Properties and applications of phytepsins from thistle flowers

VAIRO CAVALLI, S.; LUFRANO, D.; COLOMBO, MA.L.; PRIOLO, N.S

PHYTOCHEMISTRY

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2013 vol. 92 p. 16 - 32

0031-9422

Aqueous extracts of thistle flowers from the genus Cynara?Cardueae tribe Cass. (CynareaeLess.), Asteraceae Dumortier?are traditionally used in the Mediterranean region for the production of artisanal cheeses because of the presence of aspartic proteases (APs) with the ability to coagulate milk. Plant APs, collectively known as phytepsins (EC 3.4.23.40), are bilobed endopeptidases present in an ample variety of plant species with activity mainly at acidic pHs and two aspartic residues located on each side of a catalytic cleft that are responsible for catalysis. The cleavage of the scissile peptide-bond occurs primarily between residues with large hydrophobic side chains. Even when aspartylendopeptidase activity in plants is normally present at relatively low levels overall, the flowers of several species of the Cardueae tribe possess extremely active APs in certain tissues. For this reason, in the last two decades, the APs present in thistle flowers have been the subject of intensive study. We present here a compilation of that work that summarizes the known chemical and biologic properties of these proteases as well as their biomedical and biotechnological applications.