The ASP1 gene of Saccharomyces cerevisiae, encoding the intracellular isozyme of L-asparaginase

Gene. 1994 Jun 24;144(1):37-43. doi: 10.1016/0378-1119(94)90200-3.

Abstract

Saccharomyces cerevisiae produces two L-asparaginases (ASPs), intracellular ASP I and cell-wall ASP II. In this report, the ASP-I-encoding gene, ASP1, has been identified by homology cloning based on the structures of ASPs from other organisms. Its deduced protein product has a subunit M(r) of 41,414, and shows substantial sequence homology to the bacterial amidohydrolase family. The product of the S. cerevisiae ASP3 gene, a further member of this family, encoding the nitrogen catabolite-regulated cell-wall ASP II, has 46% overall sequence identity to ASP1. Duplication of ancestral asparaginase genes, resulting in separate intra- and extracellular isozymes, appears to have occurred independently in the prokaryotic and eukaryotic lineages. Exact physical mapping of the new cloned ASP1 gene locates it 73% of the distance from the left telomere of chromosome IV, at a position precisely matching the known genetic map location of ASP1. This, along with the structural features of the clone, confirms that ASP1 is the structural gene encoding cytoplasmic ASP I in S. cerevisiae. Sequence analysis of the ethylmethanesulfonate-induced asp1-12 allele of strain XE101-1A revealed a C-->T transition altering Ala176 to Val. This residue lies within a highly conserved region, and the results suggests a critical function for Ala176 in ASP function. Expression of ASP1 and other recombinant ASPs may allow access to improved products for use in the chemotherapy of leukaemia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Asparaginase / genetics*
  • Base Sequence
  • Biological Evolution
  • Chromosome Mapping
  • Chromosomes, Fungal
  • Cloning, Molecular
  • DNA, Recombinant
  • Isoenzymes / genetics*
  • Molecular Sequence Data
  • Mutation
  • Saccharomyces cerevisiae / enzymology
  • Saccharomyces cerevisiae / genetics*
  • Sequence Homology, Amino Acid
  • Transcription, Genetic

Substances

  • DNA, Recombinant
  • Isoenzymes
  • Asparaginase

Associated data

  • GENBANK/Z27406