PDBsum entry 5a04

Oxidoreductase

PDB id: 5a04

Contents

Protein chains

(+ 0 more) 335 a.a.

Ligands

NDP ×6

BGC ×9

DIO ×5

SO4 ×6

Waters ×2037

PDB id:

5a04

Name:

Oxidoreductase

Title:

Crystal structure of aldose-aldose oxidoreductase from caulobacter crescentus complexed with glucose

Structure:

Aldose-aldose oxidoreductase. Chain: a, b, c, d, e, f. Engineered: yes

Source:

Caulobacter crescentus cb15. Organism_taxid: 190650. Strain: cb15. Expressed in: saccharomyces cerevisiae. Expression_system_taxid: 4932

Resolution:

1.70Å R-factor: 0.160 R-free: 0.181

Authors:

H.Taberman,J.Rouvinen,T.Parkkinen

Key ref:

H.Taberman et al. (2015). Structure and function of Caulobacter crescentus aldose-aldose oxidoreductase. Biochem J, 472, 297-307. PubMed id: 26438878 DOI: 10.1042/BJ20150681

Date:

17-Apr-15 Release date: 21-Oct-15

Protein chains

Q9A8X3  (Q9A8X3_CAUVC) -  Glucose-fructose oxidoreductase from Caulobacter vibrioides (strain ATCC 19089 / CB15)

Seq: 366 a.a.

Struc: 335 a.a.

Enzyme reactions

• Enzyme class: E.C.1.1.99.- - ?????

DOI no: 10.1042/BJ20150681

Biochem J 472:297-307 (2015)

PubMed id: 26438878

Structure and function of Caulobacter crescentus aldose-aldose oxidoreductase.

H.Taberman, M.Andberg, A.Koivula, N.Hakulinen, M.Penttilä, J.Rouvinen, T.Parkkinen.

ABSTRACT

Aldose-aldose oxidoreductase (Cc AAOR) is a recently characterized enzyme from the bacterial strain Caulobacter crescentus CB15 belonging to the glucose-fructose oxidoreductase/inositol dehydrogenase/rhizopine catabolism protein (Gfo/Idh/MocA) family. Cc AAOR catalyses the oxidation and reduction of a panel of aldose monosaccharides using a tightly bound NADP(H) cofactor that is regenerated in the catalytic cycle. Furthermore, Cc AAOR can also oxidize 1,4-linked oligosaccharides. In the present study, we present novel crystal structures of the dimeric Cc AAOR in complex with the cofactor and glycerol, D-xylose, D-glucose, maltotriose and D-sorbitol determined to resolutions of 2.0, 1.8, 1.7, 1.9 and 1.8 Å (1 Å=0.1 nm), respectively. These complex structures allowed for a detailed analysis of the ligand-binding interactions. The structures showed that the C1 carbon of a substrate, which is either reduced or oxidized, is close to the reactive C4 carbon of the nicotinamide ring of NADP(H). In addition, the O1 hydroxy group of the substrate, which is either protonated or deprotonated, is unexpectedly close to both Lys(104) and Tyr(189), which may both act as a proton donor or acceptor. This led us to hypothesize that this intriguing feature could be beneficial for Cc AAOR to catalyse the reduction of a linear form of a monosaccharide substrate and the oxidation of a pyranose form of the same substrate in a reaction cycle, during which the bound cofactor is regenerated.