Associate Professor Stephen Bell
The screening, engineering and directed evolution of enzymes holds great promise for biotechnological applications. In the lab we study enzymes for biocatalysis and organic synthesis applications. The ultimate goal is to develop these systems as biocatalysts for clean, sustainable, low energy oxidation processes with applications in natural product synthesis (for example generation of valuable flavour and fragrance compounds) and then bioremediation of recalcitrant compounds such as aromatic hydrocarbons.
We engineer cytochrome P450 enzymes to alter their function and identify new enzymes from metabolically diverse bacteria which are capable of binding and oxidising a wide range of organic compounds. We identify new electron transfer partners (e.g. iron-sulphur ferredoxin proteins and flavoproteins) in order to improve the efficiency of the enzymes which is essential for scale-up of their activity. We develop whole cell oxidation systems, which enable the easy screening, scale-up and production of oxygenated organic products.
We are involved in collaborative work with other researchers to
1) to study the mechanism of action of these enzymes which is important in understanding drug metabolism and design
2) Determine the structure of the enzymes by X-ray crystallography and other techniques such as NMR and Mass Spectroscopy
3) Immobilise the enzymes on different solid state supports to enhance their stability and lifetime.
Genome mining and protein engineering of cytochrome P450 enzymes for biocatalysis
The cytochrome P450 superfamily of haem iron monooxygenases is found in virtually all living organisms. They catalyse the oxidation of numerous endogenous and exogenous organic compounds and perform vital functions such as the biosynthesis of steroids and antibiotics and oxidative detoxification of xenobiotics. These monooxygenase enzymes catalyse the insertion of one atom of atmospheric oxygen into a carbon hydrogen bond.
R–H + 2H+ + 2e– + O2 → R–OH + H2O
The screening, engineering and directed evolution of cytochrome P450 enzymes for the oxidation of non-natural substrates holds great promise for biotechnological applications. In the lab we study these cytochrome P450 enzymes and their electron transfer partners for biocatalysis and organic synthesis applications. The ultimate goal is to develop these systems as biocatalysts for clean, sustainable, low energy oxidation processes in natural product synthesis and bioremediation of recalcitrant compounds.
We identify new enzymes from a wide range of bacteria and aim to work out their function and potential applications. This could range from
1) work with designing inhibitors for P450s which play an important role in pathogenic bacteria
2) P450s involved in the synthesis of important secondary metabolites in the bacteria.
We engineer cytochrome P450 enzymes to alter their function and identify new enzymes from metabolically diverse bacteria which are capable of binding and oxidising a wide range of organic compounds. For example we have recently isolated CYP enzymes that are capable of hydroxylating sesquiterpenoids, steroids, alkanes, polyaromatic hydrocarbons and substituted aromatics. We also identify new and engineer existing electron transfer partners (e.g. iron-sulphur ferredoxin proteins and flavoproteins) in order to improve the efficiency of the enzymes which is essential for scale-up of their activity. We also develop whole cell oxidation systems, which enable the easy screening, scale-up and production of oxygenated organic products. We aim to further optimise and scale-up these systems (in vitro and in vivo) using fermentor technology and bioprocess engineering to generate products on a large scale.
This work has led to the formation of a spin out company Oxford Biotrans (http://oxfordbiotrans.com/) which has been set up to use biocatalysis to generate compounds of use to the flavour and fragrance industry.
Students undertake a wider range of activities at the interface of Chemistry and Biochemistry including protein synthesis and engineering (molecular biology), analytical and organic chemistry techniques, enzyme assays structure function studies. Members of the group undertake crystallographic, electrochemical and EPR (electron paramagnetic resonance) studies of these cytochrome P450 enzymes and their electron transfer partners at Adelaide and in collaboration with others. This provides gain a better understanding of different steps in the catalytic cycle and the protein-protein interactions in these systems.
The Australian Research Council are currently funding our research into P450 mechanism through a Discovery Project Grants. My research into isolating and understanding novel P450 electron transfer partners is funded through an ARC Future Fellowship.
My group currently consists of 5 PhD Students and 2 M. Phil Students.
