Gene Symbol: ffh
Description: Signal Recognition Particle (SRP) component with 4.5S RNA (ffs)
Alias: ECK2607, JW5414
Species: Escherichia coli str. K-12 substr. MG1655

Top Publications

  1. 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
    ..between their noncleaved signal anchor sequences and the bacterial signal recognition particle (SRP) consisting of Ffh and 4.5S RNA...
  2. Lee H, Bernstein H. The targeting pathway of Escherichia coli presecretory and integral membrane proteins is specified by the hydrophobicity of the targeting signal. Proc Natl Acad Sci U S A. 2001;98:3471-6 pubmed
    ..These results imply that different classes of E. coli proteins are targeted by distinct pathways because bacterial SRP binds to a more restricted range of targeting signals than its eukaryotic counterpart...
  3. Raine A, Ullers R, Pavlov M, Luirink J, Wikberg J, Ehrenberg M. Targeting and insertion of heterologous membrane proteins in E. coli. Biochimie. 2003;85:659-68 pubmed
    ..coli membrane proteins. No significant pausing of protein elongation was observed in the presence of E. coli SRP, in line with the suggestion that translational arrest requires an Alu domain, which is absent in SRP from E. coli. ..
  4. Beck K, Wu L, Brunner J, Muller M. Discrimination between SRP- and SecA/SecB-dependent substrates involves selective recognition of nascent chains by SRP and trigger factor. EMBO J. 2000;19:134-43 pubmed
  5. Ullers R, Houben E, Raine A, ten Hagen Jongman C, Ehrenberg M, Brunner J, et al. Interplay of signal recognition particle and trigger factor at L23 near the nascent chain exit site on the Escherichia coli ribosome. J Cell Biol. 2003;161:679-84 pubmed
    ..The results suggest a role for L23 in the targeting of IMPs as an attachment site for TF and SRP that is close to the emerging nascent chain. ..
  6. Peluso P, Shan S, Nock S, Herschlag D, Walter P. Role of SRP RNA in the GTPase cycles of Ffh and FtsY. Biochemistry. 2001;40:15224-33 pubmed
    The bacterial homologues of the signal recognition particle (SRP) and its receptor, the Ffh*4...
  7. Shan S, Stroud R, Walter P. Mechanism of association and reciprocal activation of two GTPases. PLoS Biol. 2004;2:e320 pubmed
    ..During this process, two GTPases, one in SRP and one in the SRP receptor (named Ffh and FtsY in bacteria, respectively), form a complex in which both proteins reciprocally activate the GTPase ..
  8. Batey R, Rambo R, Lucast L, Rha B, Doudna J. Crystal structure of the ribonucleoprotein core of the signal recognition particle. Science. 2000;287:1232-9 pubmed
    ..The structure explains why the conserved residues in the protein and RNA are required for SRP assembly and defines a signal sequence recognition surface composed of both protein and RNA. ..
  9. Bernstein H, Poritz M, Strub K, Hoben P, Brenner S, Walter P. Model for signal sequence recognition from amino-acid sequence of 54K subunit of signal recognition particle. Nature. 1989;340:482-6 pubmed
    ..We propose that SRP54 and SR alpha use GTP in sequential steps of the targeting reaction and that essential features of such a pathway are conserved from bacteria to mammals. ..

More Information


  1. de Gier J, Luirink J. Biogenesis of inner membrane proteins in Escherichia coli. Mol Microbiol. 2001;40:314-22 pubmed
    ..Here, we review and discuss recent advances in our understanding of the biogenesis of inner membrane proteins in E. coli. ..
  2. Luirink J, High S, Wood H, Giner A, Tollervey D, Dobberstein B. Signal-sequence recognition by an Escherichia coli ribonucleoprotein complex. Nature. 1992;359:741-3 pubmed
    ..5S RNA and P48 protein (Ffh) of Escherichia coli which form a ribonucleoprotein particle. Depletion of 4...
