2003 Fiscal Year Final Research Report Summary
Analysis of microbial metabolism of biosulfur compounds and adaptive evolution for the degradation of xenobiotics
Project/Area Number |
14360050
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Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
応用微生物学・応用生物化学
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Research Institution | Shibaura Institute of Technology (2003) The University of Tokyo (2002) |
Principal Investigator |
OMORI Toshio Shibaura Institute of Technology, Department of Applied Chemistry, Prof., 大学院・工学研究科, 教授 (20011984)
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Project Period (FY) |
2002 – 2003
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Keywords | Dimethyl Sulfide / Dibenzothiophene / Organic sulfur compounds / Dimethyl Sulfone / sigma54 / Sulfate starvation |
Research Abstract |
Microbial dimethyl sulfide (DMS) conversion is thought to be involved in the global sulfur cycle. We isolated Pseudomonas putida strain DS1 from soil as a bacterium utilizing DMS as a sole sulfur source, and tried to elucidate the DMS conversion mechanism of strain DS1 at biochemical and genetic level. Strain DS1 oxidized DMS to dimethyl sulfone ( DMSO_2) via dimethyl sulfoxide, whereas the oxidation was repressed in the presence of sulfate, suggesting that a sulfate starvation response is involved in DMS utilization by starin DS1. Two of the five DMS-utilization-defective mutants isolated by transposon5 (Th5) mutagenesis had a Tn5 insertion in the ssuEAECBF operon, which has been reported to encode a two-component monooxygenase system (SsuED), an ABC-type transporter (SsuABC), and a small protein (SsuF), and also to play a key role in utilization of sulfonates and sulfate esters in another bacterium, P.pulida strain S-313. Disniption of ssuD and SsuD enzymatic activity demonstrated that methanesulfonate is a metabolic intermediate of DMS and desulfonated by SsuD.Disruption of ssuC cr ssuF also led to a DMS-utilization-defective phenotype. Another two mutants bad a defect in a gene homologous to pa2354 from P.aeruginosa PA01, which encodes a putative transcriptional regulator, while the remaining mutant had a defect in cysM encoding O-acetylserine(thio)-lyase B.
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