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Professor Colin Robinson

Professor in Biotechnology/Head of School

School of Biosciences


Professor Colin Robinson joined the School of Biosciences in 2013. He studied Biochemistry as an undergraduate at the University of Edinburgh and went on to carry out a PhD studying chloroplast protein targeting with John Ellis at the University of Warwick. This generated a long-standing interest in protein targeting systems which has remained a dominant interest in the research group.  After completing his PhD he spent 2 years at the University of Munich studying mitochondrial protein targeting with Professor Walter Neupert. He then returned to Warwick as a lecturer in 1985 and spent the next 27 years at Warwick as Lecturer, Senior lecturer and finally Professor.  His work initially focused on chloroplast protein targeting pathways, particularly those located in thylakoid membranes, but the group’s focus shifted to bacterial systems in more recent years.

Colin is a member of the Industrial Biotechnology and Synthetic Biology Group and the Industrial Biotechnology Cenre

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Also view these in the Kent Academic Repository

Smith, S. et al. (2017). TatA complexes exhibit a marked change in organisation in response to expression of the TatBC complex. Biochemical Journal [Online]:BCJ20160952. Available at:
Jones, A. et al. (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. Biochimica et Biophysica Acta (BBA) - Molecular Cell Research [Online] 1863:3116-3124. Available at:
Zedler, J., Mullineaux, C. and Robinson, C. (2016). Efficient targeting of recombinant proteins to the thylakoid lumen in Chlamydomonas reinhardtii using a bacterial Tat signal peptide. Algal Research [Online] 19:57-62. Available at:
Frain, K. et al. (2016). The Bacillus subtilis TatAdCd system exhibits an extreme level of substrate selectivity. Biochimica et Biophysica Acta (BBA) - Molecular Cell Research [Online] 1864:202-208. Available at:
Zedler, J. et al. (2015). Stable expression of a bifunctional diterpene synthase in the chloroplast of Chlamydomonas reinhardtii. Journal of Applied Phycology [Online] 27:2271-2277. Available at:
Alanen, H. et al. (2015). Efficient export of human growth hormone, interferon alpha2b and antibody fragments to the periplasm by the Escherichia coli Tat pathway in the absence of prior disulfide bond formation. Biochimica et Biophysica Acta (BBA) - Molecular Cell Research [Online] 1853:756-763. Available at:
Gangl, D. et al. (2015). Biotechnological exploitation of microalgae. Journal of Experimental Botany [Online] 66:6975-6990. Available at:
Gangl, D. et al. (2015). Expression and membrane-targeting of an active plant cytochrome P450 in the chloroplast of the green alga Chlamydomonas reinhardtii. Phytochemistry [Online] 110:22-28. Available at:
Patel, R., Smith, S. and Robinson, C. (2014). Protein transport by the bacterial Tat pathway. Biochimica et Biophysica Acta (BBA) - Molecular Cell Research [Online] 1843:1620-1628. Available at:
Patel, R. et al. (2014). A mutation leading to super-assembly of twin-arginine translocase (Tat) protein complexes. Biochimica et Biophysica Acta (BBA) - Molecular Cell Research [Online] 1843:1978-1986. Available at:
Matos, C. et al. (2014). Efficient export of prefolded, disulfide-bonded recombinant proteins to the periplasm by the Tat pathway in Escherichia coli CyDisCo strains. Biotechnology Progress [Online] 30:281-290. Available at:
Albiniak, A. et al. (2013). High-level secretion of a recombinant protein to the culture medium with aBacillus subtilistwin-arginine translocation system inEscherichia coli. FEBS Journal [Online] 280:3810-3821. Available at:
McKelvey, K. et al. (2013). Fabrication, Characterization, and Functionalization of Dual Carbon Electrodes as Probes for Scanning Electrochemical Microscopy (SECM). Analytical Chemistry [Online] 85:7519-7526. Available at:
McKelvey, K. et al. (2013). Quantitative Local Photosynthetic Flux Measurements at Isolated Chloroplasts and Thylakoid Membranes Using Scanning Electrochemical Microscopy (SECM). Journal of Physical Chemistry B [Online] 117:7878-7888. Available at:
Matos, C. et al. (2013). Efficient export of prefolded, disulfide-bonded recombinant proteins to the periplasm by the Tat pathway inEscherichia coliCyDisCo strains. Biotechnology Progress [Online] 30:281-290. Available at:
Beck, D. et al. (2013). Ultrastructural characterisation of Bacillus subtilis TatA complexes suggests they are too small to form homooligomeric translocation pores. Biochimica et Biophysica Acta (BBA) - Molecular Cell Research [Online] 1833:1811-1819. Available at:
Ren, C., Patel, R. and Robinson, C. (2013). Exclusively membrane-inserted state of an uncleavable Tat precursor protein suggests lateral transfer into the bilayer from the translocon. FEBS Journal [Online] 280:3354-3364. Available at:
