Molecular and General Genetics MGG

, Volume 252, Issue 4, pp 420–428

Yeast chitin synthases 1 and 2 consist of a non-homologous and dispensable N-terminal region and of a homologous moiety essential for function

  • R. A. Ford
  • J. A. Shaw
  • E. Cabib
Original Paper

DOI: 10.1007/BF02173007

Cite this article as:
Ford, R.A., Shaw, J.A. & Cabib, E. Molec. Gen. Genet. (1996) 252: 420. doi:10.1007/BF02173007

Abstract

Predicted protein sequences of fungal chitin synthases can be divided into a non-homologous N-terminal region and a C-terminal region that shows significant homology among the various synthases. We have explored the function of these domains by constructing a series of nested deletions, extending from either end, in theCHS1 andCHS2 genes ofSaccharomyces cerevisiae. In both cases, most or all of the sequences encoding the non-homologous N-terminal region (one-third of the protein for Chs1p and about one-fourth for Chs2p) could be excised, with little effect on the enzymatic activity in vitro of the corresponding synthase or on its function in vivo. However, further small deletions (20–25 amino acids) into the homologous region were deleterious to enzymatic activity and function, and often led to changes in the zymogenic character of the enzymes. Similarly, relatively small (about 75 amino acids) deletions from the C-terminus resulted in loss of enzymatic activity and function of both synthases. Thus, it appears that all the information necessary for membrane localization, enzymatic activity and function resides in the homologous regions of Chs1p and Chs2p, a situation that may also apply to other chitin synthases.

Key words

Saccharomyces cerevisiaeChitin synthasesSeptum

Copyright information

© Springer-Verlag 1996

Authors and Affiliations

  • R. A. Ford
    • 1
  • J. A. Shaw
    • 1
  • E. Cabib
    • 1
  1. 1.National Institute of Diabetes, Digestive and Kidney Diseases, Laboratory of Biochemistry and MetabolismNational Institutes of HealthBethesdaUSA
  2. 2.Bio-Rad Laboratories, Inc.HerculesUSA