Department of Pharmacy and Pharmacology

matthew_lloyd

Senior Lecturer in Molecular Enzymology

5 West - 2.13

Email:  M.D.Lloyd@bath.ac.uk

Tel: +44 (0) 1225 386786 

 

Dr Matthew Lloyd 

Profile

2002 Lecturer in Molecular Enzymology (University of Bath)
1995-2001 Senior Post-Doctoral Research Associate (University of Oxford)
1993-1994 Post-Doctoral Research Associate (Brown University)
1989-1992 D.Phil. 'Biosynthesis of Clavulanic acid' (University of Oxford)
1986-1989 Bsc (hons) Biological Chemistry (University of Leicester)

Research Interests

Research in my group is aimed at understanding the in vivo role of proteins in metabolism in normal cells and diseases such as cancer. The work utilizes a wide range of different techniques, including molecular biology, expression and purification of recombinant proteins, activity assays, chemical rescue, steady-state kinetic analysis, and isolation of products and spectroscopic characterization.

Branched-chain fatty acid metabolism

With Professor M. D. Threadgill, Department of Pharmacy & Pharmacology, University of Bath.

Branched-chain fatty acids are common in the human diet, and related structures are common in dietary supplements and occur in some drugs, e.g. ibuprofen (Scheme 1). The most common branched-chain fatty acid in the human diet is phytanic acid, and is found in some meats and dairy products. Due to the presence of a 3-methyl group phytanic acid cannot be degraded by the usual b -oxidation route, and is processed by a preliminary a -oxidation pathway within peroxisomes to give pristanic acid. Defects in this pathway give rise to a rare inherited condition known as Adult Refsum's disease (ARD), whose symptoms include blindness, deafness, loss of sense of smell and taste amongst others. Work in my group has studied one of the defective proteins causing ARD (phytanoyl-CoA 2-hydroxylase, known as PAHX or PhyH), and determined the effects of these changes.

We have also studied fatty aldehydes dehydrogenase (ALDH10) , an enzyme involved in converting the chlorophyll sidechain to phytanic acid and the metabolism of a wide range of long-chain fatty alcohols.


Scheme 1: Peroxisomal degradation of phytanic acid to pristanic acid.

Recently a link has been shown between levels of dietary phytanic acid and prostate cancer in men. A particular protein,a-methylacyl-CoA racemase (AMACR), exists in several forms and the amount of AMACR is increased in prostate cancer. The normal function of AMACR is to invert the 2R-isomer of pristanic acid (as the coenzyme A ester) to its 2S form so that it can be further processed by b-oxidation (Scheme 1).

Funding from Cancer Research U.K. (http://science.cancerresearchuk.org/) has been obtained to study AMACR as a potential anti-prostate cancer target at Bath University.

Pin 1 as a target anti-cancer target

With Professor M. D. Threadgill, Department of Pharmacy & Pharmacology, University of Bath

Mechanism of cis-trans interconversion catalysed by Pin-1

Pin 1 catalyzes the interconversion of cis and trans conformers of peptides containing phosphoserine-proline and phosphothreonine-proline sequences. At least twenty proteins are substrates for Pin 1 isomerase activity; many of these are involved in replication, apoptosis or cell cycle control. Cis/trans isomerization appears to be to be essential for tumour cell survival and entry into mitosis, so Pin 1 is a good target for drug design and development in the treatment of cancer. We have recently started a project, funded by Cancer Research UK (http://science.cancerresearchuk.org/), to design, synthesize and test selective reversible and irreversible inhibitors of this enzyme.

Carbonic anhydrase inhibitors

With Professor Barry V. L. Potter, Department of Pharmacy & Pharmacology, and Professor K. Ravi Acharya, Department of Biology & Biochemistry, University of Bath.

Carbonic anhydrase (CA) is a zinc-dependent enzyme that catalyses the reversible hydration of carbon dioxide to carbonic acid, which can then be converted to hydrogen carbonate and carbonate. Humans contain at least 14 different isoforms of CA, and these are involved in maintaining pH and fluid balance. The various isoforms are attractive targets for diseases such as glaucoma, cancer and obesity.

Recent work in Professor Potter's group has shown that some types of anti-breast cancer drugs bind to CA II (the predominant form in red blood cells) and this can result in high bio-availability and also stabilizes and protects the drug. Together we have characterized this phenomenon by determining the crystal structures of three drugs bound to human CAII. The first of these drugs was 667-COUMATE .

Structure of 667-coumate bound to CAII (9)
Structure of 667-coumate bound to CAII
Binding of 667-COUMATE within the CAII active site (9). Key interactions are shown with blue lines, with bond distances in Å.
Binding of 667-COUMATE within the CAII active site . Key interactions are shown with blue lines, with bond distances in Ǻ

The second and third drugs for which structures were determined bound to CAII were dual aromatase-steroid sulfatase (DASI) inhibitors . Despite the two DASI inhibitors having similar structures, the mode of binding to CAII was quite different. The results suggest that binding to CAII could be a general methodology for efficient delivery of this class of drugs. Other drug targets are being investigated using this structure-based approach.

