No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.

EcoSal Plus

Domain 4:

Synthesis and Processing of Macromolecules

The Twin-Arginine Pathway for Protein Secretion

MyBook is a cheap paperback edition of the original book and will be sold at uniform, low price.
  • Authors: Kelly M. Frain1, Jan Maarten van Dijl2, and Colin Robinson3
  • Editors: Maria Sandkvist4, Eric Cascales5, Peter J. Christie6
    Affiliations: 1: The School of Biosciences, University of Kent, Canterbury CT2 7NZ, United Kingdom; 2: University of Groningen, University Medical Center Groningen, Department of Medical Microbiology, Groningen, The Netherlands; 3: The School of Biosciences, University of Kent, Canterbury CT2 7NZ, United Kingdom; 4: Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan; 5: CNRS Aix-Marseille Université, Mediterranean Institute of Microbiology, Marseille, France; 6: Department of Microbiology and Molecular Genetics, McGovern Medical School, Houston, Texas
  • Received 15 November 2018 Accepted 06 May 2019 Published 19 June 2019
  • Address correspondence to Jan Maarten van Dijl, [email protected]
image of The Twin-Arginine Pathway for Protein Secretion
    Preview this reference work article:
    Zoom in

    The Twin-Arginine Pathway for Protein Secretion, Page 1 of 2

    | /docserver/preview/fulltext/ecosalplus/8/2/ESP-0040-2018-1.gif /docserver/preview/fulltext/ecosalplus/8/2/ESP-0040-2018-2.gif
  • Abstract:

    The Tat pathway for protein translocation across bacterial membranes stands out for its selective handling of fully folded cargo proteins. In this review, we provide a comprehensive summary of our current understanding of the different known Tat components, their assembly into different complexes, and their specific roles in the protein translocation process. In particular, this overview focuses on the Gram-negative bacterium and the Gram-positive bacterium . Using these organisms as examples, we discuss structural features of Tat complexes alongside mechanistic models that allow for the Tat pathway’s unique protein proofreading and transport capabilities. Finally, we highlight recent advances in exploiting the Tat pathway for biotechnological benefit, the production of high-value pharmaceutical proteins.

  • Citation: Frain K, van Dijl J, Robinson C. 2019. The Twin-Arginine Pathway for Protein Secretion, EcoSal Plus 2019; doi:10.1128/ecosalplus.ESP-0040-2018

Article Version

This article is an updated version of the following content:


