Enhancement of coenzyme binding by a single point mutation at the coenzyme binding domain of E. coli lactaldehyde dehydrogenase.

ABSTRACT: Phenylacetaldehyde dehydrogenase (PAD) and lactaldehyde dehydrogenase (ALD) share some structural and kinetic properties. One difference is that PAD can use NAD+ and NADP+, whereas ALD only uses NAD+. An acidic residue has been involved in the exclusion of NADP+ from the active site in pyridine nucleotide-dependent dehydrogenases. However, other factors may participate in NADP+ exclusion. In the present work, analysis of the sequence of the region involved in coenzyme binding showed that residue F180 of ALD might participate in coenzyme specificity. Interestingly, F180T mutation rendered an enzyme (ALD-F180T) with the ability to use NADP+. This enzyme showed an activity of 0.87 micromol/(min * mg) and K(m) for NADP+ of 78 microM. Furthermore, ALD-F180T exhibited a 16-fold increase in the V

SUBMITTER: Rodriguez-Zavala JS 

PROVIDER: S-EPMC2248313 | biostudies-literature | 2008 Mar

REPOSITORIES: biostudies-literature