Monteferrante, C. et al. (2012). TatAc, the Third TatA Subunit of Bacillus subtilis, Can Form Active Twin-Arginine Translocases with the TatCd and TatCy Subunits. Applied and Environmental Microbiology [Online] 78:4999-5001. Available at:
Baglieri, J. et al. (2012). Structure of TatA Paralog, TatE, Suggests a Structurally Homogeneous Form of Tat Protein Translocase That Transports Folded Proteins of Differing Diameter. Journal of Biological Chemistry [Online] 287:7335-7344. Available at:
Matos, C. et al. (2012). High-yield export of a native heterologous protein to the periplasm by the tat translocation pathway in Escherichia coli. Biotechnology and Bioengineering [Online] 109:2533-2542. Available at:
van der Ploeg, R. et al. (2012). High-Salinity Growth Conditions Promote Tat-Independent Secretion of Tat Substrates in Bacillus subtilis. Applied and Environmental Microbiology [Online] 78:7733-7744. Available at:
Albiniak, A., Baglieri, J. and Robinson, C. (2012). Targeting of lumenal proteins across the thylakoid membrane. Journal of Experimental Botany [Online] 63:1689-1698. Available at:
Barnett, J. et al. (2011). The Tat protein export pathway and its role in cyanobacterial metalloprotein biosynthesis. FEMS Microbiology Letters [Online] 325:1-9. Available at:
Branston, S. et al. (2011). Investigation of the impact of Tat export pathway enhancement on E. coli culture, protein production and early stage recovery. Biotechnology and Bioengineering [Online] 109:983-991. Available at:
Cain, P. et al. (2011). Binding of chloroplast signal recognition particle to a thylakoid membrane protein substrate in aqueous solution and delineation of the cpSRP43substrate interaction domain. Biochemical Journal [Online] 437:149-155. Available at:
Robinson, C. et al. (2011). Transport and proofreading of proteins by the twin-arginine translocation (Tat) system in bacteria. Biochimica Et Biophysica Acta-Biomembranes [Online] 1808:876-884. Available at:
Barnett, J. et al. (2011). Expression of the bifunctional Bacillus subtilis TatAd protein in Escherichia coli reveals distinct TatA/B-family and TatB-specific domains. Archives of Microbiology [Online] 193:583-594. Available at:
van der Ploeg, R. et al. (2011). Salt Sensitivity of Minimal Twin Arginine Translocases. Journal of Biological Chemistry [Online] 286:43759-43770. Available at:
Warren, G. et al. (2009). Contributions of the Transmembrane Domain and a Key Acidic Motif to Assembly and Function of the TatA Complex. Journal of Molecular Biology [Online] 388:122-132. Available at:
Barnett, J. et al. (2009). The twin-arginine translocation (Tat) systems from Bacillus subtilis display a conserved mode of complex organization and similar substrate recognition requirements. FEBS Journal [Online] 276:232-243. Available at:
Matos, C., Di Cola, A. and Robinson, C. (2009). TatD is a central component of a Tat translocon-initiated quality control system for exported FeS proteins in Escherichia coli. EMBO Reports [Online] 10:474-479. Available at:
Aldridge, C., Cain, P. and Robinson, C. (2009). Protein transport in organelles: Protein transport into and across the thylakoid membrane. FEBS Journal [Online] 276:1177-1186. Available at:
Cain, P. et al. (2009). A novel extended family of stromal thioredoxins. Plant Molecular Biology [Online] 70:273-281. Available at:
Vladimirou, E. et al. (2009). Diffusion of a membrane protein, Tat subunit Hcf106, is highly restricted within the chloroplast thylakoid network. FEBS Letters [Online] 583:3690-3696. Available at:
Puthiyaveetil, S. et al. (2008). The ancestral symbiont sensor kinase CSK links photosynthesis with gene expression in chloroplasts. Proceedings of the National Academy of Sciences [Online] 105:10061-10066. Available at:
Aldridge, C. et al. (2008). Tat-dependent targeting of Rieske iron-sulphur proteins to both the plasma and thylakoid membranes in the cyanobacterium Synechocystis PCC6803. Molecular Microbiology [Online] 70:140-150. Available at:
Barnett, J. et al. (2008). A minimal Tat system from a gram-positive organism: a bifunctional TatA subunit participates in discrete TatAC and TatA complexes. Journal of Biological Chemistry [Online] 283:2534-2542. Available at:
Stengel, K. et al. (2008). Structural Basis for Specific Substrate Recognition by the Chloroplast Signal Recognition Particle Protein cpSRP43. Science [Online] 321:253-256. Available at:
Matos, C., Robinson, C. and Di Cola, A. (2008). The Tat system proofreads FeS protein substrates and directly initiates the disposal of rejected molecules. Embo Journal [Online] 27:2055-2063. Available at:
Mendel, S. et al. (2008). The Escherichia coli TatABC system and a Bacillus subtilis TatAC-type system recognise three distinct targeting determinants in twin-arginine signal peptides. Journal of Molecular Biology [Online] 375:661-72. Available at:
Showing 40 of 42 total publications in KAR. [See all in KAR]
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Understanding and exploiting (i) protein transport systems in bacteria and chloroplasts, and (ii) pathways for high-value products in microalgae