1. Holland IB. 2004. Translocation of bacterial proteins—an overview. Biochim Biophys Acta 1694:5–16. http://dx.doi.org/10.1016/j.bbamcr.2004.02.007. [PubMed]
2. Palmer T, Sargent F, Berks BC. 2010. The Tat protein export pathway. EcoSal Plus 4:4.3.2. http://dx.doi.org/10.1128/ecosalplus.4.3.2. [PubMed]
3. von Heijne G. 1990. The signal peptide. J Membr Biol 115:195–201. http://dx.doi.org/10.1007/BF01868635. [PubMed]
4. Lüke I, Handford JI, Palmer T, Sargent F. 2009. Proteolytic processing of Escherichia coli twin-arginine signal peptides by LepB. Arch Microbiol 191:919–925. http://dx.doi.org/10.1007/s00203-009-0516-5. [PubMed]
5. Jongbloed JDH, Grieger U, Antelmann H, Hecker M, Nijland R, Bron S, van Dijl JM. 2004. Two minimal Tat translocases in Bacillus. Mol Microbiol 54:1319–1325. http://dx.doi.org/10.1111/j.1365-2958.2004.04341.x. [PubMed]
6. Dalbey RE, Wang P, van Dijl JM. 2012. Membrane proteases in the bacterial protein secretion and quality control pathway. Microbiol Mol Biol Rev 76:311–330. http://dx.doi.org/10.1128/MMBR.05019-11. [PubMed]
7. Sakaguchi M, Tomiyoshi R, Kuroiwa T, Mihara K, Omura T. 1992. Functions of signal and signal-anchor sequences are determined by the balance between the hydrophobic segment and the N-terminal charge. Proc Natl Acad Sci U S A 89:16–19. http://dx.doi.org/10.1073/pnas.89.1.16. [PubMed]
8. Berks BC. 1996. A common export pathway for proteins binding complex redox cofactors? Mol Microbiol 22:393–404. http://dx.doi.org/10.1046/j.1365-2958.1996.00114.x. [PubMed]
9. Sargent F, Bogsch EG, Stanley NR, Wexler M, Robinson C, Berks BC, Palmer T. 1998. Overlapping functions of components of a bacterial Sec-independent protein export pathway. EMBO J 17:3640–3650. http://dx.doi.org/10.1093/emboj/17.13.3640. [PubMed]
10. Berks BC, Palmer T, Sargent F. 2003. The Tat protein translocation pathway and its role in microbial physiology. Adv Microb Physiol 47:187–254. http://dx.doi.org/10.1016/S0065-2911(03)47004-5.
11. Stanley NR, Palmer T, Berks BC. 2000. The twin arginine consensus motif of Tat signal peptides is involved in Sec-independent protein targeting in Escherichia coli. J Biol Chem 275:11591–11596. http://dx.doi.org/10.1074/jbc.275.16.11591. [PubMed]
12. Buchanan G, Sargent F, Berks BC, Palmer T. 2001. A genetic screen for suppressors of Escherichia coli Tat signal peptide mutations establishes a critical role for the second arginine within the twin-arginine motif. Arch Microbiol 177:107–112. http://dx.doi.org/10.1007/s00203-001-0366-2. [PubMed]
13. Chaddock AM, Mant A, Karnauchov I, Brink S, Herrmann RG, Klösgen RB, Robinson C. 1995. A new type of signal peptide: central role of a twin-arginine motif in transfer signals for the delta pH-dependent thylakoidal protein translocase. EMBO J 14:2715–2722. http://dx.doi.org/10.1002/j.1460-2075.1995.tb07272.x. [PubMed]
14. Halbig D, Hou B, Freudl R, Sprenger GA, Klösgen RB. 1999. Bacterial proteins carrying twin-R signal peptides are specifically targeted by the delta pH-dependent transport machinery of the thylakoid membrane system. FEBS Lett 447:95–98. http://dx.doi.org/10.1016/S0014-5793(99)00269-0.
15. Hinsley AP, Stanley NR, Palmer T, Berks BC. 2001. A naturally occurring bacterial Tat signal peptide lacking one of the ‘invariant’ arginine residues of the consensus targeting motif. FEBS Lett 497:45–49. http://dx.doi.org/10.1016/S0014-5793(01)02428-0.
16. DeLisa MP, Samuelson P, Palmer T, Georgiou G. 2002. Genetic analysis of the twin arginine translocator secretion pathway in bacteria. J Biol Chem 277:29825–29831. http://dx.doi.org/10.1074/jbc.M201956200. [PubMed]
17. Tullman-Ercek D, DeLisa MP, Kawarasaki Y, Iranpour P, Ribnicky B, Palmer T, Georgiou G. 2007. Export pathway selectivity of Escherichia coli twin arginine translocation signal peptides. J Biol Chem 282:8309–8316. http://dx.doi.org/10.1074/jbc.M610507200. [PubMed]
18. Cristóbal S, de Gier JW, Nielsen H, von Heijne G. 1999. Competition between Sec- and TAT-dependent protein translocation in Escherichia coli. EMBO J 18:2982–2990. http://dx.doi.org/10.1093/emboj/18.11.2982. [PubMed]
19. Bogsch E, Brink S, Robinson C. 1997. Pathway specificity for a delta pH-dependent precursor thylakoid lumen protein is governed by a ‘Sec-avoidance’ motif in the transfer peptide and a ‘Sec-incompatible’ mature protein. EMBO J 16:3851–3859. http://dx.doi.org/10.1093/emboj/16.13.3851. [PubMed]
20. Mould RM, Robinson C. 1991. A proton gradient is required for the transport of two lumenal oxygen-evolving proteins across the thylakoid membrane. J Biol Chem 266:12189–12193.
21. Klösgen RB, Brock IW, Herrmann RG, Robinson C. 1992. Proton gradient-driven import of the 16 kDa oxygen-evolving complex protein as the full precursor protein by isolated thylakoids. Plant Mol Biol 18:1031–1034. http://dx.doi.org/10.1007/BF00019226. [PubMed]
22. Clark SA, Theg SM. 1997. A folded protein can be transported across the chloroplast envelope and thylakoid membranes. Mol Biol Cell 8:923–934. http://dx.doi.org/10.1091/mbc.8.5.923. [PubMed]
23. Mori H, Summer EJ, Ma X, Cline K. 1999. Component specificity for the thylakoidal Sec and ΔpH-dependent protein transport pathways. J Cell Biol 146:45–56. http://dx.doi.org/10.1083/jcb.146.1.45. [PubMed]
24. Settles AM, Yonetani A, Baron A, Bush DR, Cline K, Martienssen R. 1997. Sec-independent protein translocation by the maize Hcf106 protein. Science 278:1467–1470. http://dx.doi.org/10.1126/science.278.5342.1467. [PubMed]
25. Cline K, Mori H. 2001. Thylakoid DeltapH-dependent precursor proteins bind to a cpTatC-Hcf106 complex before Tha4-dependent transport. J Cell Biol 154:719–729. http://dx.doi.org/10.1083/jcb.200105149. [PubMed]
26. Wu LF, Ize B, Chanal A, Quentin Y, Fichant G. 2000. Bacterial twin-arginine signal peptide-dependent protein translocation pathway: evolution and mechanism. J Mol Microbiol Biotechnol 2:179–189.
27. Bogsch EG, Sargent F, Stanley NR, Berks BC, Robinson C, Palmer T. 1998. An essential component of a novel bacterial protein export system with homologues in plastids and mitochondria. J Biol Chem 273:18003–18006. http://dx.doi.org/10.1074/jbc.273.29.18003. [PubMed]
28. Sargent F, Stanley NR, Berks BC, Palmer T. 1999. Sec-independent protein translocation in Escherichia coli. A distinct and pivotal role for the TatB protein. J Biol Chem 274:36073–36082. http://dx.doi.org/10.1074/jbc.274.51.36073. [PubMed]
29. Palmer T, Sargent F, Berks BC. 2005. Export of complex cofactor-containing proteins by the bacterial Tat pathway. Trends Microbiol 13:175–180. http://dx.doi.org/10.1016/j.tim.2005.02.002. [PubMed]
30. Rodrigue A, Chanal A, Beck K, Müller M, Wu LF. 1999. Co-translocation of a periplasmic enzyme complex by a hitchhiker mechanism through the bacterial Tat pathway. J Biol Chem 274:13223–13228. http://dx.doi.org/10.1074/jbc.274.19.13223. [PubMed]