In addition my group has published several papers on structure based drug design, synthesis of inhibitors and the use of enzyme assays to characterise these inhibitors.

Recently, a poster was displayed at the Cancer Research Showcase at the Innovation Centre, Bath on 13th May 2011.

Publications

  1. T. J. Woodman, P. J. Wood, A. S. Thompson, T. Hutchings, P. Jiao, G. R. Steel, M. D. Threadgill, M. D. Lloyd, "Chiral inversion of NSAID-CoA esters by human alpha-methylacyl-CoA racemase 1A", Chem. Commun., 2011, DOI:10.1039/C1CC10763A;
     
  2. P. T. Sunderland, E. C. Y. Woon, A. Dhami, A. B. Bergin, M. F. Mahon, P. J. Wood, L. A. Jones, S. R. Tully, M. D. Lloyd, A. S. Thompson, H. Javaid, N. M. B. Martin, M. D. Threadgill, 5-Benzamidoisoquinolin-1-ones and 5-(omega-carboxyalkyl)isoquinolin-1-ones as isoform-selective inhibitors of poly(ADP-ribose)polymerase-2 (PARP-2), 2011, J. Med. Chem. 54, 2049-2059;
     
  3. S. Pilgrim, G. Kociok-Kohn, M. D. Lloyd, S. E. Lewis, "InosAminoAcids": Novel inositol-amino acid hybrid structures accessed by microbial arene oxidation", 2011, Chem. Commun. 47, 4799-4801;
     
  4. K. P. Holbourn, M. D. Lloyd, A.S. Thompson, M. D. Threadgill, K. R. Acharya, 'Cloning, purification, crystallisation and preliminary crystallographic analysis of the human histone deacetylase sirtuin 1, 2011, Acta Crys., F67, 461-463;
     
  5. P. T. Sunderland, A. Dhami, M. F. Mahon, L. A. Jones, S. R. Tully, M. D. Lloyd, A. S. Thompson, H. Javaid, N. B. Martin, M. D. Threadgill, 'Synthesis of 4-alkyl-, 4-aryl-, and arylamino-5-substituted isoquinolin-1-ones and identification of a new PARP-2 selective inhibitor", 2011, Org. Biomol. Chem. 9, 881-891.
     
  6. F. A. Sattar, D. J. Darley, F. Politano, T. J. Woodman, M. D. Threadgill and M. D. Lloyd, "Unexpected stereoselective exchange of straight-chain fatty acyl-CoA alpha-protons by human alpha-methylacyl-CoA racemase 1A (P504S)", 2010, Chem. Commun., 46, 3348-3350
     
  7. G. Cozier, M. Leese, M. D. Lloyd, M. Baker, N. Thiayagarajan, K. R. Acharya and B. V. L. Potter, "Structures of human carbonic anhydrase II/inhibitor complexes reveal a second binding site for steroidal and non-steroidal inhibitors" 2010, Biochemistry, 49, 3464-3476
     
  8. A. Dhami, M. F. Mahon, M. D. Lloyd and M. D. Threadgill, "4-Substituted 5-nitroisoquinolin-1-ones from intramolecular Pd-catalysed reaction of N-(2-alkenyl)-2-halo-3-nitrobenzamides", Tetrahedron, 2009, 65, 4751-4765.
     
  9. A.-M. Lord, M. Mahon, M. D. Lloyd and M. D. Threadgill, “Design, synthesis and evaluation in vitro of quinoline-8-carboxamides, a new class of poly(adenosine-diphosphate-ribose) polymerase-1 (PARP-1) inhibitor”, J. Med. Chem., 2009, 52, 868-877.
     
  10. D. J. Darley, D. S. Butler, S. J. Prideaux, T. W. Thornton, A. D. Wilson, T. J. Woodman, M. D. Threadgill and M. D. Lloyd “Synthesis and use of isotope-labelled substrates for a mechanistic study on human α-methylacyl-CoA racemase 1A (AMACR; P504S)”, Org. Biomol. Chem., 2009, 7, 543-552.
     
  11. A. L. Ball, K. A. Chambers, M. Hewinson, S. Navaratnarajah, L. Samrin, N. Thomas, A. E. H. Tyler, A. J. Wall, M.D. Lloyd, “A microtitre plate assay for measuring glycosidase activity”, J. Enzy. Inhibit. Med. Chem., 2008, 23, 131-135.
     
  12. M. D. Lloyd, D. J. Darley, A. S. Wierzbicki, M. D. Threadgill “α-Methylacyl-CoA racemase: An ‘obscure’ metabolic enzyme takes centre stage”, FEBS J. 2008, 275, 1089-1102.
     
