Molecular and General Genetics MGG

, Volume 251, Issue 5, pp 542–550

Regulation of acid phosphatases in anAspergillus niger pacC disruption strain

  • J. P. T. W. van den Hombergh
  • A. P. MacCabe
  • P. J. I. van de Vondervoort
  • J. Visser
Original Paper

DOI: 10.1007/BF02173643

Cite this article as:
van den Hombergh, J.P.T.W., MacCabe, A.P., van de Vondervoort, P.J.I. et al. Molec. Gen. Genet. (1996) 251: 542. doi:10.1007/BF02173643

Abstract

AnAspergillus niger strain has been constructed in which the pH-dependent regulatory gene,pacC, was disrupted. ThepacC gene ofA. niger, like that ofA. nidulans, is involved in the regulation of acid phosphatase expression. Disruptants were identified by a reduction in acid phosphatase staining of colonies. Southern analysis demonstrated integration of the disruption plasmid at thepacC locus and Northern analysis showed that the disruption strain produced a truncatedpacC mRNA of 2.2 kb (as compared to 2.8 kb in the wild type). The strain carrying thepacC disruption was used to assign thepacC gene to linkage group IV; this was confirmed by CHEF electrophoresis and Southern analysis. This strain further allowed us to determine which extracellular enzyme and transport systems are under the control ofpacC inA. niger. Expression of theA. niger pacC wild-type gene and the truncatedpacC gene showed that, in contrast to the auto-regulated wild-type expression, which was elevated only at alkaline pH, the truncatedpacC gene was deregulated, as high-level expression occurred regardless of the pH of the culture medium. Analysis of the phosphatase spectrum by isoelectric focussing and enzyme activity staining both in the wild-type and thepacC disruptant showed that at least three acid phosphatases are regulated by thepacC. For the single alkaline phosphatase no pH regulation was observed.

Key words

Phosphate repressionGene disruptionEnzyme localization

Copyright information

© Springer-Verlag 1996

Authors and Affiliations

  • J. P. T. W. van den Hombergh
    • 1
  • A. P. MacCabe
    • 1
  • P. J. I. van de Vondervoort
    • 1
  • J. Visser
    • 1
  1. 1.Section Molecular Genetics of Industrial MicroorganismsWageningen Agricultural UniversityWageningenThe Netherlands
  2. 2.CSIC/IATA, Instituto de Agroquimica y Tecnologia de Alimentos, Poligono de La Coma S/NPaterna ValenciaSpain