title: The carbohydrate moiety of the acid carboxypeptidase from Aspergillus saitoi.
abstract: Acid carboxypeptidase from Aspergillus saitoi is a glycoprotein that contains both N- and O-linked sugar chains. The N-glycanase released high-mannose type oligosaccharides that were separated into eight components on HPLC. One, which had a unique structure of Man11GlcNAc2, was characterized. Mild alkali treatment of the carboxypeptidase, under conditions that effect beta-elimination, yielded D-mannose. Deglycosylation of the carboxypeptidase with endo-beta-N-acetylglucosaminidase and alpha-mannosidase effected the reduction of the molecular mass from 72 kDa to 60 kDa. Partial changes of CD spectra of the native and the deglycosylated enzymes indicate that some conformational changes on the peptide of the enzyme occurred after deglycosylation. Other enzymatic properties, such as catalytic activity, pH, and thermal stability and resistivity to protease digestion, did not appear to change. Tunicamycin halted secretion of the carboxypeptidase extracellularly.
authors.affiliation: Department of Applied Biological Chemistry, Faculty of Agriculture, Tohoku University, Sendai, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Chiba
authors.forename: Y
authors.initials: Y
authors.lastname: Yamagata
authors.forename: S
authors.initials: S
authors.lastname: Iijima
authors.forename: T
authors.initials: T
authors.lastname: Nakajima
authors.forename: E
authors.initials: E
authors.lastname: Ichishima
mesh_terms: D001230:Aspergillus / Q000201:enzymology*; D002240:Carbohydrate Sequence; D002241:Carbohydrates / Q000737:chemistry; D002268:Carboxypeptidases / Q000737:chemistry* / Q000187:drug effects / Q000302:isolation & purification / Q000378:metabolism; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry; D014415:Tunicamycin / Q000494:pharmacology
chemical_list: D002241:Carbohydrates; D009844:Oligosaccharides; D014415:Tunicamycin; D002268:Carboxypeptidases