Search tips
Search criteria 


Logo of jbacterPermissionsJournals.ASM.orgJournalJB ArticleJournal InfoAuthorsReviewers
J Bacteriol. 1996 May; 178(10): 2960–2970.
PMCID: PMC178035

Mutations in fliK and flhB affecting flagellar hook and filament assembly in Salmonella typhimurium.


Mutations in the fliK gene of Salmonella typhimurium commonly cause failure to terminate hook assembly and initiate filament assembly (polyhook phenotype). Polyhook mutants give rise to pseudorevertants which are still defective in hook termination but have recovered the ability to assemble filament (polyhook-filament phenotype). The polyhook mutations have been found to be either frameshift or nonsense, resulting in truncation of the C terminus of FliK. Intragenic suppressors of frameshift mutations were found to be ones that restored the original frame (and therefore the C-terminal sequence), but in most cases with substantial loss of natural sequence and sometimes the introduction of artificial sequence; in no cases did intragenic suppression occur when significant disruption remained within the C-terminal region. By use of a novel PCR protocol, in-frame deletions affecting the N-terminal and central regions of FliK were constructed and the resulting phenotypes were examined. Small deletions resulted in almost normal hook length control and almost wild-type swarming. Larger deletions resulted in loss of control of hook length and poor swarming. The largest deletions severely affected filament assembly as well as hook length control. Extragenic suppressors map to an unlinked gene, flhB, which encodes an integral membrane protein (T. Hirano, S. Yamaguchi, K. Oosawa, and S.-I. Aizawa, J. Bacteriol. 176:5439-5449, 1994; K. Kutsukake, T. Minamino, and T. Yokoseki, J. Bacteriol. 176:7625-7629, 1994). They were either point mutations in the C-terminal cytoplasmic region of FlhB or frameshift or nonsense mutations close to the C terminus. The processes of hook and filament assembly and the roles of FliK and FlhB in these processes are discussed in light of these and other available data. We suggest that FliK measures hook length and, at the appropriate point, sends a signal to FlhB to switch the substrate specificity of export from hook protein to late proteins such as flagellin.

