1. Purification and characterization of plantaricin Y, a novel bacteriocin produced by Lactobacillus plantarum 510
Yi-sheng Chen, Yan-chong Wang, Yiou-shing Chow, Fujitoshi Yanagida, Chen-chung Liao, Chi-ming Chiu Arch Microbiol. 2014 Mar;196(3):193-9. doi: 10.1007/s00203-014-0958-2. Epub 2014 Feb 4.
Lactobacillus plantarum 510, previously isolated from a koshu vineyard in Japan, was found to produce a bacteriocin-like inhibitory substance which was purified and characterized. Mass spectrometry analysis showed that the mass of this bacteriocin is 4,296.65 Da. A partial sequence, NH2- SSSLLNTAWRKFG, was obtained by N-terminal amino acid sequence analysis. A BLAST search revealed that this is a unique sequence; this peptide is thus a novel bacteriocin produced by Lactobacillus plantarum 510 and was termed plantaricin Y. Plantaricin Y shows strong inhibitory activity against Listeria monocytogenes BCRC 14845, but no activity against other pathogens tested. Bacteriocin activity decreased slightly after autoclaving (121 °C for 15 min), but was completely inactivated by protease K. Furthermore, trypsin-digested bacteriocin product fragments retained activity against L. monocytogenes BCRC 14845 and exhibited a different inhibitory spectrum.
2. Isolation and characterization of plantaricin ASM1: a new bacteriocin produced by Lactobacillus plantarum A-1
Tomomi Hata, Rie Tanaka, Sadahiro Ohmomo Int J Food Microbiol. 2010 Jan 31;137(1):94-9. doi: 10.1016/j.ijfoodmicro.2009.10.021. Epub 2009 Nov 10.
Bacteriocins produced by lactic acid bacteria showing stability even in neutral and weak alkaline pH were screened, and a new bacteriocin produced by Lactobacillus plantarum A-1, plantaricin ASM1 (PASM1) was purified and characterized. This bacteriocin which is heat-stable but digested by trypsin inhibits the growth of lactic acid bacterial species, such as Lactobacillus, Leuconostoc, and Enterococcus. PASM1 showed stability in a wide pH range compared to nisin A. The bacteriocin was purified using cation exchange, hydrophobic interaction, and reverse-phase high-performance liquid chromatography. The activity of the purified bacteriocin was obtained as one fraction. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis of the fraction showed a mass of 5045.7Da. Combining the data obtained from amino acid and DNA sequencing, the primary sequence of PASM1 was determined. The sequence of the corresponding gene revealed that the peptide is ribosomally synthesized as a 64 amino acid precursor containing a 21 amino acid N-terminal extension of the double-glycine type. The mature peptide consists of 43 amino acids, which could contain two intramolecular disulfide bonds in the structure. Three putative open reading frames were located upstream of the PLNA1 gene. These genes may encode the thioredoxin family proteins and a response regulator both of which have been suggested to regulate expression of the PASM1 gene and the processing of its leader peptide. PASM1 has no reported homologue bacteriocins. Stability in a wide pH range and heat indicates its potential for application in food preservation.
3. Identification and nucleotide sequence of genes involved in the synthesis of lactocin 705, a two-peptide bacteriocin from Lactobacillus casei CRL 705
S A Cuozzo, F Sesma, J M Palacios, A P de Ruíz Holgado, R R Raya FEMS Microbiol Lett. 2000 Apr 15;185(2):157-61. doi: 10.1111/j.1574-6968.2000.tb09055.x.
The structural gene determinants of lactocin 705, a bacteriocin produced by Lactobacillus casei CRL 705, have been amplified from a plasmid of approximately 35 kb and sequenced. Lactocin 705 is a class IIb bacteriocin, whose activity depends upon the complementation of two peptides (705alpha and 705beta) of 33 amino acid residues each. These peptides are synthesized as precursors with signal sequences of the double-glycine type, which exhibited high identities with the leader peptides of plantaricin S and J from Lactobacillus plantarum, brochocin C from Brochotrix campestris, sakacin P from Lactobacillus sake, and the competence stimulating peptides from Streptococcus gordonii and Streptococcus mitis. However, the two mature bacteriocins 705alpha and 705beta do not show significant similarity to other sequences in the databases.
