In this paper, I describe the molecular and functional characterizations of three distinct biocatalysts of biotechnological interest for the purpose of showing that they are interesting examples of the functional and structural differentiation of enzymes within protein families. These biocatalysts are the Saccharopolyspora rectivirgula β-galactosidase (srbg) of the glycosyl hydrolase family 2, the Bacillus sp. SAM1606 α-glucosidase of the glycosyl hydrolase family 13, and the Antirrhinum majus aureusidin synthase (AmAS1) of the plant polyphenol oxidase family. These biocatalysts were found to be clearly distinct from other members of each family, mainly in terms of subunit structure and metal ion requirements (for srbg), substrate specificity and transglucosylation activity (for SAM1606 α-glucosidase), and biological function (for AmAS1). Extensive analyses of such unique properties and functions through protein and genetic engineering approaches provided important information for insights into the molecular and functional evolution of each protein family.
|Number of pages||7|
|Publication status||Published - 2002|
- Glycosyl hydrolase family
- Molecular evolution
- Plant polyphenol oxidase