31. Bernhardt TG, de Boer PAJ. 2003. The Escherichia coli amidase AmiC is a periplasmic septal ring component exported via the twin-arginine transport pathway. Mol Microbiol 48:1171–1182. http://dx.doi.org/10.1046/j.1365-2958.2003.03511.x.
32. Ize B, Stanley NR, Buchanan G, Palmer T. 2003. Role of the Escherichia coli Tat pathway in outer membrane integrity. Mol Microbiol 48:1183–1193. http://dx.doi.org/10.1046/j.1365-2958.2003.03504.x. [PubMed]
33. Ding Z, Christie PJ. 2003. Agrobacterium tumefaciens twin-arginine-dependent translocation is important for virulence, flagellation, and chemotaxis but not type IV secretion. J Bacteriol 185:760–771. http://dx.doi.org/10.1128/JB.185.3.760-771.2003. [PubMed]
34. Craig M, Sadik AY, Golubeva YA, Tidhar A, Slauch JM. 2013. Twin-arginine translocation system ( tat) mutants of Salmonella are attenuated due to envelope defects, not respiratory defects. Mol Microbiol 89:887–902. http://dx.doi.org/10.1111/mmi.12318. [PubMed]
35. Hynds PJ, Robinson D, Robinson C. 1998. The Sec-independent twin-arginine translocation system can transport both tightly folded and malfolded proteins across the thylakoid membrane. J Biol Chem 273:34868–34874. http://dx.doi.org/10.1074/jbc.273.52.34868. [PubMed]
36. Santini CL, Bernadac A, Zhang M, Chanal A, Ize B, Blanco C, Wu LF. 2001. Translocation of jellyfish green fluorescent protein via the Tat system of Escherichia coli and change of its periplasmic localization in response to osmotic up-shock. J Biol Chem 276:8159–8164. http://dx.doi.org/10.1074/jbc.C000833200. [PubMed]
37. Alanen HI, Walker KL, Lourdes Velez Suberbie M, Matos CFRO, Bönisch S, Freedman RB, Keshavarz-Moore E, Ruddock LW, Robinson C. 2015. Efficient export of human growth hormone, interferon α2b and antibody fragments to the periplasm by the Escherichia coli Tat pathway in the absence of prior disulfide bond formation. Biochim Biophys Acta 1853:756–763. http://dx.doi.org/10.1016/j.bbamcr.2014.12.027. [PubMed]
38. DeLisa MP, Tullman D, Georgiou G. 2003. Folding quality control in the export of proteins by the bacterial twin-arginine translocation pathway. Proc Natl Acad Sci U S A 100:6115–6120. http://dx.doi.org/10.1073/pnas.0937838100. [PubMed]
39. Richter S, Brüser T. 2005. Targeting of unfolded PhoA to the TAT translocon of Escherichia coli. J Biol Chem 280:42723–42730. http://dx.doi.org/10.1074/jbc.M509570200. [PubMed]
40. Jack RL, Sargent F, Berks BC, Sawers G, Palmer T. 2001. Constitutive expression of Escherichia colitat genes indicates an important role for the twin-arginine translocase during aerobic and anaerobic growth. J Bacteriol 183:1801–1804. http://dx.doi.org/10.1128/JB.183.5.1801-1804.2001. [PubMed]
41. Baglieri J, Beck D, Vasisht N, Smith CJ, Robinson C. 2012. Structure of TatA paralog, TatE, suggests a structurally homogeneous form of Tat protein translocase that transports folded proteins of differing diameter. J Biol Chem 287:7335–7344. http://dx.doi.org/10.1074/jbc.M111.326355. [PubMed]
42. Stanley NR, Findlay K, Berks BC, Palmer T. 2001. Escherichia coli strains blocked in Tat-dependent protein export exhibit pleiotropic defects in the cell envelope. J Bacteriol 183:139–144. http://dx.doi.org/10.1128/JB.183.1.139-144.2001. [PubMed]
43. Goosens VJ, Monteferrante CG, van Dijl JM. 2014. The Tat system of Gram-positive bacteria. Biochim Biophys Acta 1843:1698–1706. http://dx.doi.org/10.1016/j.bbamcr.2013.10.008. [PubMed]
44. Ridder AN, de Jong EJ, Jongbloed JD, Kuipers OP, van Dijl JM, Robinson C, Smith C. 2009. Subcellular localization of TatAd of Bacillus subtilis depends on the presence of TatCd or TatCy. J Bacteriol 191:4410–4418. http://dx.doi.org/10.1128/JB.00215-09. [PubMed]
45. Jongbloed JDH, Martin U, Antelmann H, Hecker M, Tjalsma H, Venema G, Bron S, van Dijl JM, Müller J. 2000. TatC is a specificity determinant for protein secretion via the twin-arginine translocation pathway. J Biol Chem 275:41350–41357. http://dx.doi.org/10.1074/jbc.M004887200. [PubMed]
46. van der Ploeg R, Mäder U, Homuth G, Schaffer M, Denham EL, Monteferrante CG, Miethke M, Marahiel MA, Harwood CR, Winter T, Hecker M, Antelmann H, van Dijl JM. 2011. Environmental salinity determines the specificity and need for Tat-dependent secretion of the YwbN protein in Bacillus subtilis. PLoS One 6:e18140. http://dx.doi.org/10.1371/journal.pone.0018140. [PubMed]
47. Monteferrante CG, Miethke M, van der Ploeg R, Glasner C, van Dijl JM. 2012. Specific targeting of the metallophosphoesterase YkuE to the Bacillus cell wall requires the twin-arginine translocation system. J Biol Chem 287:29789–29800. http://dx.doi.org/10.1074/jbc.M112.378190. [PubMed]
48. Miethke M, Monteferrante CG, Marahiel MA, van Dijl JM. 2013. The Bacillus subtilis EfeUOB transporter is essential for high-affinity acquisition of ferrous and ferric iron. Biochim Biophys Acta 1833:2267–2278. http://dx.doi.org/10.1016/j.bbamcr.2013.05.027. [PubMed]
49. Goosens VJ, Otto A, Glasner C, Monteferrante CC, van der Ploeg R, Hecker M, Becher D, van Dijl JM. 2013. Novel twin-arginine translocation pathway-dependent phenotypes of Bacillus subtilis unveiled by quantitative proteomics. J Proteome Res 12:796–807. http://dx.doi.org/10.1021/pr300866f. [PubMed]
50. Goosens VJ, De-San-Eustaquio-Campillo A, Carballido-López R, van Dijl JM. 2015. A Tat ménage à trois—the role of Bacillus subtilis TatAc in twin-arginine protein translocation. Biochim Biophys Acta 1853(10 Part A) :2745–2753. http://dx.doi.org/10.1016/j.bbamcr.2015.07.022. [PubMed]
51. Sargent F, Gohlke U, De Leeuw E, Stanley NR, Palmer T, Saibil HR, Berks BC. 2001. Purified components of the Escherichia coli Tat protein transport system form a double-layered ring structure. Eur J Biochem 268:3361–3367. http://dx.doi.org/10.1046/j.1432-1327.2001.02263.x. [PubMed]
52. Barnett JP, Eijlander RT, Kuipers OP, Robinson C. 2008. A minimal Tat system from a gram-positive organism: a bifunctional TatA subunit participates in discrete TatAC and TatA complexes. J Biol Chem 283:2534–2542. http://dx.doi.org/10.1074/jbc.M708134200. [PubMed]
53. Monteferrante CG, Baglieri J, Robinson C, van Dijl JM. 2012. TatAc, the third TatA subunit of Bacillus subtilis, can form active twin-arginine translocases with the TatCd and TatCy subunits. Appl Environ Microbiol 78:4999–5001. http://dx.doi.org/10.1128/AEM.01108-12. [PubMed]
54. Beck D, Vasisht N, Baglieri J, Monteferrante CG, van Dijl JM, Robinson C, Smith CJ. 2013. Ultrastructural characterisation of Bacillus subtilis TatA complexes suggests they are too small to form homooligomeric translocation pores. Biochim Biophys Acta 1833:1811–1819. http://dx.doi.org/10.1016/j.bbamcr.2013.03.028. [PubMed]
55. Porcelli I, de Leeuw E, Wallis R, van den Brink-van der Laan E, de Kruijff B, Wallace BA, Palmer T, Berks BC. 2002. Characterization and membrane assembly of the TatA component of the Escherichia coli twin-arginine protein transport system. Biochemistry 41:13690–13697. http://dx.doi.org/10.1021/bi026142i. [PubMed]
