title: A chitinase gene, chiB, involved in the autolytic process of Aspergillus nidulans.
abstract: Chitinases are thought to be involved in the morphogenesis and autolysis of filamentous fungi. We cloned a gene (chiB) encoding a class V chitinase from Aspergillus nidulans. ChiB expressed in Escherichia coli had chitin-hydrolyzing activity, indicating that chiB encoded a chitinase. Deletion of chiB affected neither germination efficiency nor hyphal growth rate, but considerably reduced the intracellular and extracellular chitinase activities. The decrease in hyphal dry weight during autolytic phase was slower in the mutant than in the wild-type strain. Western blot analysis indicated that the quantity of ChiB significantly increased when the wild-type mycelia were starved for carbon sources, a condition that induced hyphal autolysis. These results suggest that chiB plays an important role in the autolytic process in A. nidulans.
authors.affiliation: Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
authors.forename: Harutake
authors.initials: H
authors.lastname: Yamazaki
authors.forename: Daisuke
authors.initials: D
authors.lastname: Yamazaki
authors.forename: Naoki
authors.initials: N
authors.lastname: Takaya
authors.forename: Masamichi
authors.initials: M
authors.lastname: Takagi
authors.forename: Akinori
authors.initials: A
authors.lastname: Ohta
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Horiuchi
mesh_terms: D000595:Amino Acid Sequence; D001233:Aspergillus nidulans / Q000201:enzymology* / Q000235:genetics*; D001483:Base Sequence; D002686:Chitin / Q000378:metabolism; D002688:Chitinases / Q000235:genetics* / Q000378:metabolism* / Q000502:physiology; D008969:Molecular Sequence Data
chemical_list: D002686:Chitin; D002688:Chitinases