Suppression by the DNA fragment of the motX promoter region on long flagellar mutants of Vibrio alginolyticus.
The axial length of the polar flagellum (Pof) of Vibrio alginolyticus is about 5 microm. We previously isolated mutants that make abnormally long flagella. The swarm sizes of these mutants in a soft agar plate are smaller than that of a wild-type strain. We cloned a DNA fragment into the pMF209 plasmid that restored the swarming ability of the long-Pof strain V10578. The swimming speed and flagellar length of these transformants were almost equal to the wild-type values. The amounts of PF47 flagellin and PF60 sheath-associated protein, which increased in the long-Pof mutants, were retrieved to almost the wild-type level in the transformants. The plasmid pMF209 contained only a 143 bp chromosomal fragment whose sequence is about 80% similar to that of the motX promoter region of V parahaemolyticus. We speculate that this sequence interacts with a regulatory protein that controls Pof expression. The mutation causing the long-Pof phenotype may be in the gene encoding this protein or in the control region of a structural gene that is regulated by this protein.
Furuno
M
M
Division of Biological Science, Graduate School of Science, Nagoya University, Aichi, Japan.
Nishioka
N
N
Kawagishi
I
I
Homma
M
M
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D015153:Blotting, Western; D003470:Culture Media; D005407:Flagella / Q000502:physiology*; D005408:Flagellin / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism*; D009024:Morphogenesis; D009154:Mutation; D011401:Promoter Regions, Genetic; D014733:Vibrio / Q000235:genetics* / Q000502:physiology / Q000648:ultrastructure
D001426:Bacterial Proteins; D003470:Culture Media; D008565:Membrane Proteins; C089633:MotX protein, bacteria; D005408:Flagellin