56. Koch S, Fritsch MJ, Buchanan G, Palmer T. 2012. Escherichia coli TatA and TatB proteins have N-out, C-in topology in intact cells. J Biol Chem 287:14420–14431. http://dx.doi.org/10.1074/jbc.M112.354555. [PubMed]
57. Hu Y, Zhao E, Li H, Xia B, Jin C. 2010. Solution NMR structure of the TatA component of the twin-arginine protein transport system from gram-positive bacterium Bacillus subtilis. J Am Chem Soc 132:15942–15944. http://dx.doi.org/10.1021/ja1053785. [PubMed]
58. Rodriguez F, Rouse SL, Tait CE, Harmer J, De Riso A, Timmel CR, Sansom MS, Berks BC, Schnell JR. 2013. Structural model for the protein-translocating element of the twin-arginine transport system. Proc Natl Acad Sci U S A 110:E1092–E1101. http://dx.doi.org/10.1073/pnas.1219486110. [PubMed]
59. Müller SD, De Angelis AA, Walther TH, Grage SL, Lange C, Opella SJ, Ulrich AS. 2007. Structural characterization of the pore forming protein TatAd of the twin-arginine translocase in membranes by solid-state 15N-NMR. Biochim Biophys Acta 1768:3071–3079. http://dx.doi.org/10.1016/j.bbamem.2007.09.008. [PubMed]
60. Walther TH, Grage SL, Roth N, Ulrich AS. 2010. Membrane alignment of the pore-forming component TatA(d) of the twin-arginine translocase from Bacillus subtilis resolved by solid-state NMR spectroscopy. J Am Chem Soc 132:15945–15956. http://dx.doi.org/10.1021/ja106963s. [PubMed]
61. Lange C, Müller SD, Walther TH, Bürck J, Ulrich AS. 2007. Structure analysis of the protein translocating channel TatA in membranes using a multi-construct approach. Biochim Biophys Acta 1768:2627–2634. http://dx.doi.org/10.1016/j.bbamem.2007.06.021. [PubMed]
62. Barrett CML, Ray N, Thomas JD, Robinson C, Bolhuis A. 2003. Quantitative export of a reporter protein, GFP, by the twin-arginine translocation pathway in Escherichia coli. Biochem Biophys Res Commun 304:279–284. http://dx.doi.org/10.1016/S0006-291X(03)00583-7.
63. Hicks MG, de Leeuw E, Porcelli I, Buchanan G, Berks BC, Palmer T. 2003. The Escherichia coli twin-arginine translocase: conserved residues of TatA and TatB family components involved in protein transport. FEBS Lett 539:61–67. http://dx.doi.org/10.1016/S0014-5793(03)00198-4.
64. Greene NP, Porcelli I, Buchanan G, Hicks MG, Schermann SM, Palmer T, Berks BC. 2007. Cysteine scanning mutagenesis and disulfide mapping studies of the TatA component of the bacterial twin arginine translocase. J Biol Chem 282:23937–23945. http://dx.doi.org/10.1074/jbc.M702972200. [PubMed]
65. Eimer E, Fröbel J, Blümmel AS, Müller M. 2015. TatE as a regular constituent of bacterial twin-arginine protein translocases. J Biol Chem 290:29281–29289. http://dx.doi.org/10.1074/jbc.M115.696005. [PubMed]
66. Eimer E, Kao WC, Fröbel J, Blümmel AS, Hunte C, Müller M. 2018. Unanticipated functional diversity among the TatA-type components of the Tat protein translocase. Sci Rep 8:1326. http://dx.doi.org/10.1038/s41598-018-19640-3. [PubMed]
67. Zhang Y, Wang L, Hu Y, Jin C. 2014. Solution structure of the TatB component of the twin-arginine translocation system. Biochim Biophys Acta 1838:1881–1888. http://dx.doi.org/10.1016/j.bbamem.2014.03.015. [PubMed]
68. Lee PA, Buchanan G, Stanley NR, Berks BC, Palmer T. 2002. Truncation analysis of TatA and TatB defines the minimal functional units required for protein translocation. J Bacteriol 184:5871–5879. http://dx.doi.org/10.1128/JB.184.21.5871-5879.2002. [PubMed]
69. Barrett CML, Mathers JE, Robinson C. 2003. Identification of key regions within the Escherichia coli TatAB subunits. FEBS Lett 537:42–46. http://dx.doi.org/10.1016/S0014-5793(03)00068-1.
70. Blaudeck N, Kreutzenbeck P, Müller M, Sprenger GA, Freudl R. 2005. Isolation and characterization of bifunctional Escherichia coli TatA mutant proteins that allow efficient Tat-dependent protein translocation in the absence of TatB. J Biol Chem 280:3426–3432. http://dx.doi.org/10.1074/jbc.M411210200. [PubMed]
71. Barrett CML, Freudl R, Robinson C. 2007. Twin arginine translocation (Tat)-dependent export in the apparent absence of TatABC or TatA complexes using modified Escherichia coli TatA subunits that substitute for TatB. J Biol Chem 282:36206–36213. http://dx.doi.org/10.1074/jbc.M704127200. [PubMed]
72. Jongbloed JDH, van der Ploeg R, van Dijl JM. 2006. Bifunctional TatA subunits in minimal Tat protein translocases. Trends Microbiol 14:2–4. http://dx.doi.org/10.1016/j.tim.2005.11.001. [PubMed]
73. Tarry MJ, Schäfer E, Chen S, Buchanan G, Greene NP, Lea SM, Palmer T, Saibil HR, Berks BC. 2009. Structural analysis of substrate binding by the TatBC component of the twin-arginine protein transport system. Proc Natl Acad Sci U S A 106:13284–13289. http://dx.doi.org/10.1073/pnas.0901566106. [PubMed]
74. Kneuper H, Maldonado B, Jäger F, Krehenbrink M, Buchanan G, Keller R, Müller M, Berks BC, Palmer T. 2012. Molecular dissection of TatC defines critical regions essential for protein transport and a TatB-TatC contact site. Mol Microbiol 85:945–961. http://dx.doi.org/10.1111/j.1365-2958.2012.08151.x. [PubMed]
75. Behrendt J, Standar K, Lindenstrauss U, Brüser T. 2004. Topological studies on the twin-arginine translocase component TatC. FEMS Microbiol Lett 234:303–308. http://dx.doi.org/10.1111/j.1574-6968.2004.tb09548.x. [PubMed]
76. Ramasamy S, Abrol R, Suloway CJM, Clemons WM, Jr. 2013. The glove-like structure of the conserved membrane protein TatC provides insight into signal sequence recognition in twin-arginine translocation. Structure 21:777–788. http://dx.doi.org/10.1016/j.str.2013.03.004. [PubMed]
77. Rollauer SE, Tarry MJ, Graham JE, Jääskeläinen M, Jäger F, Johnson S, Krehenbrink M, Liu SM, Lukey MJ, Marcoux J, McDowell MA, Rodriguez F, Roversi P, Stansfeld PJ, Robinson CV, Sansom MS, Palmer T, Högbom M, Berks BC, Lea SM. 2012. Structure of the TatC core of the twin-arginine protein transport system. Nature 492:210–214. http://dx.doi.org/10.1038/nature11683. [PubMed]
78. Blümmel AS, Drepper F, Knapp B, Eimer E, Warscheid B, Müller M, Fröbel J. 2017. Structural features of the TatC membrane protein that determine docking and insertion of a twin-arginine signal peptide. J Biol Chem 292:21320–21329. http://dx.doi.org/10.1074/jbc.M117.812560. [PubMed]
79. Holzapfel E, Eisner G, Alami M, Barrett CML, Buchanan G, Lüke I, Betton JM, Robinson C, Palmer T, Moser M, Müller M. 2007. The entire N-terminal half of TatC is involved in twin-arginine precursor binding. Biochemistry 46:2892–2898. http://dx.doi.org/10.1021/bi062205b. [PubMed]
80. Schaerlaekens K, Schierová M, Lammertyn E, Geukens N, Anné J, Van Mellaert L. 2001. Twin-arginine translocation pathway in Streptomyces lividans. J Bacteriol 183:6727–6732. http://dx.doi.org/10.1128/JB.183.23.6727-6732.2001. [PubMed]
