Applied Microbiology and Biotechnology

, Volume 48, Issue 5, pp 606–614

Expression of the cefG gene is limiting for cephalosporin biosynthesis in Acremonium chrysogenum

  • S. Gutiérrez
  • J. Velasco
  • A. T. Marcos
  • F. J. Fernández
  • F. Fierro
  • J. L. Barredo
  • B. Díez
  • J. F. Martín
ORIGINAL PAPER

DOI: 10.1007/s002530051103

Cite this article as:
Gutiérrez, S., Velasco, J., Marcos, A. et al. Appl Microbiol Biotechnol (1997) 48: 606. doi:10.1007/s002530051103

Abstract

The conversion of deacetylcephalosporin C to cephalosporin C is inefficient in most Acremonium chrysogenum strains. The cefG gene, which encodes deacetylcephalosporin C acetyltransferase, is expressed very poorly in A. chrysogenum as compared to other genes of the cephalosporin pathway. Introduction of additional copies of the cefG gene with its native promoter (in two different constructions with upstream regions of 1056 bp and 538 bp respectively) did not produce a significant increase of the steady-state level of the cefG transcript. Expression of the cefG gene from the promoters of (i) the glyceraldehyde-3-phosphate dehydrogenase (gpd ) gene of Aspergillus nidulans, (ii) the glucoamylase (gla) gene of Aspergillus niger, (iii) the glutamate dehydrogenase (gdh) and (iv) the isopenicillin N synthase ( pcbC ) genes of Penicillium chrysogenum, led to very high steady-state levels of cefG transcript and to increased deacetylcephalosporin-C acetyltransferase protein concentration (as shown by immunoblotting) and enzyme activity in the transformants. Southern analysis showed that integration of the new constructions occurred at sites different from that of the endogenous cefG gene. Cephalosporin production was increased two- to threefold in A. chrysogenum C10 transformed with constructions in which the cefG gene was expressed from the gdh or gpd promoters as a result of a more efficient acetylation of deacetylcephalosporin C.

Copyright information

© Springer-Verlag Berlin Heidelberg 1997

Authors and Affiliations

  • S. Gutiérrez
    • 1
  • J. Velasco
    • 1
  • A. T. Marcos
    • 1
  • F. J. Fernández
    • 1
  • F. Fierro
    • 1
  • J. L. Barredo
    • 2
  • B. Díez
    • 2
  • J. F. Martín
    • 1
  1. 1.Area of Microbiology, Department of Ecology Genetics and Microbiology, Faculty of Biology, University of León, 24071 León, and Institute of Biotechnology, INBIOTEC, Avda. del Real 1, E-24006 León, Spain Tel.: +34 87 291505 Fax: +34 87 291506 e-mail: degjmm@unileon.esES
  2. 2.Laboratorio de Ingeniería Genética, Antibióticos S.A., 24080 León, SpainES