  3. Herskovits A, Bochkareva E, Bibi E. New prospects in studying the bacterial signal recognition particle pathway. Mol Microbiol. 2000;38:927-39 pubmed
    ..The bacterial SRP system consists of at least two proteins and an RNA molecule (termed Ffh, FtsY and 4.5S RNA, respectively, in Escherichia coli)...
  4. Koch H, Hengelage T, Neumann Haefelin C, Macfarlane J, Hoffschulte H, Schimz K, et al. In vitro studies with purified components reveal signal recognition particle (SRP) and SecA/SecB as constituents of two independent protein-targeting pathways of Escherichia coli. Mol Biol Cell. 1999;10:2163-73 pubmed
    ..was simultaneously rendered deficient in SecA/SecB and the signal recognition particle (SRP) components, Ffh (P48), 4. 5S RNA, and FtsY. The integration of two membrane proteins into inside-out plasma membrane vesicles of E...
  5. Jagath J, Rodnina M, Lentzen G, Wintermeyer W. Interaction of guanine nucleotides with the signal recognition particle from Escherichia coli. Biochemistry. 1998;37:15408-13 pubmed
    ..In Escherichia coli, the particle consists of a 114 nt RNA, a 4.5S RNA, and a 48 kDa GTP-binding protein, Ffh. GDP-GTP exchange on, and GTP hydrolysis by, Ffh are thought to regulate SRP function in membrane targeting of ..
  6. Bernstein H, Hyndman J. Physiological basis for conservation of the signal recognition particle targeting pathway in Escherichia coli. J Bacteriol. 2001;183:2187-97 pubmed
    ..coli and possibly conserved throughout prokaryotic evolution as well partly because efficient IMP targeting prevents a toxic accumulation of aggregated proteins in the cytoplasm. ..
  7. Ulbrandt N, Newitt J, Bernstein H. The E. coli signal recognition particle is required for the insertion of a subset of inner membrane proteins. Cell. 1997;88:187-96 pubmed
    ..coli preproteins and some IMPs can utilize SRP-independent targeting pathways effectively, the structural features of a subset of IMPs have required the conservation of an SRP-based targeting machinery. ..
  8. Lu Y, Qi H, Hyndman J, Ulbrandt N, Teplyakov A, Tomasevic N, et al. Evidence for a novel GTPase priming step in the SRP protein targeting pathway. EMBO J. 2001;20:6724-34 pubmed
    ..of the SRP pathway GTPases, we mutated an invariant glycine in Escherichia coli SRP54 and SRalpha orthologs ('Ffh' and 'FtsY', respectively) that resides at the N-GTPase domain interface...
  9. Jensen C, Pedersen S. Concentrations of 4.5S RNA and Ffh protein in Escherichia coli: the stability of Ffh protein is dependent on the concentration of 4.5S RNA. J Bacteriol. 1994;176:7148-54 pubmed
    We measured the concentrations of both 4.5S RNA and Ffh protein under a variety of growth conditions and found that there were 400 molecules of 4...
  10. Bowers C, Lau F, Silhavy T. Secretion of LamB-LacZ by the signal recognition particle pathway of Escherichia coli. J Bacteriol. 2003;185:5697-705 pubmed
    ..Secretion of this hydrophobic fusion variant (H*LamB-LacZ) was reduced in the absence of fully functional Ffh and Ffs, and the translocator jamming caused by Hyb42-1 was prevented by efficient delivery of the fusion to the ..
  11. 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. ..
  12. Powers T, Walter P. Reciprocal stimulation of GTP hydrolysis by two directly interacting GTPases. Science. 1995;269:1422-4 pubmed
    The Escherichia coli guanosine triphosphate (GTP)-binding proteins Ffh and FtsY have been proposed to catalyze the cotranslational targeting of proteins to the bacterial plasma membrane...
  13. Yosef I, Bochkareva E, Adler J, Bibi E. Membrane protein biogenesis in Ffh- or FtsY-depleted Escherichia coli. PLoS ONE. 2010;5:e9130 pubmed publisher
    ..SRP) system is required for biogenesis of membrane proteins and contains two essential proteins: the SRP subunit Ffh and the SRP-receptor FtsY...