  13.  
  14. M. 6.J. S. W. Kwong, M. F. Mahon, M. D. Lloyd, M. D. Threadgill, “Synthesis of diastereoisomeric homochiral O-protected 4-(arylsulfonimidoyl)butane-1,2,3-triols and conformational and configurational studies”. Tetrahedron, 2007, 12601-12607.
     
  15.  M. D. Lloyd, K. D. E. Boardman, A. Smith, D. M. van den Brink, R. J. A. Wanders, and M. D. Threadgill, “Characterisation of recombinant human aldehyde dehydrogenase 10: Implications for Sjögren-Larsson syndrome”, J. Enzy. Inhibit. Med. Chem., 2007, 22, 584-590.
     
  16. T. Searles, D. Butler, W. Chien, M. Mukherji, M. D. Lloyd and C. J. Schofield, “Studies on the specificity of unprocessed and mature forms of phytanoyl-CoA 2-hydroxylase and mutation of iron-binding residues”, J. Lipid Res., 2005, 46, 1660-1666.
     
  17.  K. R. Acharya and M. D. Lloyd, “The advantages and limitations of protein crystal structures”, Trends in Pharmacological Sciences, 2005, 26, 10-14 (review).
     
  18. M. D. Lloyd, N. Thiyagarajan, Y. T. Ho, L. W. L. Woo, O. B. Sutcliffe, A. Purohit, M. J. Reed, K. R. Acharya, B. V. L. Potter, “First crystal structures of human carbonic anhydrase II in complex with dual aromatase-steroid sulfatase inhibitors”, Biochemistry, 2005, 44, 6858-6866.
     
  19. M.D. Lloyd, R. L. Pedrick, R. Natesh, L. W. L. Woo, A. Purohit, M. J. Reed, K. R. Acharya and B. V. L. Potter, Crystal structure of human carbonic anhydrase II at 1.95 Å resolution in complex with 667-coumate, a novel anti-cancer agent”, Biochem. J., 2005, 385, 715-720.
     
  20. M. D. Lloyd, S. J. Lipscomb, K. S. Hewitson, C. M. H. Hensgens,, J. E. Baldwin, C. J. Schofield, “Controlling the substrate selectivity of deacetoxy/deacetylcephalosporin C synthase”, J. Biol. Chem., 2004, 279, 15420-15426.
     
  21. A. S. Wierzbicki, P. D. Mayne, M. D. Lloyd, D. Burston, G. Mei, M. C. Sidey, M. D. Feher, F. B. Gibberd, “Metabolism of phytanic acid and 3-methyl-adipic acid excretion in patients with Adult Refsum’s disease”, J. Lipid Res., 2003, 44, 1481-1488.
     
  22. H.-J. Lee, Y.-F. Dai, C.-Y. Shiau, C. J. Schofield, M. D. Lloyd, “The kinetic properties of various arginine-258 mutants of deacetoxycephalosporin C synthase”, Eur. J. Biochem., 2003, 270, 1301-1307.
     
  23. S. J. Lipscomb, H.-J. Lee, M. Mukherji, J. E. Baldwin, C. J. Schofield, M. D. Lloyd, “The role of arginine residues in substrate binding and catalysis by deacetoxycephalosporin C synthase”, Eur. J. Biochem., 2002, 269, 2735-2739.
     
  24. M. Mukherji, N. J. Kershaw, C. J. Schofield, A. S. Wierzbicki, M. D. Lloyd, “Utilisation of sterol-carrier-protein-2 by phytanoyl-CoA 2-hydroxylase in the peroxisomal α-oxidation of phytanic acid”, Chemistry & Biology, 2002, 9, 597-605.
     
  25. H. J. Lee, C. J. Schofield, M. D. Lloyd, “Active Site Mutations of Recombinant Deacetoxycephalosporin C Synthase”, Biochem. Biophys. Res. Commun. 2002, 292, 66-70.  .
     
  26.  N. J. Kershaw, M. Mukherji, C. H. MacKinnon, T. W. D. Claridge, B. Odell, A. S. Wierzbicki, M. D. Lloyd, C. J. Schofield “Studies on phytanoyl-CoA 2-hydroxylase (synthesis of phytanoyl-CoA)”, Bioorg. Med. Chem. Letts., 2001, 11, 2545-2548. 
     
  27. C. S. Hamilton, A. Yasuhara, J. E. Baldwin, M. D. Lloyd, P. J. Rutledge “Contrasting fates for 6-α-methylpenicillin N upon oxidation by deacetoxycephalosporin C synthase (DAOCS) and deacetoxy/deacetylcephalosporin C synthase (DAOC/DACS)”, Bioorg. Med. Chem. Letts., 2001, 11, 2511-2514. 
     
  28. M. Mukherji, W. Chien, N. Kershaw, I. J. Clifton, C. J. Schofield, A. S. Wierzbicki, M. D. Lloyd “Structure-function analysis of phytanoyl-CoA 2-hydroxylase mutations causing Refsum’s disease”, Hum. Mol. Gen., 2001, 10, 1971-1982.