Biosynthetic characterization and biochemical features of the third natural nisin variant, nisin Q, produced by Lactococcus lactis 61-14.
OBJECTIVE
To characterize the genetic and biochemical features of nisin Q.


RESULTS
The nisin Q gene cluster was sequenced, and 11 putative orfs having 82% homology with the nisin A biosynthesis gene cluster were identified. Nisin Q production was confirmed from the nisQ-introduced nisin Z producer. In the reporter assay, nisin Q exhibited an induction level that was threefold lower than that of nisin A. Nisin Q demonstrated an antimicrobial spectrum similar to those of the other nisins. Under oxidizing conditions, nisin Q retained a higher level of activity than nisin A. This higher oxidative tolerance could be attributed to the presence of only one methionine residue in nisin Q, in contrast to other nisins that contain two.


CONCLUSIONS
The 11 orfs of the nisin producers were identical with regard to their functions. The antimicrobial spectra of the three natural nisins were similar. Nisin Q demonstrated higher oxidative tolerance than nisin A.


CONCLUSIONS
Genetic and biochemical features of nisin Q are similar to those of other variants. Moreover, owing to its higher oxidative tolerance, nisin Q is a potential alternative for nisin A.
Yoneyama
F
F
Division of Microbial Science and Technology, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Higashi-ku, Fukuoka, Japan.
Fukao
M
M
Zendo
T
T
Nakayama
J
J
Sonomoto
K
K
D000900:Anti-Bacterial Agents / Q000096:biosynthesis* / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D001430:Bacteriocins / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D004269:DNA, Bacterial / Q000235:genetics; D013294:Lactococcus lactis / Q000235:genetics* / Q000378:metabolism; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics; D009561:Nisin / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000235:genetics / Q000494:pharmacology; D016366:Open Reading Frames
D000900:Anti-Bacterial Agents; D001430:Bacteriocins; D004269:DNA, Bacterial; D009561:Nisin