Restriction-modification systems in Lactococcus lactis

Gene. 1995 May 19;157(1-2):13-8. doi: 10.1016/0378-1119(95)91235-r.

Abstract

Several restriction-modification (R-M) systems have been identified in Lactococcus lactis. Most of the systems have been plasmid encoded and function as phage-resistance mechanisms. At least five different type-II R-M systems, LlaAI, LlaBI, LlaCI, LlaDI and LlaEI, were identified in isolates from a mixed Cheddar starter culture. LlaAI and LlaBI recognized the DNA sequences 5'- decreases GATC-3' and 5'-C decreases TRYAG-3', respectively. The genes coding for the LlaAI and LlaBI R-M systems have been cloned and sequenced. The LlaAI R-M system had two genes coding for methyltransferases (MTases) and one gene coding for a restriction endonuclease (ENase). The MTases showed high homology to the MTases from DpnII. The LlaBI R-M system had one gene coding for a MTase and one gene coding for an ENase.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Cloning, Molecular
  • DNA Restriction Enzymes / genetics
  • DNA Restriction Enzymes / isolation & purification
  • DNA Restriction Enzymes / metabolism*
  • Deoxyribonucleases, Type II Site-Specific / genetics
  • Deoxyribonucleases, Type II Site-Specific / isolation & purification
  • Deoxyribonucleases, Type II Site-Specific / metabolism
  • Genes, Bacterial
  • Kinetics
  • Lactococcus lactis / enzymology*
  • Lactococcus lactis / genetics
  • Plasmids
  • Recombinant Proteins / isolation & purification
  • Recombinant Proteins / metabolism
  • Substrate Specificity

Substances

  • Recombinant Proteins
  • DNA Restriction Enzymes
  • endodeoxyribonuclease SfcI
  • Deoxyribonucleases, Type II Site-Specific
  • GATC-specific type II deoxyribonucleases