Non-homologous isofunctional enzymes: a systematic analysis of alternative solutions in enzyme evolution.

ABSTRACT:

Background

Evolutionarily unrelated proteins that catalyze the same biochemical reactions are often referred to as analogous - as opposed to homologous - enzymes. The existence of numerous alternative, non-homologous enzyme isoforms presents an interesting evolutionary problem; it also complicates genome-based reconstruction of the metabolic pathways in a variety of organisms. In 1998, a systematic search for analogous enzymes resulted in the identification of 105 Enzyme Commission (EC) numbers that included two or more proteins without detectable sequence similarity to each other, including 34 EC nodes where proteins were known (or predicted) to have distinct structural folds, indicating independent evolutionary origins. In the past 12 years, many putative non-homologous isofuncti

SUBMITTER: Omelchenko MV 

PROVIDER: S-EPMC2876114 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature