Abstract:
:Electron cryomicroscopy of rotor complexes of the Salmonella typhimurium flagellar motor, overproduced in a nonmotile Escherichia coli host, has revealed a variation in subunit symmetry of the cytoplasmic ring (C ring) module. C rings with subunit symmetries ranging from 31 to 38 were found. They formed a Gaussian distribution around a mean between 34 and 35, a similar number to that determined for native C rings. C-ring diameter scaled with the number of subunits, indicating that the elliptical-shaped subunits maintained constant intersubunit spacing. Taken together with evidence that the M ring does not correspondingly increase in size, this finding indicates that rotor assembly does not require strict stoichiometric interactions between the M- and C-ring subunits. Implications for motor function are discussed.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Young HS,Dang H,Lai Y,DeRosier DJ,Khan Sdoi
10.1016/S0006-3495(03)74877-2subject
Has Abstractpub_date
2003-01-01 00:00:00pages
571-7issue
1eissn
0006-3495issn
1542-0086pii
S0006-3495(03)74877-2journal_volume
84pub_type
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