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PubMed · 7607475

Restriction-modification systems in Lactococcus lactis.

N Nyengaard·F K Vogensen·J Josephsen
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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.

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Base SequenceCloning, MolecularDNA Restriction EnzymesDeoxyribonucleases, Type II Site-SpecificGenes, BacterialKineticsLactococcus lactisPlasmidsRecombinant ProteinsSubstrate SpecificityComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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N Nyengaard, F K Vogensen, J Josephsen. 1995-05-19. Restriction-modification systems in Lactococcus lactis.. https://doi.org/10.1016/0378-1119(95)91235-r

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