3-Keto-5-aminohexanoate cleavage enzyme: a common fold for an uncommon Claisen-type condensation.

ABSTRACT: The exponential increase in genome sequencing output has led to the accumulation of thousands of predicted genes lacking a proper functional annotation. Among this mass of hypothetical proteins, enzymes catalyzing new reactions or using novel ways to catalyze already known reactions might still wait to be identified. Here, we provide a structural and biochemical characterization of the 3-keto-5-aminohexanoate cleavage enzyme (Kce), an enzymatic activity long known as being involved in the anaerobic fermentation of lysine but whose catalytic mechanism has remained elusive so far. Although the enzyme shows the ubiquitous triose phosphate isomerase (TIM) barrel fold and a Zn(2+) cation reminiscent of metal-dependent class II aldolases, our results based on a combination of x-ray snapshots and

SUBMITTER: Bellinzoni M 

PROVIDER: S-EPMC3149333 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature