Acid / metabolism Hydrolases / physiology Hydrolysis Inositol / metabolism* Models, Biological Models, Chemical Phosphotransferases / physiology Protein Binding Repressor Proteins / metabolism
IF 4.106
Times Cited 70
Prokaryotes E. coli ME9655 ME9656 ME9664
Prokaryotes B. subtilis MBS169 MBS170 MBS171