Characterization and structure analysis of a novel bacteriocin, lacticin Z, produced by Lactococcus lactis QU 14.
A novel bacteriocin, lacticin Z, produced by Lactococcus lactis QU 14 isolated from a horse's intestinal tract was identified. Lacticin Z was purified through a three step procedure comprised of hydrophobic-interaction, cation-exchange chromatography, and reverse-phase HPLC. ESI-TOF MS determined the molecular mass of lacticin Z to be 5,968.9 Da. The primary structure of lacticin Z was found to consist of 53 amino acid residues without any leader sequence or signal peptide. Lacticin Z showed homology to lacticin Q from L. lactis QU 5, aureocin A53 from Staphylococcus aureus A53, and mutacin BHT-B from Streptococcus rattus strain BHT. It exhibited a nanomolar range of MICs against various Gram-positive bacteria, and the activity was completely stable up to 100 degrees C. Unlike many of other LAB bacteriocins, the stability of lacticin Z was emphasized under alkaline conditions rather than acidic conditions. All the results indicated that lacticin Z belongs to a novel type of bacteriocin.
Iwatani
Shun
S
Laboratory of Microbial Technology, Division of Microbial Science and Technology, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Hakozaki, Fukuoka, Japan.
Zendo
Takeshi
T
Yoneyama
Fuminori
F
Nakayama
Jiro
J
Sonomoto
Kenji
K
D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins; D001430:Bacteriocins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D002845:Chromatography; D006094:Gram-Positive Bacteria / Q000187:drug effects; D006736:Horses; D013294:Lactococcus lactis / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D017386:Sequence Homology, Amino Acid; D021241:Spectrometry, Mass, Electrospray Ionization
D001426:Bacterial Proteins; D001430:Bacteriocins; C524970:lacticin Z, Lactococcus lactis