DIVERGENT EVOLUTION OF ENZYMATIC FUNCTION: Mechanistically Diverse Superfamilies and Functionally Distinct Suprafamilies

• Published in: Annual review of biochemistry Vol. 70; no. 1; pp. 209 - 246
• Main Authors: Gerlt, John A, Babbitt, Patricia C
• Format: Journal Article
• Language: English
• Published: Palo Alto, CA 94303-0139 Annual Reviews 01-01-2001; 4139 El Camino Way, P.O. Box 10139 Annual Reviews, Inc; USA
• Subjects: (β/α)-barrels; amidohydrolase; Amidohydrolases - chemistry; Amidohydrolases - metabolism; Catalytic Domain; crotonase; enolase; Enoyl-CoA Hydratase - chemistry; Enoyl-CoA Hydratase - metabolism; Enzymes; Enzymes - chemistry; Enzymes - metabolism; Evolution; Evolution, Molecular; Histidine - biosynthesis; Oxidoreductases - chemistry; Oxidoreductases - metabolism; Phosphopyruvate Hydratase - chemistry; Phosphopyruvate Hydratase - metabolism; Phosphoric Diester Hydrolases - chemistry; Phosphoric Diester Hydrolases - metabolism; Proteins; Substrate Specificity; thiyl radical; Tryptophan - biosynthesis
• ISSN: 0066-4154; 1545-4509
• DOI: 10.1146/annurev.biochem.70.1.209

The protein sequence and structure databases are now sufficiently
representative that strategies nature uses to evolve new catalytic functions
can be identified. Groups of divergently related enzymes whose members catalyze
different reactions but share a common partial reaction, intermediate, or
transition state (mechanistically diverse superfamilies) have been discovered,
including the enolase, amidohydrolase, thiyl radical, crotonase,
vicinal-oxygen-chelate, and Fe-dependent oxidase superfamilies. Other groups of
divergently related enzymes whose members catalyze different overall reactions
that do not share a common mechanistic strategy (functionally distinct
supra
families) have also been identified: (
a
) functionally
distinct suprafamilies whose members catalyze successive transformations in the
tryptophan and histidine biosynthetic pathways and (
b
) functionally
distinct suprafamilies whose members catalyze different reactions in different
metabolic pathways. An understanding of the structural bases for the catalytic
diversity observed in super- and suprafamilies may provide the basis for
discovering the functions of proteins and enzymes in new genomes as well as
provide guidance for in vitro evolution/engineering of new enzymes.