  14. Zheng N, Gierasch L. Domain interactions in E. coli SRP: stabilization of M domain by RNA is required for effective signal sequence modulation of NG domain. Mol Cell. 1997;1:79-87 pubmed
    ..5S RNA. Signal peptide binding to isolated NG domain also causes a pronounced destabilization, implicating the NG domain in direct recognition of signal peptide. ..
  15. de Gier J, Scotti P, Saaf A, Valent Q, Kuhn A, Luirink J, et al. Differential use of the signal recognition particle translocase targeting pathway for inner membrane protein assembly in Escherichia coli. Proc Natl Acad Sci U S A. 1998;95:14646-51 pubmed
    ..in vitro and in Escherichia coli strains that are conditional for the expression of either the 54 homologue (Ffh) or 4.5S RNA, which are the two components of the E...
  16. Römisch K, Webb J, Herz J, Prehn S, Frank R, Vingron M, et al. Homology of 54K protein of signal-recognition particle, docking protein and two E. coli proteins with putative GTP-binding domains. Nature. 1989;340:478-82 pubmed
    ..Significant sequence homology was found to part of DP alpha and two E. coli proteins of unknown function. The homologous region includes a putative GTP-binding domain. ..
  17. Houben E, Zarivach R, Oudega B, Luirink J. Early encounters of a nascent membrane protein: specificity and timing of contacts inside and outside the ribosome. J Cell Biol. 2005;170:27-35 pubmed
    ..Intraribosomal contacts of the nascent chain were not influenced by the presence of a functional TM in the ribosome. ..
  18. Valent Q, de Gier J, von Heijne G, Kendall D, Ten Hagen Jongman C, Oudega B, et al. Nascent membrane and presecretory proteins synthesized in Escherichia coli associate with signal recognition particle and trigger factor. Mol Microbiol. 1997;25:53-64 pubmed
    ..coli ribosome. ..
  19. Ullers R, Houben E, Brunner J, Oudega B, Harms N, Luirink J. Sequence-specific interactions of nascent Escherichia coli polypeptides with trigger factor and signal recognition particle. J Biol Chem. 2006;281:13999-4005 pubmed
    ..Importantly and in contrast to published data, the SRP appears perfectly capable of distinguishing SA sequences from signal sequences in secretory proteins at this early stage in biogenesis. ..
  20. Egea P, Shan S, Napetschnig J, Savage D, Walter P, Stroud R. Substrate twinning activates the signal recognition particle and its receptor. Nature. 2004;427:215-21 pubmed
    ..This unique circle of twinned interactions is severed twice on hydrolysis, leading to complex dissociation after cargo delivery...
  21. Angelini S, Deitermann S, Koch H. FtsY, the bacterial signal-recognition particle receptor, interacts functionally and physically with the SecYEG translocon. EMBO Rep. 2005;6:476-81 pubmed
    ..We now provide evidence for the direct interaction between FtsY and the SecY translocon. This interaction offers an explanation of how the bacterial SRP cycle is regulated in response to available translocation channels. ..
  22. Schierle C, Berkmen M, Huber D, Kumamoto C, Boyd D, Beckwith J. The DsbA signal sequence directs efficient, cotranslational export of passenger proteins to the Escherichia coli periplasm via the signal recognition particle pathway. J Bacteriol. 2003;185:5706-13 pubmed
    ..Finally, probably because of its rapid folding in the cytoplasm, thioredoxin provides, along with gene fusion approaches, a sensitive assay system for signal sequences that utilize the SRP pathway. ..
  23. Powers T, Walter P. Co-translational protein targeting catalyzed by the Escherichia coli signal recognition particle and its receptor. EMBO J. 1997;16:4880-6 pubmed
    The Ffh-4.5S ribonucleoprotein particle (RNP) and FtsY from Escherichia coli are homologous to essential components of the mammalian signal recognition particle (SRP) and SRP receptor, respectively. The ability of these E...
  24. de Gier J, Mansournia P, Valent Q, Phillips G, Luirink J, von Heijne G. Assembly of a cytoplasmic membrane protein in Escherichia coli is dependent on the signal recognition particle. FEBS Lett. 1996;399:307-9 pubmed
    ..to the wild-type protein was studied in Escherichia coli strains that are conditional for the expression of either Ffh or 4.5S RNA, the two components of the E. coli SRP...