81. Barnett JP, Lawrence J, Mendel S, Robinson C. 2011. Expression of the bifunctional Bacillus subtilis TatAd protein in Escherichia coli reveals distinct TatA/B-family and TatB-specific domains. Arch Microbiol 193:583–594. http://dx.doi.org/10.1007/s00203-011-0699-4. [PubMed]
82. Schreiber S, Stengel R, Westermann M, Volkmer-Engert R, Pop OI, Müller JP. 2006. Affinity of TatCd for TatAd elucidates its receptor function in the Bacillus subtilis twin arginine translocation (Tat) translocase system. J Biol Chem 281:19977–19984. http://dx.doi.org/10.1074/jbc.M513900200. [PubMed]
83. Nolandt OV, Walther TH, Roth S, Bürck J, Ulrich AS. 2009. Structure analysis of the membrane protein TatC(d) from the Tat system of B. subtilis by circular dichroism. Biochim Biophys Acta 1788:2238–2244. http://dx.doi.org/10.1016/j.bbamem.2009.07.003. [PubMed]
84. van der Ploeg R, Barnett JP, Vasisht N, Goosens VJ, Pöther DC, Robinson C, van Dijl JM. 2011. Salt sensitivity of minimal twin arginine translocases. J Biol Chem 286:43759–43770. http://dx.doi.org/10.1074/jbc.M111.243824. [PubMed]
85. Patel R, Vasilev C, Beck D, Monteferrante CG, van Dijl JM, Hunter CN, Smith C, Robinson C. 2014. A mutation leading to super-assembly of twin-arginine translocase (Tat) protein complexes. Biochim Biophys Acta 1843:1978–1986. http://dx.doi.org/10.1016/j.bbamcr.2014.05.009. [PubMed]
86. Eijlander RT, Jongbloed JDH, Kuipers OP. 2009. Relaxed specificity of the Bacillus subtilis TatAdCd translocase in Tat-dependent protein secretion. J Bacteriol 191:196–202. http://dx.doi.org/10.1128/JB.01264-08. [PubMed]
87. Eijlander RT, Kolbusz MA, Berendsen EM, Kuipers OP. 2009. Effects of altered TatC proteins on protein secretion efficiency via the twin-arginine translocation pathway of Bacillus subtilis. Microbiology 155:1776–1785. http://dx.doi.org/10.1099/mic.0.027987-0. [PubMed]
88. Berks BC, Sargent F, Palmer T. 2000. The Tat protein export pathway. Mol Microbiol 35:260–274. http://dx.doi.org/10.1046/j.1365-2958.2000.01719.x. [PubMed]
89. Rose P, Fröbel J, Graumann PL, Müller M. 2013. Substrate-dependent assembly of the Tat translocase as observed in live Escherichia coli cells. PLoS One 8:e69488. http://dx.doi.org/10.1371/journal.pone.0069488. [PubMed]
90. Berks BC, Lea SM, Stansfeld PJ. 2014. Structural biology of Tat protein transport. Curr Opin Struct Biol 27:32–37. http://dx.doi.org/10.1016/j.sbi.2014.03.003. [PubMed]
91. Alami M, Lüke I, Deitermann S, Eisner G, Koch HG, Brunner J, Müller M. 2003. Differential interactions between a twin-arginine signal peptide and its translocase in Escherichia coli. Mol Cell 12:937–946. http://dx.doi.org/10.1016/S1097-2765(03)00398-8.
92. Celedon JM, Cline K. 2012. Stoichiometry for binding and transport by the twin arginine translocation system. J Cell Biol 197:523–534. http://dx.doi.org/10.1083/jcb.201201096. [PubMed]
93. Alcock F, Baker MAB, Greene NP, Palmer T, Wallace MI, Berks BC. 2013. Live cell imaging shows reversible assembly of the TatA component of the twin-arginine protein transport system. Proc Natl Acad Sci U S A 110:E3650–E3659. http://dx.doi.org/10.1073/pnas.1306738110. [PubMed]
94. Bolhuis A, Mathers JE, Thomas JD, Barrett CM, Robinson C, Robinson C. 2001. TatB and TatC form a functional and structural unit of the twin-arginine translocase from Escherichia coli. J Biol Chem 276:20213–20219. http://dx.doi.org/10.1074/jbc.M100682200. [PubMed]
95. Behrendt J, Brüser T. 2014. The TatBC complex of the Tat protein translocase in Escherichia coli and its transition to the substrate-bound TatABC complex. Biochemistry 53:2344–2354. http://dx.doi.org/10.1021/bi500169s. [PubMed]
96. Ma X, Cline K. 2010. Multiple precursor proteins bind individual Tat receptor complexes and are collectively transported. EMBO J 29:1477–1488. http://dx.doi.org/10.1038/emboj.2010.44. [PubMed]
97. Gérard F, Cline K. 2006. Efficient twin arginine translocation (Tat) pathway transport of a precursor protein covalently anchored to its initial cpTatC binding site. J Biol Chem 281:6130–6135. http://dx.doi.org/10.1074/jbc.M512733200. [PubMed]
98. Kreutzenbeck P, Kröger C, Lausberg F, Blaudeck N, Sprenger GA, Freudl R. 2007. Escherichia coli twin arginine (Tat) mutant translocases possessing relaxed signal peptide recognition specificities. J Biol Chem 282:7903–7911. http://dx.doi.org/10.1074/jbc.M610126200. [PubMed]
99. Zoufaly S, Fröbel J, Rose P, Flecken T, Maurer C, Moser M, Müller M. 2012. Mapping precursor-binding site on TatC subunit of twin arginine-specific protein translocase by site-specific photo cross-linking. J Biol Chem 287:13430–13441. http://dx.doi.org/10.1074/jbc.M112.343798. [PubMed]
100. Fröbel J, Rose P, Lausberg F, Blümmel A-S, Freudl R, Müller M. 2012. Transmembrane insertion of twin-arginine signal peptides is driven by TatC and regulated by TatB. Nat Commun 3:1311. http://dx.doi.org/10.1038/ncomms2308. [PubMed]
101. Blümmel AS, Haag LA, Eimer E, Müller M, Fröbel J. 2015. Initial assembly steps of a translocase for folded proteins. Nat Commun 6:7234. http://dx.doi.org/10.1038/ncomms8234. [PubMed]
102. Maurer C, Panahandeh S, Jungkamp A-C, Moser M, Müller M. 2010. TatB functions as an oligomeric binding site for folded Tat precursor proteins. Mol Biol Cell 21:4151–4161. http://dx.doi.org/10.1091/mbc.e10-07-0585. [PubMed]
103. Lee PA, Orriss GL, Buchanan G, Greene NP, Bond PJ, Punginelli C, Jack RL, Sansom MSP, Berks BC, Palmer T. 2006. Cysteine-scanning mutagenesis and disulfide mapping studies of the conserved domain of the twin-arginine translocase TatB component. J Biol Chem 281:34072–34085. http://dx.doi.org/10.1074/jbc.M607295200. [PubMed]
104. Cline K. 2015. Mechanistic aspects of folded protein transport by the twin arginine translocase (Tat). J Biol Chem 290:16530–16538. http://dx.doi.org/10.1074/jbc.R114.626820. [PubMed]
105. Alcock F, Stansfeld PJ, Basit H, Habersetzer J, Baker MA, Palmer T, Wallace MI, Berks BC. 2016. Assembling the Tat protein translocase. eLife 5:e20718. http://dx.doi.org/10.7554/eLife.20718. [PubMed]
106. Habersetzer J, Moore K, Cherry J, Buchanan G, Stansfeld PJ, Palmer T. 2017. Substrate-triggered position switching of TatA and TatB during Tat transport in Escherichia coli. Open Biol 7:8. http://dx.doi.org/10.1098/rsob.170091. [PubMed]
107. Gohlke U, Pullan L, McDevitt CA, Porcelli I, de Leeuw E, Palmer T, Saibil HR, Berks BC. 2005. The TatA component of the twin-arginine protein transport system forms channel complexes of variable diameter. Proc Natl Acad Sci U S A 102:10482–10486. http://dx.doi.org/10.1073/pnas.0503558102. [PubMed]
108. Brüser T, Sanders C. 2003. An alternative model of the twin arginine translocation system. Microbiol Res 158:7–17. http://dx.doi.org/10.1078/0944-5013-00176. [PubMed]
