Histidine residue at position 234 of oxidosqualene-lanosterol cyclase from Saccharomyces cerevisiae simultaneously influences cyclization, rearrangement, and deprotonation reactions

Abstract

Multiple triterpenes, including achilleol A (1), protosta-12,24-dien- 3β-ol (2), lanosterol (3), and parkeol (4; 14:26:51:9) were isolated from an ERG7 oxidosqualene-lanosterol cyclase-deficient Saccharomyces cerevisiae TKW14 strain that expresses the ERG7H234Y mutation. The results indicate a role for H234 in modulating multiple aspects of the oxidosqualene cyclization/rearrangement reaction, including cyclization, rearrangement, and deprotonation. © 2005 Wiley-VCH Verlag GmbH & Co. KGaA.