  25. Park S, Jiang F, Dalbey R, Phillips G. Functional analysis of the signal recognition particle in Escherichia coli by characterization of a temperature-sensitive ffh mutant. J Bacteriol. 2002;184:2642-53 pubmed
    The Ffh protein of Escherichia coli is a 48-kDa polypeptide that is homologous to the SRP54 subunit of the eukaryotic signal recognition particle (SRP)...
  26. Peluso P, Herschlag D, Nock S, Freymann D, Johnson A, Walter P. Role of 4.5S RNA in assembly of the bacterial signal recognition particle with its receptor. Science. 2000;288:1640-3 pubmed
    ..In Escherichia coli, this reaction is mediated by the Ffh/4.5S RNA ribonucleoprotein complex (Ffh/4.5S RNP; the SRP) and the FtsY protein (the SRP receptor)...
  27. Peterson J, Woolhead C, Bernstein H. Basic amino acids in a distinct subset of signal peptides promote interaction with the signal recognition particle. J Biol Chem. 2003;278:46155-62 pubmed
    ..Taken together, the data suggest that the formation of salt bridges between SRP RNA and basic amino acids facilitates the binding of a distinct subset of signal peptides whose hydrophobicity falls slightly below a threshold level. ..
  28. Bornemann T, Jöckel J, Rodnina M, Wintermeyer W. Signal sequence-independent membrane targeting of ribosomes containing short nascent peptides within the exit tunnel. Nat Struct Mol Biol. 2008;15:494-9 pubmed publisher
  29. Gu S, Peske F, Wieden H, Rodnina M, Wintermeyer W. The signal recognition particle binds to protein L23 at the peptide exit of the Escherichia coli ribosome. RNA. 2003;9:566-73 pubmed
    The signal recognition particle (SRP) from Escherichia coli, composed of Ffh protein and 4.5S RNA, mediates membrane targeting of translating ribosomes displaying a signal or signal-anchor sequence...
  30. Tian H, Beckwith J. Genetic screen yields mutations in genes encoding all known components of the Escherichia coli signal recognition particle pathway. J Bacteriol. 2002;184:111-8 pubmed
    ..coli signal recognition particle pathway: ffh, ffs, and ftsY, which encode Ffh, 4.5S RNA, and FtsY, respectively...
  31. Avdeeva O, Myasnikov A, Sergiev P, Bogdanov A, Brimacombe R, Dontsova O. Construction of the 'minimal' SRP that interacts with the translating ribosome but not with specific membrane receptors in Escherichia coli. FEBS Lett. 2002;514:70-3 pubmed
    Escherichia coli signal recognition particle (SRP) consists of 4.5S RNA and Ffh protein. In contrast to eukaryotes, it remains unclear whether translation arrest takes place in prokaryotic cells...
  32. Rinke Appel J, Osswald M, von Knoblauch K, Mueller F, Brimacombe R, Sergiev P, et al. Crosslinking of 4.5S RNA to the Escherichia coli ribosome in the presence or absence of the protein Ffh. RNA. 2002;8:612-25 pubmed
    ..The ability of this modified 4.5S RNA to form a complex with the protein Ffh was demonstrated by a gel shift assay. The modified 4...
  33. Macfarlane J, Muller M. The functional integration of a polytopic membrane protein of Escherichia coli is dependent on the bacterial signal-recognition particle. Eur J Biochem. 1995;233:766-71 pubmed
    ..5S RNA (Ffs) and 7SL RNA, and (b) the E. coli P48 (Ffh) and SRP 54-kDa subunit, more evidence has been obtained that E...
  34. Kim J, Rusch S, Luirink J, Kendall D. Is Ffh required for export of secretory proteins?. FEBS Lett. 2001;505:245-8 pubmed
    ..We show that depletion of SRP, but not trigger factor, affects all the mutants examined. These results suggest secretory proteins with a variety of signal sequences, as well as membrane proteins, require SRP for export. ..
