Overexpression of the gene encoding GTP: mannose-1-phosphate guanyltransferase, mpg1, increases cellular GDP-mannose levels and protein mannosylation in Trichoderma reesei

Anna Zakrzewska, Grazyna Palamarczyk, Hubert Krotkiewski, Ewa Zdebska, Markku Saloheimo, Merja Penttilä, Joanna S. Kruszewska

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

To elucidate the regulation and limiting factors in the glycosylation of secreted proteins, the mpg1 and dpm1 genes from Trichoderma reesei (Hypocrea jecorina) encoding GTP:α-D-mannose-1-phosphate guanyltransferase and dolichyl phosphate mannose synthase (DPMS), respectively, were overexpressed in T. reesei. No significant increases were observed in DPMS activity or protein secretion in dpm1-overexpressing transformants, whereas overexpression of mpg1 led to a twofold increase in GDP-mannose (GDPMan) levels. GDPMan was effectively utilized by mannnosyltransferases and resulted in hypermannosylation of secreted proteins in both N and O glycosylation. Overexpression of the mpg1 gene also increased the transcription of the dpm1 gene and DPMS activity. Our data indicate that the level of cellular GDPMan can play a major regulatory role in protein glycosylation in T. reesei.

Original languageEnglish
Pages (from-to)4383-4389
Number of pages7
JournalApplied and Environmental Microbiology
Volume69
Issue number8
DOIs
Publication statusPublished - 1 Aug 2003
MoE publication typeA1 Journal article-refereed

    Fingerprint

Cite this