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Team:Tokyo-NoKoGen/g3dh
From 2014.igem.org
About G3DH
The glucose-3-dehydrogenase (G3DH) operon from Rhizobium tumefaciens EHA101 encodes the heterotrimer G3DH, which converts glucose to 3-ketoglucose. The deduced primary structure and secondary structure of G3DH are similar to sorbitol dehydrogenase from Gluconobacter oxidans and 2-keto-D-gluconate dehydrogenases from Erwinia herbicola. These enzymes are composed of three subuints; catalytic subunit, cytochrome c subunit, and small subunit. Catalytic domain has flavin adenine dinucleotide (FAD) as a cofactor. And cytochrome c subunit bounds to cytoplasmic membrane. The function of small subunit is unknown.
This G3DH we use also has cytochrome c subunit. Cytochrome c subunit needs to be matured by cytochrome c maturation enzymes (CCM). Therefore, we use the plasmid, pEC86 which has the gene of CCM.
And this G3DH is a homolog of G3DH from a marine bacterium Halomonas sp. α-15 which shows wide substrate specificity. It is already reported that G3DH from Halomonas sp. α-15 can also convert trehalose (a disaccharide made up of two glucose moieties) into 3,3´-diketotrehalose, which is trehalase inhibitor. Therefore, the G3DH we use can also convert trehalose to 3,3´-diketotrehalose.
Reference
(1) Cloning and Expression of Glucose 3-Dehydrogenase from Halomonas sp. α-15 in Escherichia coli.,(2001),K Kojima et al.,
(2) Overproduction of the Bradyrhizobium japonicum c-Type Cytochrome Subunits of the cbb3 Oxidase in Escherichia coli.,(1998),E Arslan et al.,
