Selective cloning of genes encoding RNase H from Salmonella typhimurium, Saccharomyces cerevisiae and Escherichia coli rnh mutant

Mol Gen Genet. 1991 Jul;227(3):438-45. doi: 10.1007/BF00273935.


We have cloned genes encoding RNase H from Escherichia coli rnh mutants, Salmonella typhimurium and Saccharomyces cerevisiae. Selection was accomplished by suppression of the temperature-sensitive growth phenotype of Escherichia coli strains containing the rnh-339::cat and either recB270 (Ts) or recC271 (Ts) mutations. RNases H from E. coli and S. typhimurium contained 155 amino acid residues and differed at only 11 positions. The S. cerevisiae and E. coli RNases H were about 30% homologous. A comparison of the amino acid sequences of several RNases H from cellular and retroviral sources revealed some strongly conserved regions as well as variable regions; the carboxyl-terminus was particularly variable. The overlapping, divergent promoter gene organization found in E. coli was observed to be present in S. typhimurium.

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Cloning, Molecular
  • Endoribonucleases / genetics*
  • Escherichia coli / genetics*
  • Genes, Bacterial
  • Genes, Fungal
  • Molecular Sequence Data
  • Mutation*
  • Nucleic Acid Hybridization
  • Phenotype
  • Plasmids
  • Promoter Regions, Genetic
  • Ribonuclease H
  • Saccharomyces cerevisiae / genetics*
  • Salmonella typhimurium / genetics*
  • Sequence Homology, Nucleic Acid


  • Endoribonucleases
  • Ribonuclease H

Associated data

  • GENBANK/S47099
  • GENBANK/S47111
  • GENBANK/S47117
  • GENBANK/X63981
  • GENBANK/X63982
  • GENBANK/X63983
  • GENBANK/X63984
  • GENBANK/X63985
  • GENBANK/X63986
  • GENBANK/X63987