Full Text

The Full Text of this article is available as a PDF (1.0M).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Andersen AS, Pettersson AF, Kjeldsen TB. A fast and simple technique for sequencing plasmid DNA with Sequenase using heat denaturation. Biotechniques. 1992 Nov;13(5):678–680. [PubMed]
  • Casanova JL, Pannetier C, Jaulin C, Kourilsky P. Optimal conditions for directly sequencing double-stranded PCR products with sequenase. Nucleic Acids Res. 1990 Jul 11;18(13):4028–4028. [PMC free article] [PubMed]
  • Chen EY, Seeburg PH. Supercoil sequencing: a fast and simple method for sequencing plasmid DNA. DNA. 1985 Apr;4(2):165–170. [PubMed]
  • Eggertsson G, Söll D. Transfer ribonucleic acid-mediated suppression of termination codons in Escherichia coli. Microbiol Rev. 1988 Sep;52(3):354–374. [PMC free article] [PubMed]
  • Engelberg-Kulka H. UGA suppression by normal tRNA Trp in Escherichia coli: codon context effects. Nucleic Acids Res. 1981 Feb 25;9(4):983–991. [PMC free article] [PubMed]
  • Filichkin SA, Gelvin SB. Effect of dimethyl sulfoxide concentration on specificity of primer matching in PCR. Biotechniques. 1992 Jun;12(6):828–830. [PubMed]
  • Gerischer U, Ornston LN. Spontaneous mutations in pcaH and -G, structural genes for protocatechuate 3,4-dioxygenase in Acinetobacter calcoaceticus. J Bacteriol. 1995 Mar;177(5):1336–1347. [PMC free article] [PubMed]
  • Hirano T, Yamaguchi S, Oosawa K, Aizawa S. Roles of FliK and FlhB in determination of flagellar hook length in Salmonella typhimurium. J Bacteriol. 1994 Sep;176(17):5439–5449. [PMC free article] [PubMed]
  • Hirsh D, Gold L. Translation of the UGA triplet in vitro by tryptophan transfer RNA's. J Mol Biol. 1971 Jun 14;58(2):459–468. [PubMed]
  • Homma M, Iino T, Macnab RM. Identification and characterization of the products of six region III flagellar genes (flaAII.3 through flaQII) of Salmonella typhimurium. J Bacteriol. 1988 May;170(5):2221–2228. [PMC free article] [PubMed]
  • Hughes KT, Gillen KL, Semon MJ, Karlinsey JE. Sensing structural intermediates in bacterial flagellar assembly by export of a negative regulator. Science. 1993 Nov 19;262(5137):1277–1280. [PubMed]
  • Katsura I. Determination of bacteriophage lambda tail length by a protein ruler. Nature. 1987 May 7;327(6117):73–75. [PubMed]
  • Katsura I, Hendrix RW. Length determination in bacteriophage lambda tails. Cell. 1984 Dec;39(3 Pt 2):691–698. [PubMed]
  • Kawagishi I, Homma M, Williams AW, Macnab RM. Characterization of the flagellar hook length control protein fliK of Salmonella typhimurium and Escherichia coli. J Bacteriol. 1996 May;178(10):2954–2959. [PMC free article] [PubMed]
  • Kubori T, Shimamoto N, Yamaguchi S, Namba K, Aizawa S. Morphological pathway of flagellar assembly in Salmonella typhimurium. J Mol Biol. 1992 Jul 20;226(2):433–446. [PubMed]
  • Kusukawa N, Uemori T, Asada K, Kato I. Rapid and reliable protocol for direct sequencing of material amplified by the polymerase chain reaction. Biotechniques. 1990 Jul;9(1):66–72. [PubMed]
  • Kutsukake K. Excretion of the anti-sigma factor through a flagellar substructure couples flagellar gene expression with flagellar assembly in Salmonella typhimurium. Mol Gen Genet. 1994 Jun 15;243(6):605–612. [PubMed]
  • Kutsukake K, Minamino T, Yokoseki T. Isolation and characterization of FliK-independent flagellation mutants from Salmonella typhimurium. J Bacteriol. 1994 Dec;176(24):7625–7629. [PMC free article] [PubMed]
  • Labeit S, Gibson T, Lakey A, Leonard K, Zeviani M, Knight P, Wardale J, Trinick J. Evidence that nebulin is a protein-ruler in muscle thin filaments. FEBS Lett. 1991 May 6;282(2):313–316. [PubMed]
  • Macnab RM. Examination of bacterial flagellation by dark-field microscopy. J Clin Microbiol. 1976 Sep;4(3):258–265. [PMC free article] [PubMed]
  • Minamino T, Iino T, Kutuskake K. Molecular characterization of the Salmonella typhimurium flhB operon and its protein products. J Bacteriol. 1994 Dec;176(24):7630–7637. [PMC free article] [PubMed]
  • Nishimura A, Hirota Y. A cell division regulatory mechanism controls the flagellar regulon in Escherichia coli. Mol Gen Genet. 1989 Apr;216(2-3):340–346. [PubMed]
  • Ohnishi K, Ohto Y, Aizawa S, Macnab RM, Iino T. FlgD is a scaffolding protein needed for flagellar hook assembly in Salmonella typhimurium. J Bacteriol. 1994 Apr;176(8):2272–2281. [PMC free article] [PubMed]
  • Patterson-Delafield J, Martinez RJ, Stocker BA, Yamaguchi S. A new fla gene in Salmonella typhimurium--flaR--and its mutant phenotype-superhooks. Arch Mikrobiol. 1973 Mar 26;90(2):107–120. [PubMed]
  • Sanger F, Nicklen S, Coulson AR. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977 Dec;74(12):5463–5467. [PubMed]
  • Sockett H, Yamaguchi S, Kihara M, Irikura VM, Macnab RM. Molecular analysis of the flagellar switch protein FliM of Salmonella typhimurium. J Bacteriol. 1992 Feb;174(3):793–806. [PMC free article] [PubMed]
  • Suzuki T, Iino T. Role of the flaR gene in flagellar hook formation in Salmonella spp. J Bacteriol. 1981 Dec;148(3):973–979. [PMC free article] [PubMed]
  • Tabor S, Richardson CC. DNA sequence analysis with a modified bacteriophage T7 DNA polymerase. Proc Natl Acad Sci U S A. 1987 Jul;84(14):4767–4771. [PubMed]
  • Woo TH, Cheng AF, Ling JM. An application of a simple method for the preparation of bacterial DNA. Biotechniques. 1992 Nov;13(5):696–698. [PubMed]
  • Yamaguchi S, Fujita H, Ishihara A, Aizawa S, Macnab RM. Subdivision of flagellar genes of Salmonella typhimurium into regions responsible for assembly, rotation, and switching. J Bacteriol. 1986 Apr;166(1):187–193. [PMC free article] [PubMed]

Articles from Journal of Bacteriology are provided here courtesy of American Society for Microbiology (ASM)