title: Chitin synthetase activity is bound to the plasma membrane and to a cytoplasmic particulate fraction in Candida albicans germ tube cells.
abstract: Subcellular distribution of chitin synthetase has been studied in germ tubes of Candida albicans. Two fractions with synthetase activity were separated from cell homogenates: (i) a mixed membrane fraction where the enzyme, partly in an active form, is associated with the plasma membrane (isopycnic centrifugation of mixed membrane fraction on linear sucrose gradients resolved a unique peak of activity matching with [3H]ConA-labelled membranes at a buoyant density of 1.195 g/ml); and (ii) a cytoplasmic fraction containing fully zymogenic enzyme associated with particles whose buoyant density (determined by isopycnic centrifugation on linear sucrose gradients) depended on the cell breakage conditions. The actual cytoplasmic fraction-enzyme may correspond to particles with buoyant density 1.135 g/ml (chitosomes), whereas the enzyme particles with other densities (1.085 and 1.165 g/ml) probably originated during cell disruption, as has been reported previously to occur during the preparation of yeast cell homogenates.
authors.affiliation: Unitat de Microbiología, Facultat de Farmàcia, Universitat de València, Spain.
authors.forename: D
authors.initials: D
authors.lastname: Gozalbo
authors.forename: F
authors.initials: F
authors.lastname: Dubón
authors.forename: R
authors.initials: R
authors.lastname: Sentandreu
mesh_terms: D002176:Candida albicans / Q000201:enzymology* / Q000648:ultrastructure; D002462:Cell Membrane / Q000201:enzymology; D002687:Chitin Synthase / Q000378:metabolism*; D003593:Cytoplasm / Q000201:enzymology*
chemical_list: D002687:Chitin Synthase