Protein transport systems

Much our research is focused on the mechanisms by which proteins are transported into and across biological membranes. In particular, we are interested in bacterial protein export. Bacteria export numerous proteins into the periplasm (Gram-negative species) or the cell wall/medium (Gram-positives) and the underlying mechanisms have been studied in great detail. Many proteins are exported using the Sec-dependent pathway, in which substrates are 'threaded' through the membrane-bound Sec translocon in an unfolded state. Other proteins are exported by the twin-arginine translocation, or Tat pathway. In this pathway, substrates are synthesised with N-terminal signal peptides containing a key twin-arginine motif. The proteins are then transported by a membrane-bound Tat translocon which is uniquely able to transport fully folded proteins - even oligomeric proteins - across the tightly coupled plasma membrane. Ongoing projects are aimed at understanding how this is achieved, and how the system can be expolited for the production of high-value therapeutic proteins.

Exploiting microalgae

Microalgae (which we define here as cyanobacteria and unicellular eukaryotic algae) hold great promise for the biotechnology industry. They divide rapidly, can be grown under phototrophic conditions, and contain a variety of high-value compounds including colourants and oils. However, they also have real potential as cell factories. As part of a large EU-funded consortium, we are developing strains that express pathways for high-value compounds, using the cyanobacterium Synechocystis PCC6803 and the alga Chlamydomonas reinhardtii as host organisms. We are also expressing high-value biotherapeutics in Chlamydomonas in order to assess this organism's potential as a protein production host.

Current Projects:

New IB Catalyst project to develop a suite of new tools for production of recombinant proteins in E. coli


Over a third of licensed biopharmaceuticals are produced in Escherichia coli and there is a need to develop new production methods to maintain the UK's competitive edge. The Industrial Biotechnology Catalyst programme is a BBSRC/Innovate UK/EPRSC venture to support larger-scale biotechnology projects in the UK. Prof Colin Robinson is co-ordinator of the project entitled 'A new generation of E. coli expression hosts and tools for recombinant protein production'. This £2.6 million grant funds research at the Universities of Kent, Birmingham and Sheffield. The project also has industrial links with MedImmune, Fuji-Diosynth, Cobra, and UCB.