  35. Moser C, Mol O, Goody R, Sinning I. The signal recognition particle receptor of Escherichia coli (FtsY) has a nucleotide exchange factor built into the GTPase domain. Proc Natl Acad Sci U S A. 1997;94:11339-44 pubmed
    ..In E. coli SRP consists of only one polypeptide (Ffh), and a 4.5S RNA...
  36. Tian H, Boyd D, Beckwith J. A mutant hunt for defects in membrane protein assembly yields mutations affecting the bacterial signal recognition particle and Sec machinery. Proc Natl Acad Sci U S A. 2000;97:4730-5 pubmed
    ..Although both the ffs and the secA locus mutations interfere with membrane protein assembly, only the latter also reduces export of a protein containing a cleavable signal sequence. ..
  37. Buskiewicz I, Jöckel J, Rodnina M, Wintermeyer W. Conformation of the signal recognition particle in ribosomal targeting complexes. RNA. 2009;15:44-54 pubmed publisher
    ..Here we probe the conformation of SRP and SRP protein, Ffh, at different stages of targeting by measuring fluorescence resonance energy transfer (FRET) between fluorophores ..
  38. Lentzen G, Dobberstein B, Wintermeyer W. Formation of SRP-like particle induces a conformational change in E. coli 4.5S RNA. FEBS Lett. 1994;348:233-8 pubmed
    ..From equilibrium titrations with fluorescent 4.5S RNA, a dissociation constant of 0.15 microns is obtained for the RNA.protein complex. The formation of the complex is not affected by GTP binding to or hydrolysis by P48. ..
  39. Bernstein H, Zopf D, Freymann D, Walter P. Functional substitution of the signal recognition particle 54-kDa subunit by its Escherichia coli homolog. Proc Natl Acad Sci U S A. 1993;90:5229-33 pubmed
    ..J. & Silhavy, T. J. (1992) Nature (London) 359, 744-746] have shown that depletion of this protein, designated Ffh (fifty-four homolog), leads to a significant secretory defect in vivo...
  40. Brunelli C, O Connor M, Dahlberg A. Decreased requirement for 4.5S RNA in 16S and 23S rRNA mutants of Escherichia coli. FEBS Lett. 2002;514:44-8 pubmed
    ..at C732 in 16S rRNA and at A1668 and G1423 in 23S rRNA altered the cellular responses to decreases in both Ffh (the bacterial homolog of SRP54) and 4...
  41. Miller J, Bernstein H, Walter P. Interaction of E. coli Ffh/4.5S ribonucleoprotein and FtsY mimics that of mammalian signal recognition particle and its receptor. Nature. 1994;367:657-9 pubmed
    ..Two proteins from Escherichia coli, Ffh and FTsY, structurally resemble SRP54 and SR alpha...
  42. Samuelsson T, Olsson M, Wikström P, Johansson B. The GTPase activity of the Escherichia coli Ffh protein is important for normal growth. Biochim Biophys Acta. 1995;1267:83-91 pubmed
    The Escherichia coli (E. coli) Ffh protein is homologous to the 54kDa subunit of the eukaryotic signal recognition particle...
  43. Suzuma S, Hayashi K, Nakamura K, Yamane K. Analysis of Escherichia coli 4.5S RNA binding affinity to Ffh and EF-G. FEMS Microbiol Lett. 1999;180:271-7 pubmed
    Escherichia coli 4.5S RNA is a member of the signal recognition particle RNA family that binds to Ffh and EF-G proteins in vivo. To assess the binding affinity of E. coli 4...
  44. Jensen C, Brown S, Pedersen S. Effect of 4.5S RNA depletion on Escherichia coli protein synthesis and secretion. J Bacteriol. 1994;176:2502-6 pubmed
    ..After further depletion of 4.5S RNA, accumulation of precursors of secreted proteins was observed under some growth conditions. ..