Potential research students are directed to the Adelaide Graduate Centre for information on admissions, applications and scholarship
Questions regarding typical research projects can be directed to Dr Bell.
|2017||Associate Professor and ARC Future Fellow||University of Adelaide|
|2015 - 2016||Senior Lecturer and ARC Future Fellow||University of Adelaide|
|2012 - 2014||Lecturer||University of Adelaide|
|2016||OLT Citation for Outstanding Contributions to Student Learning||University of Adelaide/Australian Government Department of Education and Training|
|2015||ARC Future Fellowship||University of Adelaide|
|2013||Founding Shareholder of Oxford Biotrans|
|University of Oxford||United Kingdom||BA and MA Chemistry (Oxon)|
|Oxford university||United Kingdom||DPhil|
|2017||Maddigan,N, Bell,S, 2017, The self-sufficient CYP102 family enzyme, Krac9955, from Ktedonobacter racemifer DSM44963 acts as an alkyl- and alkyloxy-benzoic acid hydroxylase, Archives of Biochemistry and Biophysics, 615, 15-21 10.1016/j.abb.2016.12.014|
|2017||Hall,EA, Sarkar,MR, Bell,SG, 2017, The selective oxidation of substituted aromatic hydrocarbons and the observation of uncoupling via redox cycling during naphthalene oxidation by the CYP101B1 system, Catal. Sci. Technol., - 10.1039/C7CY00088J|
|2016||Hall,EA, Sarkar,MR, Lee,JHZ, Munday,SD, Bell,SG, 2016, Improving the monooxygenase activity and the regio- and stereoselectivity of terpenoid hydroxylation using ester directing groups, ACS Catalysis, 6, 9, 6306-6317 10.1021/acscatal.6b01882|
|2016||Chao,R, Lau,I, De Voss,J, Bell,S, 2016, Modification of an Enzyme Biocatalyst for the Efficient and Selective Oxidative Demethylation of para-Substituted Benzene Derivatives, ChemCatChem, 8, 23, 3626-3635 10.1002/cctc.201600951|
|2016||Munday,S, Shoji,O, Watanabe,Y, Wong,L, Bell,S, 2016, Improved oxidation of aromatic and aliphatic hydrocarbons using rate enhancing variants of P450Bm3 in combination with decoy molecules, Chemical Communications, 52, 5, 1036-1039 10.1039/C5CC09247G|
|2016||Chao,RR, De Voss,JJ, Bell,SG, 2016, The efficient and selective catalytic oxidation of para-substituted cinnamic acid derivatives by the cytochrome P450 monooxygenase, CYP199A4, RSC Advances, 6, 60, 55286-55297 10.1039/c6ra11025h|
|2016||Coleman,T, Chao,R, De Voss,J, Bell,S, 2016, The importance of the benzoic acid carboxylate moiety for substrate recognition by CYP199A4 from Rhodopseudomonas palustris HaA2, Biochimica et Biophysica Acta - Proteins and Proteomics, 1864, 6, 667-675 10.1016/j.bbapap.2016.03.006|
|2016||Munday,S, Maddigan,N, Young,R, Bell,S, 2016, Characterisation of two self-sufficient CYP102 family monooxygenases from Ktedonobacter racemifer DSM44963 which have new fatty acid alcohol product profiles, Biochimica et Biophysica Acta - General Subjects, 1860, 6, 1149-1162 10.1016/j.bbagen.2016.01.023|
|2016||Bell,S, Hall,E, Sarkar,M, Dasgupta,S, 2016, The Use of Directing Groups Enables the Selective and Efficient Biocatalytic Oxidation of Unactivated Adamantyl C-H Bonds, Chemistry Select, 1, 21, 6700-6707 10.1002/slct.201601615|
|2016||Stok,JE, Hall,EA, Stone,ISJ, Noble,MC, Wong,SH, Bell,SG, De Voss,JJ, 2016, In vivo and in vitro hydroxylation of cineole and camphor by cytochromes P450CYP101A1, CYP101B1 and N242A CYP176A1, Journal of Molecular Catalysis B: Enzymatic, 128, 52-64 10.1016/j.molcatb.2016.03.004|
