title: CO-dependent H2 production by genetically engineered Thermococcus onnurineus NA1.
abstract: Hydrogenogenic CO oxidation (CO + H(2)O → CO(2) + H(2)) has the potential for H(2) production as a clean renewable fuel. Thermococcus onnurineus NA1, which grows on CO and produces H(2), has a unique gene cluster encoding the carbon monoxide dehydrogenase (CODH) and the hydrogenase. The gene cluster was identified as essential for carboxydotrophic hydrogenogenic metabolism by gene disruption and transcriptional analysis. To develop a strain producing high levels of H(2), the gene cluster was placed under the control of a strong promoter. The resulting mutant, MC01, showed 30-fold-higher transcription of the mRNA encoding CODH, hydrogenase, and Na(+)/H(+) antiporter and a 1.8-fold-higher specific activity for CO-dependent H(2) production than did the wild-type strain. The H(2) production potential of the MC01 mutant in a bioreactor culture was 3.8-fold higher than that of the wild-type strain. The H(2) production rate of the engineered strain was severalfold higher than those of any other CO-dependent H(2)-producing prokaryotes studied to date. The engineered strain also possessed high activity for the bioconversion of industrial waste gases created as a by-product during steel production. This work represents the first demonstration of H(2) production from steel mill waste gas using a carboxydotrophic hydrogenogenic microbe.
authors: Korea Institute of Ocean Science and Technology, Ansan, South Korea.
authors: Min-Sik
authors: MS
authors: Kim
authors: Seung Seob
authors: SS
authors: Bae
authors: Yun Jae
authors: YJ
authors: Kim
authors: Tae Wan
authors: TW
authors: Kim
authors: Jae Kyu
authors: JK
authors: Lim
authors: Seong Hyuk
authors: SH
authors: Lee
authors: Ae Ran
authors: AR
authors: Choi
authors: Jeong Ho
authors: JH
authors: Jeon
authors: Jung-Hyun
authors: JH
authors: Lee
authors: Hyun Sook
authors: HS
authors: Lee
authors: Sung Gyun
authors: SG
authors: Kang
mesh_terms: D019149:Bioreactors; D002248:Carbon Monoxide / Q000378:metabolism*; D015870:Gene Expression; D020869:Gene Expression Profiling; D055786:Gene Knockout Techniques; D006859:Hydrogen / Q000378:metabolism*; D007218:Industrial Microbiology / Q000379:methods; D060847:Metabolic Engineering; D053858:Metabolic Networks and Pathways / Q000235:genetics*; D005810:Multigene Family; D010084:Oxidation-Reduction; D011401:Promoter Regions, Genetic; D019712:Thermococcus / Q000235:genetics* / Q000378:metabolism*
chemical_list: D002248:Carbon Monoxide; D006859:Hydrogen