Abstract
We measured the activity and stability of three mannosyltransferases to ascertain the mechanisms of changes in the antigenicity and the mannan structure of Candida albicans cells cultured at high temperature (37 °C) under acidic (pH 2.0) conditions in a liquid medium. The α-1,6-mannosyltransferase (α-1,6-MT) activity of the particulate-insoluble enzyme fractions prepared from C. albicans J-1012 (J-1012) cells cultured at 37 °C was retained compared to those at 27 °C, whereas β-1,2-mannosyltransferase II (β-1,2-MT II) activity was detected in the 27 °C fraction but not in the 37 °C fraction. Similar results were obtained in the fraction prepared from J-1012 cells cultured at pH 2.0. The α-1,6-MT activities of fractions prepared from C. albicans NIH B-792 (B-792) strain cells cultured at 37 °C were retained compared to those at 27 °C, whereas β-1,2-mannosyltransferase VI-6 (β-1,2-MT VI-6) activity was detected in the fraction of B-792 cells cultured at 27 °C but not detected in the 37 °C fraction. We also found that the β-1,2-MT II and β-1,2-MT VI-6 activity of C. albicans cells was more sensitive to both high temperature and low pH compared with α-1,6-MT activity.