|2016||Munday,SD, Dezvarei,S, Bell,SG, 2016, Increasing the activity and efficiency of stereoselective oxidations by using decoy molecules in combination with rate-enhancing variants of P450Bm3, ChemCatChem, 8, 17, 2789-2796 10.1002/cctc.201600551|
|2016||Liang,K, Coghlan,C, Bell,S, Doonan,C, Falcaro,P, 2016, Enzyme encapsulation in zeolitic imidazolate frameworks: a comparison between controlled co-precipitation and biomimetic mineralisation, Chemical Communications, 52, 3, 473-476 10.1039/C5CC07577G|
|2015||Zhang,A, Zhang,T, Hall,E, Hutchinson,S, Cryle,M, Wong,L, Zhou,W, Bell,S, 2015, The crystal structure of the versatile cytochrome P450 enzyme CYP109B1 from Bacillus subtilis, Molecular BioSystems, 11, 3, 869-881 10.1039/c4mb00665h|
|2015||Williamson,N, Huang,D, Bell,S, Metha,G, 2015, Guided inquiry learning in an introductory chemistry course, International Journal of Innovation in Science and Mathematics Education, 23, 6, 34-51|
|2015||Coleman,T, Chao,RR, Bruning,JB, De Voss,JJ, Bell,SG, 2015, CYP199A4 catalyses the efficient demethylation and demethenylation of para-substituted benzoic acid derivatives, RSC Advances, 5, 64, 52007-52018 10.1039/c5ra08730a|
|2015||Liang,K, Ricco,R, Doherty,CM, Styles,MJ, Bell,S, Kirby,N, Mudie,S, Haylock,D, Hill,AJ, Doonan,CJ et al, 2015, Biomimetic mineralization of metal-organic frameworks as protective coatings for biomacromolecules, Nature Communications, 6, 1-8 10.1038/ncomms8240|
|2015||Hall,E, Bell,S, 2015, The efficient and selective biocatalytic oxidation of norisoprenoid and aromatic substrates by CYP101B1 from Novosphingobium aromaticivorans DSM12444, RSC Advances, 5, 8, 5762-5773 10.1039/c4ra14010a|
|2014||Zhang,T, Zhang,A, Bell,S, Wong,L, Zhou,W, 2014, The structure of a novel electron-transfer ferredoxin from Rhodopseudomonas palustris HaA2 which contains a histidine residue in its iron-sulfur cluster-binding motif, Acta Crystallographica Section D: Biological Crystallography, D70, 5, 1453-1464 10.1107/S139900471400474X|
|2014||Bell,S, Spence,J, Liu,S, George,J, Wong,L, 2014, Selective aliphatic carbon-hydrogen bond activation of protected alcohol substrates by cytochrome P450 enzymes, Organic and Biomolecular Chemistry, 12, 15, 2479-2488 10.1039/c3ob42417k|
|2013||Vohra,S, Musgaard,M, Bell,S, Wong,L, Zhou,W, Biggin,P, 2013, The dynamics of camphor in the cytochrome P450 CYP101D2, Protein Science, 22, 9, 1218-1229 10.1002/pro.2309|
|2013||Bell,S, French,L, Rees,N, Cheng,S, Preston,G, Wong,L, 2013, A phthalate family oxygenase reductase supports terpene alcohol oxidation by CYP238A1 from Pseudomonas putida KT2440, Biotechnology and Applied Biochemistry, 60, 1, 9-17 10.1002/bab.1084|
|2013||Bell,S, Yang,W, Dale,A, Zhou,W, Wong,L, 2013, Improving the affinity and activity of CYP101D2 for hydrophobic substrates, Applied Microbiology and Biotechnology, 97, 9, 3979-3990 10.1007/s00253-012-4278-7|
|2012||Bell,S, McMillan,J, Yorke,J, Kavanagh,E, Johnson,E, Wong,L, 2012, Tailoring an alien ferredoxin to support native-like P450 monooxygenase activity, Chemical Communications, 48, 95, 11692-11694 10.1039/c2cc35968e|
|2012||Whitehouse,C, Bell,S, Wong,L, 2012, P450BM3 (CYP102A1): connecting the dots, Chemical Society Reviews, 41, 3, 1218-1260 10.1039/C1CS15192D|
