The stereospecificity of hydrogen transfer to NAD(P)+ catalyzed by lactol dehydrogenases.
The stereochemistry of hydrogen transfer to NAD(P)+ has been determined for five lactol dehydrogenases. It was found that D-glucose dehydrogenases from Bacillus megaterium and Cryptococcus uniguttulatus and L-rhamnose dehydrogenase from Aureobasidium pullulans are pro-S (B) specific, while D-glucose dehydrogenase from Thermoplasma acidophilum and D-xylose dehydrogenase from procine liver are pro-R (A) specific. The latter two enzymes are the first examples of A-specific dehydrogenases oxidizing aldoses at the anomeric carbon. These findings are discussed in terms of functional and historical models that seek to make predictive generalizations regarding dehydrogenase stereospecificity.
Mostad
S B
SB
Department of Chemistry, Reed College, Portland, Oregon 97202, USA.
Helming
H L
HL
Groom
C
C
Glasfeld
A
A
D000818:Animals; D001410:Bacillus megaterium / Q000201:enzymology; D002237:Carbohydrate Dehydrogenases / Q000378:metabolism*; D003454:Cryptococcus / Q000201:enzymology; D006859:Hydrogen / Q000378:metabolism*; D008099:Liver / Q000201:enzymology; D009682:Magnetic Resonance Spectroscopy; D003904:Mitosporic Fungi / Q000201:enzymology; D009243:NAD / Q000737:chemistry / Q000378:metabolism*; D009249:NADP / Q000737:chemistry / Q000378:metabolism*; D013237:Stereoisomerism; D013379:Substrate Specificity; D013552:Swine; D013822:Thermoplasma / Q000201:enzymology
D009243:NAD; D009249:NADP; D006859:Hydrogen; D002237:Carbohydrate Dehydrogenases