  45. Funes S, Westerburg H, Jaimes Miranda F, Woellhaf M, Aguilar Lopez J, Jansen L, et al. Partial suppression of Oxa1 mutants by mitochondria-targeted signal recognition particle provides insights into the evolution of the cotranslational insertion systems. FEBS J. 2013;280:904-15 pubmed publisher
    ..In this study, we expressed mitochondria-targeted versions of the bacterial SRP protein Ffh and its receptor FtsY in these yeast mutants...
  46. Poritz M, Bernstein H, Strub K, Zopf D, Wilhelm H, Walter P. An E. coli ribonucleoprotein containing 4.5S RNA resembles mammalian signal recognition particle. Science. 1990;250:1111-7 pubmed
    ..Sequence comparisons, however, have identified (i) a gene in Escherichia coli (ffh) whose product is homologous to the 54-kilodalton subunit (SRP54) of SRP, and (ii) an RNA encoded by the ffs gene (..
  47. March P. Membrane-associated GTPases in bacteria. Mol Microbiol. 1992;6:1253-7 pubmed
    ..The amino acid sequences of FtsY and Ffh are clearly related to eukaryotic factors involved in protein secretion...
  48. Miyazaki R, Yura T, Suzuki T, Dohmae N, Mori H, Akiyama Y. A Novel SRP Recognition Sequence in the Homeostatic Control Region of Heat Shock Transcription Factor ?32. Sci Rep. 2016;6:24147 pubmed publisher
    ..region of ?(32) that lacks a consecutive hydrophobic stretch interacts with the signal peptide-binding site of Ffh (the protein subunit of SRP)...
  49. Buskiewicz I, Peske F, Wieden H, Gryczynski I, Rodnina M, Wintermeyer W. Conformations of the signal recognition particle protein Ffh from Escherichia coli as determined by FRET. J Mol Biol. 2005;351:417-30 pubmed
    ..SRP in Escherichia coli is composed of one protein, Ffh, and 4.5S RNA. In the present work, we probe the structure of Ffh alone and in the complex with 4...
  50. von Loeffelholz O, Knoops K, Ariosa A, Zhang X, Karuppasamy M, Huard K, et al. Structural basis of signal sequence surveillance and selection by the SRP-FtsY complex. Nat Struct Mol Biol. 2013;20:604-10 pubmed publisher
    ..microscopy structure of this 'false' early complex with EspP revealed an ordered M domain of SRP protein Ffh making two ribosomal contacts, and the NG domains of Ffh and FtsY forming a distorted, flexible heterodimer...
  51. Persson B, Bylund G, Berg D, Wikström P. Functional analysis of the ffh-trmD region of the Escherichia coli chromosome by using reverse genetics. J Bacteriol. 1995;177:5554-60 pubmed
    ..of each of four genes in the Escherichia coli trmD operon (rpsP, 21K, trmD, and rplS) and of the flanking genes ffh and 16K by a reverse genetic method...
  52. Jagath J, Matassova N, De Leeuw E, Warnecke J, Lentzen G, Rodnina M, et al. Important role of the tetraloop region of 4.5S RNA in SRP binding to its receptor FtsY. RNA. 2001;7:293-301 pubmed
    ..by the structure of the tetraloop region of SRP RNA, in particular the tetraloop stem, and suggest that both SRP RNA and Ffh undergo mutual structural adaptation to form SRP that is functional in the interaction with the receptor, FtsY.
  53. Angelini S, Boy D, Schiltz E, Koch H. Membrane binding of the bacterial signal recognition particle receptor involves two distinct binding sites. J Cell Biol. 2006;174:715-24 pubmed
    ..This interaction is stabilized by the N-terminal A-domain of FtsY, which probably serves as a transient lipid anchor. ..
  54. Bradshaw N, Neher S, Booth D, Walter P. Signal sequences activate the catalytic switch of SRP RNA. Science. 2009;323:127-30 pubmed publisher
    ..Thus, SRP RNA is a molecular switch that renders the SRP-SR GTPase engine responsive to signal peptide recruitment, coupling GTP hydrolysis to productive protein targeting. ..
  55. Phillips G, Silhavy T. The E. coli ffh gene is necessary for viability and efficient protein export. Nature. 1992;359:744-6 pubmed
    ..The Escherichia coli homologue, termed ffh (for fifty-four homologue), specifies a protein (Ffh) that shares many properties with its eukaryotic counterpart, ..
