Molecular architecture of DesV from Streptomyces venezuelae: a PLP-dependent transaminase involved in the biosynthesis of the unusual sugar desosamine.

ABSTRACT: Desosamine is a 3-(dimethylamino)-3,4,6-trideoxyhexose found in certain macrolide antibiotics such as the commonly prescribed erythromycin. Six enzymes are required for its biosynthesis in Streptomyces venezuelae. The focus of this article is DesV, which catalyzes the PLP-dependent replacement of a 3-keto group with an amino functionality in the fifth step of the pathway. For this study the three-dimensional structures of both the internal aldimine and the ketimine intermediate with glutamate were determined to 2.05 A resolution. DesV is a homodimer with each subunit containing 12 alpha-helical regions and 12 beta-strands that together form three layers of sheet. The structure of the internal aldimine demonstrates that the PLP-cofactor is held in place by residues contributed from both sub

SUBMITTER: Burgie ES 

PROVIDER: S-EPMC2206644 | biostudies-literature | 2007 May

REPOSITORIES: biostudies-literature