|2012||Bell,S, Zhou,R, Yang,W, Tan,A, Gentleman,A, Wong,L, Zhou,W, 2012, Investigation of the substrate range of CYP199A4: modification of the partition between hydroxylation and desaturation activities by substrate and protein engineering, Chemistry-A European Journal, 18, 52, 16677-16688 10.1002/chem.201202776|
|2012||Abdalla,J, Bowen,A, Bell,S, Wong,L, Timmel,C, Harmer,J, 2012, Characterisation of the paramagnetic [2Fe-2S]⁺ centre in palustrisredoxin-B (PuxB) from Rhodopseudomonas palustris, Physical Chemistry Chemical Physics, 14, 18, 6526-6537 10.1039/C2CP24112A|
|2012||Bell,S, Yang,W, Yorke,J, Zhou,W, Wang,H, Harmer,J, Copley,R, Zhang,A, Zhou,R, Bartlam,M et al, 2012, Structure and function of CYP108D1 from Novosphingobium aromaticivorans DSM12444: an aromatic hydrocarbon-binding P450 enzyme, Acta Crystallographica Section D-Biological Crystallography, 68, 3, 277-291 10.1107/S090744491200145X|
|2012||Bell,S, Yang,W, Tan,A, Zhou,R, Johnson,E, Zhang,A, Zhou,W, Rao,Z, Wong,L, 2012, The crystal structures of 4-methoxybenzoate bound CYP199A2 and CYP199A4: structural changes on substrate binding and the identification of an anion binding site, Dalton Transactions (Print Edition), 41, 28, 8703-8714 10.1039/C2DT30783A|
|2011||Ma,M, Bell,S, Yang,W, Hao,Y, Rees,N, Bartlam,M, Zhou,W, Wong,L, Rao,Z, 2011, Structural analysis of CYP101C1 from Novosphingobium aromaticivorans DSM12444, ChemBioChem, 12, 1, 88-99 10.1002/cbic.201000537|
|2011||Zhou,R, Huang,C, Zhang,A, Bell,S, Zhou,W, Wong,L, 2011, Crystallization and Preliminary X-ray analysis of CYP153C1 from Novosphingobium aromaticivorans DSM12444, Acta Crystallographica. Section F: Structural Biology and Crystallization Communications Online, 67, 8, 964-967 10.1107/S174430911102464X|
|2011||Yang,W, Bell,S, Wang,H, Zhou,W, Bartlam,M, Wong,L, Rao,Z, 2011, The structure of CYP101D2 unveils a potential path for substrate entry into the active site, Biochemical Journal, 433, 1, 85-93 10.1042/BJ20101017|
|2011||Rowlatt,B, Yorke,J, Strong,A, Whitehouse,C, Bell,S, Wong,L, 2011, Chain length-dependent cooperativity in fatty acid binding and oxidation by cytochrome P450BM3 (CYP102A1), Protein & Cell, 2, 8, 656-671 10.1007/s13238-011-1082-6|
|2011||Whitehouse,C, Rees,N, Bell,S, Wong,L, 2011, Dearomatisation of xylene by P450BM3 (CYP102A1), Chemistry-A European Journal, 17, 24, 6862-6868 10.1002/chem.201002465|
|2011||Whitehouse,C, Yang,W, Yorke,J, Tufton,H, Ogilvie,L, Bell,S, Zhou,W, Bartlam,M, Rao,Z, Wong,L et al, 2011, Structure, electronic properties and catalytic behaviour of an activity-enhancing CYP102A1 (P450BM3) variant, Dalton Transactions (Print Edition), 40, 40, 10383-10396 10.1039/C1DT10098J|
|2010||Whitehouse,C, Yang,W, Yorke,J, Rowlatt,B, Strong,A, Blanford,C, Bell,S, Bartlam,M, Wong,L, Rao,Z et al, 2010, Structural basis for the properties of two single-site proline mutants of CYP102A1 (P450BM3), ChemBioChem, 11, 18, 2549-2556 10.1002/cbic.201000421|
|2010||Feng,X, Bell,S, Ying,P, Johnson,E, Bartlam,M, Rao,Z, Luet-Lok,W, 2010, Erratum: Crystal structure of a ferredoxin reductase for the CYP199A2 system from Rhodopseudomonas palustris (Proteins: Structure, Function and Bioformatics (2009) 77 (867-880)), Proteins: Structure, Function and Bioinformatics, 78, 2, 501- 10.1002/prot.22627|
