Gene Symbol: yajC
Description: SecYEG protein translocase auxillary subunit
Alias: ECK0401, JW0397
Species: Escherichia coli str. K-12 substr. MG1655

Top Publications

  1. Pogliano J, Beckwith J. SecD and SecF facilitate protein export in Escherichia coli. EMBO J. 1994;13:554-61 pubmed
    ..Our results provide additional support for the notion that an early step in protein export is cold-sensitive. ..
  2. Törnroth Horsefield S, Gourdon P, Horsefield R, Brive L, Yamamoto N, Mori H, et al. Crystal structure of AcrB in complex with a single transmembrane subunit reveals another twist. Structure. 2007;15:1663-73 pubmed
    ..the X-ray structure of AcrB in complex with a single transmembrane protein, assigned by mass spectrometry as YajC. A specific rotation of the periplasmic porter domain of AcrB is also revealed, consistent with the hypothesized &..
  3. van der Sluis E, Driessen A. Stepwise evolution of the Sec machinery in Proteobacteria. Trends Microbiol. 2006;14:105-8 pubmed
    ..The Sec machinery of Escherichia coli and other Enterobacteriales represents the end product of this stepwise evolution. ..
  4. Fang J, Wei Y. Expression, purification and characterization of the Escherichia coli integral membrane protein YajC. Protein Pept Lett. 2011;18:601-8 pubmed
    Escherichia coli YajC is a small integral membrane protein with a single transmembrane helix. The gene yajC is part of the secD operon and the protein is identified in the SecDF-YajC complex...
  5. Duong F, Wickner W. The SecDFyajC domain of preprotein translocase controls preprotein movement by regulating SecA membrane cycling. EMBO J. 1997;16:4871-9 pubmed
    ..coli preprotein translocase comprises a membrane-embedded hexameric complex of SecY, SecE, SecG, SecD, SecF and YajC (SecYEGDFyajC) and the peripheral ATPase SecA...
  6. Samuelson J, Chen M, Jiang F, Moller I, Wiedmann M, Kuhn A, et al. YidC mediates membrane protein insertion in bacteria. Nature. 2000;406:637-41 pubmed
    ..These results provide evidence for an additional component of the translocation machinery that is specialized for the integration of membrane proteins...
  7. Duong F, Wickner W. Distinct catalytic roles of the SecYE, SecG and SecDFyajC subunits of preprotein translocase holoenzyme. EMBO J. 1997;16:2756-68 pubmed
    ..The proteins encoded by the secD operon--SecD, SecF and YajC--also form an integral membrane heterotrimeric complex (SecDFyajC)...
  8. Danese P, Silhavy T. Targeting and assembly of periplasmic and outer-membrane proteins in Escherichia coli. Annu Rev Genet. 1998;32:59-94 pubmed
    ..We also discuss the various signal transduction systems that monitor extracytoplasmic protein folding and targeting, and we consider how these signal transduction systems may ultimately control these processes. ..
  9. Kedrov A, Kusters I, Krasnikov V, Driessen A. A single copy of SecYEG is sufficient for preprotein translocation. EMBO J. 2011;30:4387-97 pubmed publisher
    ..These data imply that the SecYEG monomer is sufficient to form a functional translocon in the lipid membrane. ..