  56. Andersen E, Rosenblad M, Larsen N, Westergaard J, Burks J, Wower I, et al. The tmRDB and SRPDB resources. Nucleic Acids Res. 2006;34:D163-8 pubmed publisher
    ..S1, alanyl-tRNA synthetase and Elongation Factor Tu, as well as the SRP proteins SRP9, SRP14, SRP19, SRP21, SRP54 (Ffh), SRP68, SRP72, cpSRP43, Flhf, SRP receptor (alpha) and SRP receptor (beta)...
  57. Maier K, Hubich S, Liebhart H, Krauss S, Kuhn A, Facey S. An amphiphilic region in the cytoplasmic domain of KdpD is recognized by the signal recognition particle and targeted to the Escherichia coli membrane. Mol Microbiol. 2008;68:1471-84 pubmed publisher
    ..This shows that membrane proteins with a large N-terminal region in the cytoplasm can be membrane-targeted early on to allow co-translational membrane insertion of their distant transmembrane regions. ..
  58. Chen S, Fan Y, Shen X, Sun P, Jiang G, Shen Y, et al. A molecular modeling study of the interaction between SRP-receptor complex and peptide translocon. Biochem Biophys Res Commun. 2008;377:346-350 pubmed publisher
    ..A structure model, showing how nascent peptide inserts into peptide translocon with the help of SRP protein Ffh and its receptor FtsY, is desired to facilitate our studies...
  59. Eisner G, Koch H, Beck K, Brunner J, Muller M. Ligand crowding at a nascent signal sequence. J Cell Biol. 2003;163:35-44 pubmed
    ..Immediately after emerging from the ribosome, the signal sequence of pOmpA is accessible to Ffh, the protein component of the bacterial signal recognition particle, and to SecA, but it remains attached to the ..
  60. Swain J, Gierasch L. Signal peptides bind and aggregate RNA. An alternative explanation for GTPase inhibition in the signal recognition particle. J Biol Chem. 2001;276:12222-7 pubmed
  61. Zhang X, Schaffitzel C, Ban N, Shan S. Multiple conformational switches in a GTPase complex control co-translational protein targeting. Proc Natl Acad Sci U S A. 2009;106:1754-9 pubmed publisher
    ..Thus, the SRP and SR GTPases, without recruiting external regulatory factors, constitute a self-sufficient system that provides exquisite spatial and temporal control of a complex cellular process. ..
  62. Braig D, Bär C, Thumfart J, Koch H. Two cooperating helices constitute the lipid-binding domain of the bacterial SRP receptor. J Mol Biol. 2009;390:401-13 pubmed publisher
    ..This explains why the bacterial SRP receptor does not require an integral beta-subunit for membrane binding. ..
  63. Sijbrandi R, Urbanus M, ten Hagen Jongman C, Bernstein H, Oudega B, Otto B, et al. Signal recognition particle (SRP)-mediated targeting and Sec-dependent translocation of an extracellular Escherichia coli protein. J Biol Chem. 2003;278:4654-9 pubmed publisher
    ..We propose that these autotransporters preferentially use the co-translational SRP/Sec route to avoid adverse effects of the exposure of their mature domains in the cytoplasm...
  64. Oh D, Yi G, Chi S, Kim H. Structure of a methionine-rich segment of Escherichia coli Ffh protein. FEBS Lett. 1996;395:160-4 pubmed
    The methionine-rich segments of the Ffh protein of Escherichia coli and its eukaryotic counterpart SRP54 are thought to bind signal sequences of secretory proteins...
  65. Ribes V, Römisch K, Giner A, Dobberstein B, Tollervey D. E. coli 4.5S RNA is part of a ribonucleoprotein particle that has properties related to signal recognition particle. Cell. 1990;63:591-600 pubmed
    ..Strains overproducing P48 also accumulate pre-beta-lactamase. 4.5S RNA and P48 are components of a ribonucleoprotein particle that we propose to be required for the secretion of some proteins. ..