1. Cloning and nucleotide sequence of the gene for acidocin 8912, a bacteriocin from Lactobacillus acidophilus TK8912
K Kanatani, T Tahara, M Oshimura, K Sano, C Umezawa Lett Appl Microbiol. 1995 Dec;21(6):384-6. doi: 10.1111/j.1472-765x.1995.tb01087.x.
Acidocin 8912 is a bacteriocin produced by Lactobacillus acidophilus TK8912. The acidocin 8912 structural gene, acdT, was cloned and determined. It was located on the 14-kb plasmid pL103 and encoded a 46 amino acid precursor including a 20 amino acid N-terminal extension. The precursor sequence of the acdT gene shows a conservation of the general structural characteristics of the bacteriocin precursors from some lactic acid bacteria.
2. Plasmid-associated Bacteriocin Production by and Immunity of Lactobacillus acidophilus TK8912
K Kanatani, T Tahara, K Yoshida, H Miura, M Sakamoto, M Oshimura Biosci Biotechnol Biochem. 1992 Jan;56(4):648-51. doi: 10.1271/bbb.56.648.
Lactobacillus acidophilus TK8912 produces an antibacterial substance, designated acidocin 8912, which is active against strains of Lactobacillus and Lactococcus. Of all conditions tested, the production of acidocin 8912 was maximum at 30°C in MRS broth. Acidocin 8912 was stable to heat treatment (120°C for 20min), but completely inactivated by protease treatment. Curing a plasmid pLA103 resulted in the loss of both acidocin 8912 production (Acd(+)) and host immunity (Acd(r)). A plasmid-cured strain, TK1-4 (Acd(-) Acd(8)), was transformed to Acd(+)Acd(r) with the pLA103 plasmid. These results provided the first direct evidence in lactobacilli for involvement of this plasmid in bacteriocin production and immunity.
3. Purification and some properties of acidocin 8912, a novel bacteriocin produced by Lactobacillus acidophilus TK8912
T Tahara, K Kanatani, K Yoshida, H Miura, M Sakamoto, M Oshimura Biosci Biotechnol Biochem. 1992 Aug;56(8):1212-5. doi: 10.1271/bbb.56.1212.
Acidocin 8912, a bacteriocin produced by Lactobacillus acidophilus TK8912, was purified by ammonium sulfate fractionation and successive chromatographies on CM-cellulose, Sephadex G-50, Sephadex G-25, and reversed-phase HPLC on Aquapore RP-300. The purified acidocin 8912 migrated as a single band on SDS-PAGE. The molecular weight was estimated to be 5200 by SDS-PAGE, and 5400 by HPLC gel filtration on TSKgel G3000PWXL. Both the amino acid composition and the N-terminal amino acid sequence analysis indicated that acidocin 8912 was a peptide composed of presumably 50 amino acids containing a Lys residue at the N-terminus. The purified acidocin 8912 showed a bactericidal effect on sensitive cells but not a bacteriolytic effect.