More Information


  1. Durand J, Okada N, Tobe T, Watarai M, Fukuda I, Suzuki T, et al. vacC, a virulence-associated chromosomal locus of Shigella flexneri, is homologous to tgt, a gene encoding tRNA-guanine transglycosylase (Tgt) of Escherichia coli K-12. J Bacteriol. 1994;176:4627-34 pubmed
    ..coli strains, consistent with the hypothesis that the vacC (tgt) gene contributes to the pathogenicity of Shigella flexneri. ..
  2. Gardel C, Johnson K, Jacq A, Beckwith J. The secD locus of E.coli codes for two membrane proteins required for protein export. EMBO J. 1990;9:3209-16 pubmed
    ..We suggest that these two proteins may form a complex in the membrane which acts at late steps in the export process. ..
  3. Nouwen N, Driessen A. Inactivation of protein translocation by cold-sensitive mutations in the yajC-secDF operon. J Bacteriol. 2005;187:6852-5 pubmed
    Most mutations in the yajC-secDF operon identified via genetic screens confer a cold-sensitive growth phenotype...
  4. Luirink J, von Heijne G, Houben E, de Gier J. Biogenesis of inner membrane proteins in Escherichia coli. Annu Rev Microbiol. 2005;59:329-55 pubmed
    ..This review deals mainly with recent structural and biochemical data from various experimental systems that offer new insight into the different stages of biogenesis of E. coli IMPs. ..
  5. Gardel C, Benson S, Hunt J, Michaelis S, Beckwith J. secD, a new gene involved in protein export in Escherichia coli. J Bacteriol. 1987;169:1286-90 pubmed
    ..A plasmid carrying secD+ was identified and used to show that the mutations are recessive. The secD gene may code for a component of the cellular export machinery. ..
  6. Nouwen N, van der Laan M, Driessen A. SecDFyajC is not required for the maintenance of the proton motive force. FEBS Lett. 2001;508:103-6 pubmed
    ..The expression of this enzyme complex is repressed by growth on glucose media, the condition used to deplete SecDFyajC. These results demonstrate that SecDFyajC is not required for proton motive force-driven protein translocation...
  7. Reuter K, Slany R, Ullrich F, Kersten H. Structure and organization of Escherichia coli genes involved in biosynthesis of the deazaguanine derivative queuine, a nutrient factor for eukaryotes. J Bacteriol. 1991;173:2256-64 pubmed
    ..The organization of the promoter sequences and the termination sites suggests that queA, tgt, and ORF 12 are localized on a putative operon together with the genes secD and secF. ..
  8. Pogliano K, Beckwith J. Genetic and molecular characterization of the Escherichia coli secD operon and its products. J Bacteriol. 1994;176:804-14 pubmed
    ..We have characterized this operon, and found that, in addition to secD and secF, it contains the upstream gene yajC, but not the genes queA or tgt, in contrast to previous reports...
  9. Nouwen N, Driessen A. SecDFyajC forms a heterotetrameric complex with YidC. Mol Microbiol. 2002;44:1397-405 pubmed
    ..SecD, SecF, and YajC form another heterotrimeric complex that can associate with the SecYEG complex...
  10. Mao C, Cheadle C, Hardy S, Lilly A, Suo Y, Sanganna Gari R, et al. Stoichiometry of SecYEG in the active translocase of Escherichia coli varies with precursor species. Proc Natl Acad Sci U S A. 2013;110:11815-20 pubmed publisher
    ..The active translocase for the precursor of periplasmic galactose-binding protein contains twice the number of heterotrimeric units of SecYEG as does that for the precursor of outer membrane protein A. ..
  11. Taura T, Akiyama Y, Ito K. Genetic analysis of SecY: additional export-defective mutations and factors affecting their phenotypes. Mol Gen Genet. 1994;243:261-9 pubmed
    ..Overexpression of "yajC", located within the secD operon, suppressed secY-d1...
  12. Prabudiansyah I, Kusters I, Caforio A, Driessen A. Characterization of the annular lipid shell of the Sec translocon. Biochim Biophys Acta. 2015;1848:2050-6 pubmed publisher
    ..Such lipid enrichment was not found with separately extracted SecDFyajC or YidC, which demonstrates a specific interaction between SecYEG and negatively charged lipids. ..
  13. Kato Y, Nishiyama K, Tokuda H. Depletion of SecDF-YajC causes a decrease in the level of SecG: implication for their functional interaction. FEBS Lett. 2003;550:114-8 pubmed
    SecA and an apparatus comprising SecYEG and SecDF-YajC complexes catalyze protein translocation across the Escherichia coli membrane...
  14. Muller M, Koch H, Beck K, Schafer U. Protein traffic in bacteria: multiple routes from the ribosome to and across the membrane. Prog Nucleic Acid Res Mol Biol. 2001;66:107-57 pubmed
    ..into the SecYE translocon, a process that is strongly assisted by a couple of membrane proteins, SecG, SecD, SecF, YajC, and the proton gradient across the membrane...
  15. Scotti P, Urbanus M, Brunner J, de Gier J, von Heijne G, van der Does C, et al. YidC, the Escherichia coli homologue of mitochondrial Oxa1p, is a component of the Sec translocase. EMBO J. 2000;19:542-9 pubmed
    ..Previous work has also identified the peripherally associated SecA protein as well as the SecD, SecF and YajC inner membrane proteins as components of the translocase...