The primary objective of this project is to develop an integrated E. coli production platform for biopharmaceutical production, incorporating innovations at key stages including product synthesis, folding, export to the periplasm and release to the culture medium. This will provide industry with a powerful alternative to current strategies, most of which are based on decades-old technology. These innovations will have a long-lasting effect on the UK's ability to compete within a market that is currently worth in excess of $100 billion p.a.

The groups involved are as follows:

(WP 1). Production of proteins in a highly regulated manner (Busby group - Birmingham)
(WP 2). Export of proteins from the cytoplasm to the periplasm (Robinson group - Kent)
(WP 3). Characterisation of production strains using advanced proteomics (Wright group - Sheffield)
(WP 4). Release of target proteins from the periplasm (Dafforn group - Birmingham)
(WP 5). Industrial validation (Smales group - Kent)

The bacterial and plant Tat systems - unique mechanism and remarkable 'proofreading' abilites

The unique nature of the Tat mechanism has prompted great interest in the system and we are studying the mechanism (poorly defined so far) the structure of the membrane bound Tat complexes and the 'proofreading' of substrates. Some Tat substrates need to be exported in a properly folded state because they bind complex redox cofactors in the cytoplasm (for example, FeS centres). The system has to be able to 'know' when the substrate is fully folded and with the cofactors in place before it is exported, and recent evidence suggests that this is a complex process. We are using a combination of approaches to dissect the proofreading mechanism and understand this system further.

Exploitation of the Tat system for biotechnological purposes

In BBSRC-funded BRIC and IPA projects, we are working with collaborators at UCL and Oulu (Finland) to develop the Tat system into a biotechnological tool. Many high-value biopharmaceuticals are currently prepared by expression in E. coli and export to the periplasm using the Sec export pathway. Many antibody fragments, for example, are prepared in this manner, and this is now a multi-billion dollar industry. The advantages of this method are: (i) it is easier to purify the target protein from the periplasm and (ii) the periplasm is an oxidising environment - essential for disulphide bond formation. Unfortunately, many heterologous proteins cannot be exported to the periplasm even when a Sec signal peptide is present; this is usually because they fold too quickly, or too tightly, for the Sec system to handle.

The Tat pathway represents a powerful alternative means of exporting proteins to the periplasm. Several studies have shown that heterologous proteins can be exported by attachment of an N-terminal twin-arginine signal peptide, and its ability to export folded proteins means that it may well be able to export a wide range of 'difficult' passenger proteins. Our present studies are aimed at maximising the Tat-dependent export capabilities of the E. coli system and there is now clear evidence that Tat-based export systems have massive potential for the production of recombinat proteins. We have also shown that disulphide-bonded proteins can be exported with high efficiency, especially when expressed in strains that permit the formation of these bonds in the cytoplasm.

New Marie Skłodowska-Curie project, 'ProteinFactory'

The Robinson group is a partner in a newly-awarded MSCA actions Innovative Training Network, 'ProteinFactory'. The project aims to understand and exploit protein export systems in Gram-negative and –positive organisms, in order to develop next-generation secretion platforms. The project involves collaboration withn 9 other research groups and companies throughout Europe, and starts in September 2015.

Synthesis of high-value natural products in microalgae

Many plant natural products are used for therapeutic and other purposes, and one class of products is of particular interest: terpenoids. These are complex plant products, many of which are used by the biotechnology, cosmetic and other industries. There are two key problems: (i) they are usually present in minute quantities in the native plant and (ii) they are almost invariably difficult (often impossible) to synthesise by chemical means. As part of an EU-funded project, 'Photo.comm' we are working with Copenhagen University to express pathways for diterpenoid synthesis in cyanobacteria and Chlamydomonas reinhardtii. The work also involves collaboration with a range of algal experts in the UK, including Saul Purton (UCL) and Alison Smith (Cambridge).



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Research Technicians:

  • Connor Webb
  • Amber Peswani

Phd students:

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Monopoly poster entry for FIREBio: pdf version



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Enquiries: Phone: +44 (0)1227 823743

School of Biosciences, University of Kent, Canterbury, Kent, CT2 7NJ

Last Updated: 04/01/2017