LLAAI AND LLABI, 2 TYPE-II RESTRICTION ENDONUCLEASES FROM LACTACOCCUS-LACTIS SUBSP CREMORIS W9 AND W56 RECOGNIZING, RESPECTIVELY, 5'- GATC-3' AND 5'-C/TRYAG-3'/

Two type-II restriction endonucleases have been purified from Lactococ cus lactis subsp. cremoris W9 and W56, the strains isolated from a mix ed Cheddar starter. Their characterization showed that LlnAI was an is oschizomer of MboI from Morexella bovis with the cleaving sequence, 5' -/GATC-3', being sensitive to methylation of the adenine residue; LlnB I was an isoschizomer to SfcI from Streptococcus faecium with the clea ving sequence, 5'-C/TRYAG-3'. Both LlnAI and LlaBI restriction-modific ation (R-M) systems are encoded by the plasmids, respectively, pFW094 and pJW563, protecting the harboring strain against phage attack.