The proposal is directed to an understanding of biological processes of energy transduction, switching, structure, and assembly, as exemplified in the bacterial flagellar motor. Wild- type and mutant alleles of selected genes coding for components of the flagellar motor of the bacterium Salmonella typhimurium will be sequenced with a view to determining which regions of the proteins, and which amino acids within those regions, are most critical for various aspects of assembly and function; the proposal builds on a large existing body of detailed classical genetic information. There are three main topics: (i) analysis of the five genes (flaAII.2, flaQ, flaN, motA, and motB) that are known to be involved in energy transduction (conversion of proton potential into mechanical work of rotation) and switching (between counterclockwise and clockwise rotation); (ii) comparison of the structural genes for flagellin, hook protein, and hook-associated proteins in an attempt to discover the basis for their recognition by a flagellar-specific export pathway rather than by the conventional N-terminal signal peptide dependent pathway; (iii) analysis of mutant alleles in the flagellin gene that give rise to failure of assembly or to assembly into abnormal helical polymorphs, with a view to identifying residues that are important in the quasi-equivalent inter-subunit interactions that generate the helicity of the filament. As hypotheses emerge from the mutant sequence analysis, they will be tested by generating site- directed mutations.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM040335-02
Application #
3297771
Study Section
Microbial Physiology and Genetics Subcommittee 2 (MBC)
Project Start
1988-07-01
Project End
1993-06-30
Budget Start
1989-07-01
Budget End
1990-06-30
Support Year
2
Fiscal Year
1989
Total Cost
Indirect Cost
Name
Yale University
Department
Type
Schools of Medicine
DUNS #
082359691
City
New Haven
State
CT
Country
United States
Zip Code
06520
Minamino, T; Yamaguchi, S; Macnab, R M (2000) Interaction between FliE and FlgB, a proximal rod component of the flagellar basal body of Salmonella. J Bacteriol 182:3029-36
Minamino, T; Macnab, R M (2000) Domain structure of Salmonella FlhB, a flagellar export component responsible for substrate specificity switching. J Bacteriol 182:4906-14
Macnab, R M (1999) The bacterial flagellum: reversible rotary propellor and type III export apparatus. J Bacteriol 181:7149-53
Muramoto, K; Makishima, S; Aizawa, S I et al. (1998) Effect of cellular level of FliK on flagellar hook and filament assembly in Salmonella typhimurium. J Mol Biol 277:871-82
Muramoto, K; Macnab, R M (1998) Deletion analysis of MotA and MotB, components of the force-generating unit in the flagellar motor of Salmonella. Mol Microbiol 29:1191-202
Togashi, F; Yamaguchi, S; Kihara, M et al. (1997) An extreme clockwise switch bias mutation in fliG of Salmonella typhimurium and its suppression by slow-motile mutations in motA and motB. J Bacteriol 179:2994-3003
Ohnishi, K; Fan, F; Schoenhals, G J et al. (1997) The FliO, FliP, FliQ, and FliR proteins of Salmonella typhimurium: putative components for flagellar assembly. J Bacteriol 179:6092-9
Toker, A S; Macnab, R M (1997) Distinct regions of bacterial flagellar switch protein FliM interact with FliG, FliN and CheY. J Mol Biol 273:623-34
Williams, A W; Yamaguchi, S; Togashi, F et al. (1996) Mutations in fliK and flhB affecting flagellar hook and filament assembly in Salmonella typhimurium. J Bacteriol 178:2960-70
Toker, A S; Kihara, M; Macnab, R M (1996) Deletion analysis of the FliM flagellar switch protein of Salmonella typhimurium. J Bacteriol 178:7069-79

Showing the most recent 10 out of 23 publications