Structure and regulation of the gene for dGTP triphosphohydrolase from Escherichia coli

Proc Natl Acad Sci U S A. 1990 Apr;87(7):2740-4. doi: 10.1073/pnas.87.7.2740.

Abstract

Escherichia coli encodes an enzyme, deoxyguanosine triphosphate triphosphohydrolase (dGTPase, EC 3.1.5.1), that cleaves dGTP into deoxyguanosine and tripolyphosphate. An E. coli mutant, optA1, contains a 50-fold increased level of dGTPase and cannot support the growth of phage T7 defective in [corrected] gene 1.2, whose product is an inhibitor of dGTPase. The optA1 mutation maps to 3.6 min on the E. coli chromosome and is closely linked to dapD. We have isolated the gene encoding dGTPase (dgt) from wild-type E. coli and determined its nucleotide sequence. The dgt gene lies immediately upstream of htrA and 6 kilobases from dapD, in the same region as the optA1 mutation. The dgt structural gene is 1515 base pairs, encoding a protein of 59,315 daltons, in agreement with the size and N-terminal amino acid sequence of the purified protein. An E. coli strain containing a null allele has no detectable phenotype when grown at 30-42 degrees C in rich medium. A transition of C to T in a potential promoter of dgt is required for expression of the optA1 phenotype.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Bacteriophage lambda / genetics
  • Base Sequence
  • Escherichia coli / enzymology
  • Escherichia coli / genetics*
  • Gene Expression Regulation, Bacterial*
  • Gene Expression Regulation, Enzymologic
  • Genes, Bacterial*
  • Molecular Sequence Data
  • Oligonucleotide Probes
  • Phosphoric Monoester Hydrolases / genetics*
  • Phosphoric Monoester Hydrolases / metabolism
  • Plasmids
  • Restriction Mapping

Substances

  • Oligonucleotide Probes
  • Phosphoric Monoester Hydrolases

Associated data

  • GENBANK/M31772