109. Orriss GL, Tarry MJ, Ize B, Sargent F, Lea SM, Palmer T, Berks BC. 2007. TatBC, TatB, and TatC form structurally autonomous units within the twin arginine protein transport system of Escherichia coli. FEBS Lett 581:4091–4097. http://dx.doi.org/10.1016/j.febslet.2007.07.044. [PubMed]
110. Aldridge C, Ma X, Gerard F, Cline K. 2014. Substrate-gated docking of pore subunit Tha4 in the TatC cavity initiates Tat translocase assembly. J Cell Biol 205:51–65. http://dx.doi.org/10.1083/jcb.201311057. [PubMed]
111. Hauer RS, Schlesier R, Heilmann K, Dittmar J, Jakob M, Klösgen RB. 2013. Enough is enough: TatA demand during Tat-dependent protein transport. Biochim Biophys Acta 1833:957–965. http://dx.doi.org/10.1016/j.bbamcr.2013.01.030. [PubMed]
112. Oates J, Barrett CML, Barnett JP, Byrne KG, Bolhuis A, Robinson C. 2005. The Escherichia coli twin-arginine translocation apparatus incorporates a distinct form of TatABC complex, spectrum of modular TatA complexes and minor TatAB complex. J Mol Biol 346:295–305. http://dx.doi.org/10.1016/j.jmb.2004.11.047. [PubMed]
113. White GF, Schermann SM, Bradley J, Roberts A, Greene NP, Berks BC, Thomson AJ. 2010. Subunit organization in the TatA complex of the twin arginine protein translocase: a site-directed EPR spin labeling study. J Biol Chem 285:2294–2301. http://dx.doi.org/10.1074/jbc.M109.065458. [PubMed]
114. Hou B, Heidrich ES, Mehner-Breitfeld D, Brüser T. 2018. The TatA component of the twin-arginine translocation system locally weakens the cytoplasmic membrane of Escherichia coli upon protein substrate binding. J Biol Chem 293:7592–7605. http://dx.doi.org/10.1074/jbc.RA118.002205. [PubMed]
115. Sargent F, Berks BC, Palmer T. 2006. Pathfinders and trailblazers: a prokaryotic targeting system for transport of folded proteins. FEMS Microbiol Lett 254:198–207. http://dx.doi.org/10.1111/j.1574-6968.2005.00049.x. [PubMed]
116. Gouffi K, Gérard F, Santini CL, Wu LF. 2004. Dual topology of the Escherichia coli TatA protein. J Biol Chem 279:11608–11615. http://dx.doi.org/10.1074/jbc.M313187200. [PubMed]
117. Walther TH, Gottselig C, Grage SL, Wolf M, Vargiu AV, Klein MJ, Vollmer S, Prock S, Hartmann M, Afonin S, Stockwald E, Heinzmann H, Nolandt OV, Wenzel W, Ruggerone P, Ulrich AS. 2013. Folding and self-assembly of the TatA translocation pore based on a charge zipper mechanism. Cell 152:316–326. http://dx.doi.org/10.1016/j.cell.2012.12.017. [PubMed]
118. Dabney-Smith C, Mori H, Cline K. 2006. Oligomers of Tha4 organize at the thylakoid Tat translocase during protein transport. J Biol Chem 281:5476–5483. http://dx.doi.org/10.1074/jbc.M512453200. [PubMed]
119. Chan CS, Zlomislic MR, Tieleman DP, Turner RJ. 2007. The TatA subunit of Escherichia coli twin-arginine translocase has an N-in topology. Biochemistry 46:7396–7404. http://dx.doi.org/10.1021/bi7005288. [PubMed]
120. Aldridge C, Storm A, Cline K, Dabney-Smith C. 2012. The chloroplast twin arginine transport (Tat) component, Tha4, undergoes conformational changes leading to Tat protein transport. J Biol Chem 287:34752–34763. http://dx.doi.org/10.1074/jbc.M112.385666. [PubMed]
121. Taubert J, Hou B, Risselada HJ, Mehner D, Lünsdorf H, Grubmüller H, Brüser T. 2015. TatBC-independent TatA/Tat substrate interactions contribute to transport efficiency. PLoS One 10:e0119761. http://dx.doi.org/10.1371/journal.pone.0119761. [PubMed]
122. Pal D, Fite K, Dabney-Smith C. 2013. Direct interaction between a precursor mature domain and transport component Tha4 during twin arginine transport of chloroplasts. Plant Physiol 161:990–1001. http://dx.doi.org/10.1104/pp.112.207522. [PubMed]
123. Taubert J, Brüser T. 2014. Twin-arginine translocation-arresting protein regions contact TatA and TatB. Biol Chem 395:827–836. http://dx.doi.org/10.1515/hsz-2014-0170. [PubMed]
124. Mould RM, Shackleton JB, Robinson C. 1991. Transport of proteins into chloroplasts. Requirements for the efficient import of two lumenal oxygen-evolving complex proteins into isolated thylakoids. J Biol Chem 266:17286–17289.
125. Mori H, Cline K. 2002. A twin arginine signal peptide and the pH gradient trigger reversible assembly of the thylakoid [Δ]pH/Tat translocase. J Cell Biol 157:205–210. http://dx.doi.org/10.1083/jcb.200202048. [PubMed]
126. DeLisa MP, Lee P, Palmer T, Georgiou G. 2004. Phage shock protein PspA of Escherichia coli relieves saturation of protein export via the Tat pathway. J Bacteriol 186:366–373. http://dx.doi.org/10.1128/JB.186.2.366-373.2004. [PubMed]
127. Finazzi G, Chasen C, Wollman FA, de Vitry C. 2003. Thylakoid targeting of Tat passenger proteins shows no delta pH dependence in vivo. EMBO J 22:807–815. http://dx.doi.org/10.1093/emboj/cdg081. [PubMed]
128. Braun NA, Davis AW, Theg SM. 2007. The chloroplast Tat pathway utilizes the transmembrane electric potential as an energy source. Biophys J 93:1993–1998. http://dx.doi.org/10.1529/biophysj.106.098731. [PubMed]
129. Musser SM, Theg SM. 2000. Proton transfer limits protein translocation rate by the thylakoid DeltapH/Tat machinery. Biochemistry 39:8228–8233. http://dx.doi.org/10.1021/bi000115f. [PubMed]
130. Alder NN, Theg SM. 2003. Energetics of protein transport across biological membranes. A study of the thylakoid DeltapH-dependent/cpTat pathway. Cell 112:231–242. http://dx.doi.org/10.1016/S0092-8674(03)00032-1.
131. Gérard F, Cline K. 2007. The thylakoid proton gradient promotes an advanced stage of signal peptide binding deep within the Tat pathway receptor complex. J Biol Chem 282:5263–5272. http://dx.doi.org/10.1074/jbc.M610337200. [PubMed]
132. Bageshwar UK, Musser SM. 2007. Two electrical potential-dependent steps are required for transport by the Escherichia coli Tat machinery. J Cell Biol 179:87–99. http://dx.doi.org/10.1083/jcb.200702082. [PubMed]
133. Halbig D, Wiegert T, Blaudeck N, Freudl R, Sprenger GA. 1999. The efficient export of NADP-containing glucose-fructose oxidoreductase to the periplasm of Zymomonas mobilis depends both on an intact twin-arginine motif in the signal peptide and on the generation of a structural export signal induced by cofactor binding. Eur J Biochem 263:543–551. http://dx.doi.org/10.1046/j.1432-1327.1999.00536.x. [PubMed]
134. Matos CFRO, Robinson C, Di Cola A. 2008. The Tat system proofreads FeS protein substrates and directly initiates the disposal of rejected molecules. EMBO J 27:2055–2063. http://dx.doi.org/10.1038/emboj.2008.132. [PubMed]
135. Goosens VJ, Monteferrante CG, van Dijl JM. 2014. Co-factor insertion and disulfide bond requirements for twin-arginine translocase-dependent export of the Bacillus subtilis Rieske protein QcrA. J Biol Chem 289:13124–13131. http://dx.doi.org/10.1074/jbc.M113.529677. [PubMed]
136. Sanders C, Wethkamp N, Lill H. 2001. Transport of cytochrome c derivatives by the bacterial Tat protein translocation system. Mol Microbiol 41:241–246. http://dx.doi.org/10.1046/j.1365-2958.2001.02514.x. [PubMed]
