title: Disruption of Trichoderma reesei gene encoding protein O-mannosyltransferase I results in a decrease of the enzyme activity and alteration of cell wall composition.
abstract: In fungi transfer of the first mannosyl residue to proteins during their O-glycosylation is catalyzed by protein O-mannosyltransferases encoded by pmt genes. Disruption of the pmt1 gene in Trichoderma caused a significant decrease in the total activity of protein O-mannosyltransferases. Moreover, disruption of the pmt1 gene also led to osmotic sensitivity of the strain, indicating an essential role of the PMTI protein activity for cell wall synthesis. At the same time, the strain was defective in septa formation, producing only half the number of septa per unit length of hypha compared with the wild type. Disruption of the pmt1 gene decreased protein secretion but had no effect on glycosylation of secreted proteins, which suggests that PMTI protein O-mannosyltranferase does not take part in glycosylation of these proteins.
authors.affiliation: Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warszawa, Poland.
authors.forename: Wioletta
authors.initials: W
authors.lastname: Górka-Nieć
authors.forename: Michał
authors.initials: M
authors.lastname: Pniewski
authors.forename: Anna
authors.initials: A
authors.lastname: Kania
authors.forename: Urszula
authors.initials: U
authors.lastname: Perlińska-Lenart
authors.forename: Grazyna
authors.initials: G
authors.lastname: Palamarczyk
authors.forename: Joanna S
authors.initials: JS
authors.lastname: Kruszewska
mesh_terms: D001483:Base Sequence; D002473:Cell Wall / Q000737:chemistry; D004271:DNA, Fungal / Q000235:genetics; D005656:Fungal Proteins / Q000378:metabolism; D005800:Genes, Fungal; D006031:Glycosylation; D008364:Mannosyltransferases / Q000235:genetics* / Q000378:metabolism*; D009154:Mutation; D017384:Sequence Deletion; D014242:Trichoderma / Q000201:enzymology* / Q000235:genetics* / Q000254:growth & development
chemical_list: D004271:DNA, Fungal; D005656:Fungal Proteins; D008364:Mannosyltransferases; C082696:protein O-mannosyltransferase