Research Of Cryptic Plasmid In Lactic Acid Bacteria

Lactic acid bacteria are widely distributed in the nature. The genus Lactobacillus,Lactococcus, Pediococcus and Leuconostoc are included being representatives in this group. Thelactic acid fermentation, which these bacteria perform has long been known and applied by thehumans for making different foodstuffs. The wild strains, in biotechnological aspect areperspective as bacteriocin producer and probiotics. They have a potential use for the establishingof new, the so-called "functional foods". With the research going deeply, we find there are a lotof important physiologic function concerned with the plasmids in Lactic acid bacteria. So it theresearch about the cryptic plasmids is important to organize molecular cloning system andimprove the character of Lactic acid bacteria. Now there are many more laws to confine geneticengineering technology, though genetic engineering technology can improve the food and drugindustry. The genetic engineering technology need have development in food-grade, because themolecular cloning system of food-grade must make from the same kind or organism of GRASwithout antibiotics-mark. To prevent the migration of plasmids to harmful-flora which beimproved, we can not use plasmids with functionality. For the stabilization of plasmids, weshould choose ?-style replication plasmids.The study is using Takara plasmids-abstraction kit to abstract the DNA of plasmids afterbroke the cell-wall of Lactic acid bacteria. Then I choose a Lactic acid bacteria after analysis theDNA of plasmids with the electrophoregram and choose a suitable cryptic plasmid according toattribute of genetic engineering vehicle. Last I analysis the way of reproduction on pBL102 bySouthern bloting to be sure that the way of reproduction. The novel methods include: abstractionof DNA of plasmids in Lactic acid bacteria, analysis of the electrophoregram of DNA ofplasmids, recovery the plasmid, analyzed the DNA of plasmids of cutting on enzyme, analysisthe way of reproduction on the plasmid by Southern bloting.I abstract the DNA of plasmids after broking the cell-wall of 21 Lactic acid bacteria withTakara plasmids-abstraction kit, then analysis and comparison. I choose L12 to analysis. Aftercomparison the plasmids in L12 choose plasmid pBL102. Draw enzyme-cut atlas after cuttingpBL102 with Kpnâ… ,EcoRâ… ,Pstâ… ,BamHâ… ,Sacâ… . Analysis pBL102 using Southern bloting, thenbe sure the reproduction of plasmid which is?.