POSTERS - BLAST X - University of Utah

BLAST X Poster #33
CHARACTERIZATIONS OF THE PSEUDOREVERTANTS FROM SALMONELLA
TYPHIMURIUM STRAIN SJW1655 AND SJW1660 WITH THE R- AND THE L-TYPE
STRAIGHT FLAGELLAR FILAMENTS
Hidetoshi Tomaru, Fumio Hayashi, Eiji Furukawa, Shigeru Yamaguchi & Kenji Oosawa
Department of Chemistry and Chemical Biology, Graduate School of Engineering, Gunma
University, 1-5-1 Tenjin, Kiryu, Gunma 376-8515, JAPAN
A cell of Salmonella typhimurium swims by rotating its flagellar filaments. A wild-type
cell carries a left-handed helical filament that is called a normal filament. On the other hand,
various mutants carrying different helical shapes were isolated. There are curly, coiled, semicoiled
and two kinds, L- and R-types, of straight filaments known. Transformations of filament
helical shape among normal, semi-coiled and curly were observed during tumbling of the cell.
To investigate the transformation mechanism of flagellar filaments, we isolated 95 revertants,
which recovered their swarming abilities, from Salmonella typhimurium strain SJW1655 with the
R-type straight flagellar filament. The numbers of the pseudorevertants carrying another
mutation site were 64 and the second mutation sites were 4. Similarly, we isolated 106
revertants (including 101 pseudorevertants) from SJW1660 (the L-type straight flagellar
filament). The numbers of the second mutation sites were 19. We also measured the swimming
speeds of the pseudorevertants and observed the flagellar shapes isolated from the
pseudorevertants. We will discuss, in this meeting, the differences in the distribution of the
second mutation sites, the swimming speeds, and the flagellar shapes of the pseudorevertants
from between SJW1655 and SJW1660.
84