137. Sutherland GA, Grayson KJ, Adams NBP, Mermans DMJ, Jones AS, Robertson AJ, Auman DB, Brindley AA, Sterpone F, Tuffery P, Derreumaux P, Dutton PL, Robinson C, Hitchcock A, Hunter CN. 2018. Probing the quality control mechanism of the Escherichia coli twin-arginine translocase with folding variants of a de novo-designed heme protein. J Biol Chem 293:6672–6681. http://dx.doi.org/10.1074/jbc.RA117.000880. [PubMed]
138. Barnett JP, van der Ploeg R, Eijlander RT, Nenninger A, Mendel S, Rozeboom R, Kuipers OP, van Dijl JM, Robinson C. 2009. The twin-arginine translocation (Tat) systems from Bacillus subtilis display a conserved mode of complex organization and similar substrate recognition requirements. FEBS J 276:232–243. http://dx.doi.org/10.1111/j.1742-4658.2008.06776.x. [PubMed]
139. Kolkman MA, van der Ploeg R, Bertels M, van Dijk M, van der Laan J, van Dijl JM, Ferrari E. 2008. The twin-arginine signal peptide of Bacillus subtilis YwbN can direct either Tat- or Sec-dependent secretion of different cargo proteins: secretion of active subtilisin via the B. subtilis Tat pathway. Appl Environ Microbiol 74:7507–7513. http://dx.doi.org/10.1128/AEM.01401-08. [PubMed]
140. Austerberry JI, Dajani R, Panova S, Roberts D, Golovanov AP, Pluen A, van der Walle CF, Uddin S, Warwicker J, Derrick JP, Curtis R. 2017. The effect of charge mutations on the stability and aggregation of a human single chain Fv fragment. Eur J Pharm Biopharm 115:18–30. http://dx.doi.org/10.1016/j.ejpb.2017.01.019. [PubMed]
141. Jones AS, Austerberry JI, Dajani R, Warwicker J, Curtis R, Derrick JP, Robinson C. 2016. Proofreading of substrate structure by the twin-arginine translocase is highly dependent on substrate conformational flexibility but surprisingly tolerant of surface charge and hydrophobicity changes. Biochim Biophys Acta 1863:3116–3124. http://dx.doi.org/10.1016/j.bbamcr.2016.09.006. [PubMed]
142. Panahandeh S, Maurer C, Moser M, DeLisa MP, Müller M. 2008. Following the path of a twin-arginine precursor along the TatABC translocase of Escherichia coli. J Biol Chem 283:33267–33275. http://dx.doi.org/10.1074/jbc.M804225200. [PubMed]
143. Stolle P, Hou B, Brüser T. 2016. The Tat substrate CueO is transported in an incomplete folding state. J Biol Chem 291:13520–13528. http://dx.doi.org/10.1074/jbc.M116.729103. [PubMed]
144. Cline K, McCaffery M. 2007. Evidence for a dynamic and transient pathway through the TAT protein transport machinery. EMBO J 26:3039–3049. http://dx.doi.org/10.1038/sj.emboj.7601759. [PubMed]
145. Richter S, Lindenstrauss U, Lücke C, Bayliss R, Brüser T. 2007. Functional Tat transport of unstructured, small, hydrophilic proteins. J Biol Chem 282:33257–33264. http://dx.doi.org/10.1074/jbc.M703303200. [PubMed]
146. Lindenstrauss U, Brüser T. 2009. Tat transport of linker-containing proteins in Escherichia coli. FEMS Microbiol Lett 295:135–140. http://dx.doi.org/10.1111/j.1574-6968.2009.01600.x. [PubMed]
147. Rocco MA, Waraho-Zhmayev D, DeLisa MP. 2012. Twin-arginine translocase mutations that suppress folding quality control and permit export of misfolded substrate proteins. Proc Natl Acad Sci U S A 109:13392–13397. http://dx.doi.org/10.1073/pnas.1210140109. [PubMed]
148. Turner RJ, Papish AL, Sargent F. 2004. Sequence analysis of bacterial redox enzyme maturation proteins (REMPs). Can J Microbiol 50:225–238. http://dx.doi.org/10.1139/w03-117. [PubMed]
149. Tranier S, Mortier-Barrière I, Ilbert M, Birck C, Iobbi-Nivol C, Méjean V, Samama JP. 2002. Characterization and multiple molecular forms of TorD from Shewanella massilia, the putative chaperone of the molybdoenzyme TorA. Protein Sci 11:2148–2157. http://dx.doi.org/10.1110/ps.0202902. [PubMed]
150. Chan CS, Chang L, Rommens KL, Turner RJ. 2009. Differential interactions between Tat-specific redox enzyme peptides and their chaperones. J Bacteriol 191:2091–2101. http://dx.doi.org/10.1128/JB.00949-08. [PubMed]
151. Monteferrante CG, MacKichan C, Marchadier E, Prejean MV, Carballido-López R, van Dijl JM. 2013. Mapping the twin-arginine protein translocation network of Bacillus subtilis. Proteomics 13:800–811. http://dx.doi.org/10.1002/pmic.201200416. [PubMed]
152. Krishnappa L, Monteferrante CG, van Dijl JM. 2012. Degradation of the twin-arginine translocation substrate YwbN by extracytoplasmic proteases of Bacillus subtilis. Appl Environ Microbiol 78:7801–7804. http://dx.doi.org/10.1128/AEM.02023-12. [PubMed]
153. Overton TW. 2014. Recombinant protein production in bacterial hosts. Drug Discov Today 19:590–601. http://dx.doi.org/10.1016/j.drudis.2013.11.008. [PubMed]
154. Pooley HM, Merchante R, Karamata D. 1996. Overall protein content and induced enzyme components of the periplasm of Bacillus subtilis. Microb Drug Resist 2:9–15. [PubMed]
155. van Dijl JM, Braun PG, Robinson C, Quax WJ, Antelmann H, Hecker M, Müller J, Tjalsma H, Bron S, Jongbloed JD. 2002. Functional genomic analysis of the Bacillus subtilis Tat pathway for protein secretion. J Biotechnol 98:243–254. http://dx.doi.org/10.1016/S0168-1656(02)00135-9.
156. Dröge MJ, Boersma YL, Braun PG, Buining RJ, Julsing MK, Selles KGA, van Dijl JM, Quax WJ. 2006. Phage display of an intracellular carboxylesterase of Bacillus subtilis: comparison of Sec and Tat pathway export capabilities. Appl Environ Microbiol 72:4589–4595. http://dx.doi.org/10.1128/AEM.02750-05. [PubMed]
157. Goosens VJ, van Dijl JM.2017. Twin-arginine protein translocation. Curr Top Microbiol Immunol 404:69–94. [PubMed]
158. French C, Keshavarz-Moore E, Ward JM. 1996. Development of a simple method for the recovery of recombinant proteins from the Escherichia coli periplasm. Enzyme Microb Technol 19:332–338. http://dx.doi.org/10.1016/S0141-0229(96)00003-8.
159. Matos CFRO, Robinson C, Alanen HI, Prus P, Uchida Y, Ruddock LW, Freedman RB, Keshavarz-Moore E. 2014. Efficient export of prefolded, disulfide-bonded recombinant proteins to the periplasm by the Tat pathway in Escherichia coli CyDisCo strains. Biotechnol Prog 30:281–290. http://dx.doi.org/10.1002/btpr.1858. [PubMed]
160. Browning DF, Richards KL, Peswani AR, Roobol J, Busby SJW, Robinson C. 2017. Escherichia coli “TatExpress” strains super-secrete human growth hormone into the bacterial periplasm by the Tat pathway. Biotechnol Bioeng 114:2828–2836. http://dx.doi.org/10.1002/bit.26434. [PubMed]
161. Albiniak AM, Matos CFRO, Branston SD, Freedman RB, Keshavarz-Moore E, Robinson C. 2013. High-level secretion of a recombinant protein to the culture medium with a Bacillus subtilis twin-arginine translocation system in Escherichia coli. FEBS J 280:3810–3821. http://dx.doi.org/10.1111/febs.12376. [PubMed]
162. Behrendt J, Lindenstrauss U, Brüser T. 2007. The TatBC complex formation suppresses a modular TatB-multimerization in Escherichia coli. FEBS Lett 581:4085–4090. http://dx.doi.org/10.1016/j.febslet.2007.07.045. [PubMed]
163. journal-id:

