Current Genetics

, Volume 18, Issue 1, pp 71–76

The development of a heterologous transformation system for the cellulolytic fungus Trichoderma reesei based on a pyrG-negative mutant strain

  • F. Gruber
  • J. Visser
  • C. P. Kubicek
  • L. H. de Graaff
Original Articles

DOI: 10.1007/BF00321118

Cite this article as:
Gruber, F., Visser, J., Kubicek, C.P. et al. Curr Genet (1990) 18: 71. doi:10.1007/BF00321118

Summary

Six uridine auxotroph mutants of Trichoderma reesei QM 9414 were isolated by resistance to 5-fluoroorotic acid and one strain was identified as OMP-decarboxylase negative (pyr-) by a radiometric enzyme assay. Transformation to uridine prototrophy was achieved with the pyr4 gene of Neurospora crassa (up to 1500 transformants/μg) and with pyrA of Aspergillus niger (700–800 transformants/μg). In many transformants the PYR+ function seems to be present as extrachromosomal DNA. There is evidence for a correlation between the stability of transformants and integration of the vector in the genome whereas unstable transformants are obtained when autonomous replication of the plasmid occurs.

Key words

Trichoderma reeseiTransformationOMP-decarboxylaseVector integrationAutonomous replication

Copyright information

© Springer-Verlag 1990

Authors and Affiliations

  • F. Gruber
    • 1
  • J. Visser
    • 2
  • C. P. Kubicek
    • 1
  • L. H. de Graaff
    • 2
  1. 1.Abt Mikrobielle Biochemie, Institut für Biochemische Technologie und MikrobiologieTU WienWienAustria
  2. 2.Department of GeneticsAgricultural UniversityWageningenThe Netherlands