Article metrics loading...



The Tat pathway for protein translocation across bacterial membranes stands out for its selective handling of fully folded cargo proteins. In this review, we provide a comprehensive summary of our current understanding of the different known Tat components, their assembly into different complexes, and their specific roles in the protein translocation process. In particular, this overview focuses on the Gram-negative bacterium and the Gram-positive bacterium . Using these organisms as examples, we discuss structural features of Tat complexes alongside mechanistic models that allow for the Tat pathway’s unique protein proofreading and transport capabilities. Finally, we highlight recent advances in exploiting the Tat pathway for biotechnological benefit, the production of high-value pharmaceutical proteins.

Highlighted Text: Show | Hide
Loading full text...

Full text loading...

Comment has been disabled for this content
Submit comment
Comment moderation successfully completed


Image of Figure 1
Figure 1

Proteins always originate from translating ribosomes (R). Their N-terminal signal peptide (OmpA or TorA in this overview) directs the nascent polypeptide chain to the correct translocase (Sec or Tat, respectively), which may be aided by chaperones. The unfolded Sec protein is transferred to SecA, where it is threaded through the SecYEG channel in the plasma membrane, powered by repeated cycles of ATP binding and hydrolysis. In the oxidizing periplasm, the unfolded protein assumes its tertiary fully folded state. The Tat-dependently translocated protein is fully folded within the cytoplasm, where it may also acquire its cofactor. Once directed to TatBC, TatA protomers are recruited to translocate the protein across the cytoplasmic membrane. Energy required for this process is created by the PMF. mRNA molecules are schematically represented by an interrupted line, synthesized proteins by uninterrupted lines, and translocase subunits by cylinders.

Citation: Frain K, van Dijl J, Robinson C. 2019. The Twin-Arginine Pathway for Protein Secretion, EcoSal Plus 2019; doi:10.1128/ecosalplus.ESP-0040-2018
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 2
Figure 2

The structure of Tat and Sec signal peptides includes three regions, namely, a basic N domain, a hydrophobic H domain, and a polar C domain. A signal peptidase cleavage site (AxA) is positioned prior to the mature protein. The amino acid sequences of the TorA and OmpA signal peptides are specified. Tat signal peptides (top) have a consensus motif containing twin arginines, while Sec signal peptides do not contain this motif. Sec signal peptides tend to be shorter, with fewer residues in their N and H domains, than Tat signal peptides.

Citation: Frain K, van Dijl J, Robinson C. 2019. The Twin-Arginine Pathway for Protein Secretion, EcoSal Plus 2019; doi:10.1128/ecosalplus.ESP-0040-2018
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 3
Figure 3

Three essential components form the Gram-negative bacterial Tat complex, namely, TatA, TatB, and TatC. TatA/E and TatB have similar topologies in that they have one TM helix domain with a short periplasmic N-terminal region, a tilted APH, and an unstructured C terminus on the cytoplasmic side of the plasma membrane. Notably, TatB is larger than TatA, with a longer C-terminal tail. TatC is significantly bigger, as it contains 6 membrane-embedded helices with both the C- and N-terminal ends residing in the cytoplasm. Helices 5 and 6 do not fully span the membrane, which may contribute to TatC’s function.

Citation: Frain K, van Dijl J, Robinson C. 2019. The Twin-Arginine Pathway for Protein Secretion, EcoSal Plus 2019; doi:10.1128/ecosalplus.ESP-0040-2018
Permissions and Reprints Request Permissions
Download as Powerpoint


Generic image for table
Table 1

Molecular masses of Tat proteins and complexes in and

Citation: Frain K, van Dijl J, Robinson C. 2019. The Twin-Arginine Pathway for Protein Secretion, EcoSal Plus 2019; doi:10.1128/ecosalplus.ESP-0040-2018

Supplemental Material

No supplementary material available for this content.

This is a required field
Please enter a valid email address
Please check the format of the address you have entered.
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error