|2010||Bell,S, Xu,F, Johnson,E, Forward,I, Bartlam,M, Rao,Z, Wong,L, 2010, Protein recognition in ferredoxin-P450 electron transfer in the class I CYP199A2 system from Rhodopseudomonas palustris, Journal of Biological Inorganic Chemistry, 15, 3, 315-328 10.1007/s00775-009-0604-7|
|2010||Bell,S, Dale,A, Rees,N, Wong,L, 2010, A cytochrome P450 class I electron transfer system from Novosphingobium aromaticivorans, Applied Microbiology and Biotechnology, 86, 1, 163-175 10.1007/s00253-009-2234-y|
|2010||Bell,S, Tan,A, Johnson,E, Wong,L, 2010, Selective oxidative demethylation of veratric acid to vanillic acid by CYP199A4 from Rhodopseudomonas palustris HaA2, Molecular BioSystems, 6, 1, 206-214 10.1039/B913487E|
|2010||Cryle,M, Bell,S, Schlichting,I, 2010, Structural and Biochemical Characterization of the Cytochrome P450 CypX (CYP134A1) from Bacillus subtilis: A Cyclo-l-leucyl-l-leucyl Dipeptide Oxidase, Biochemistry, 49, 34, 7282-7296 10.1021/bi100910y|
|2010||Yang,W, Bell,S, Wang,H, Zhou,W, Hoskins,N, Dale,A, Bartlam,M, Wong,L, Rao,Z, 2010, Molecular characterization of a class I P450 electron transfer system from Novosphingobium aromaticivorans DSM12444, Journal of Biological Chemistry, 285, 35, 27372-27384 10.1074/jbc.M110.118349|
|2009||Holland,J, Giansiracusa,J, Bell,S, Wong,L, Dilworth,J, 2009, In vitro kinetic studies on the mechanism of oxygen-dependent cellular uptake of copper radiopharmaceuticals, Physics in Medicine and Biology, 54, 7, 2103-2119 10.1088/0031-9155/54/7/017|
|2009||Whitehouse,C, Bell,S, Yang,W, Yorke,J, Blanford,C, Strong,A, Morse,E, Bartlam,M, Rao,Z, Wong,L et al, 2009, A highly active single-mutation variant of P450BM3 (CYP102A1), ChemBioChem, 10, 10, 1654-1656 10.1002/cbic.200900279|
|2009||Hong,C, Bell,S, Yang,W, Wang,H, Hao,Y, Li,X, Zhou,W, Bartlam,M, Wong,L, 2009, Purification, crystallization and preliminary X-ray analysis of cytochrome P450 219A1 from Novosphingobium aromaticivorans DSM 12444, Acta Crystallographica. Section F: Structural Biology and Crystallization Communications Online, 65, 4, 364-367 10.1107/S1744309109005648|
|2009||Xu,F, Bell,S, Peng,Y, Johnson,E, Bartlam,M, Rao,Z, Wong,L, 2009, Crystal structure of a ferredoxin reductase for the CYP199A2 system from Rhodopseudomonas palustris, Proteins-Structure Function and Genetics, 77, 4, 867-880 10.1002/prot.22510|
|2009||Bell,S, Vallee,B, 2009, The Metallothionein/Thionein System: an oxidoreductive metabolic zinc link, ChemBioChem, 10, 1, 55-62 10.1002/cbic.200800511|
|2009||Lovett,J, Bowen,A, Timmel,C, Jones,M, Dilworth,J, Caprotti,D, Bell,S, Wong,L, Harmer,J, 2009, Structural information from orientationally selective DEER spectroscopy, Physical Chemistry Chemical Physics, 11, 31, 6840-6848 10.1039/B907010A|
|2008||Whitehouse,C, Bell,S, Wong,L, 2008, Desaturation of alkylbenzenes by Cytochrome P450BM3 (CYP102A1), Chemistry-A European Journal, 14, 35, 10905-10908 10.1002/chem.200801927|
|2008||Bell,S, Xu,F, Forward,I, Bartlam,M, Rao,Z, Wong,L, 2008, Crystal structure of CYP199A2, a para-substituted benzoic acid oxidizing cytochrome P450 from Rhodopseudomonas palustris, Journal of Molecular Biology, 383, 3, 561-574 10.1016/j.jmb.2008.08.033|
|2008||Whitehouse,C, Bell,S, Tufton,H, Kenny,R, Ogilvie,L, Wong,L, 2008, Evolved CYP102A1 (P450BM3) variants oxidise a range of non-natural substrates and offer new selectivity options, Chemical Communications, 28, 8, 966-968 10.1039/B718124H|
|2008||Guo,D, Xu,F, Bell,S, Pang,X, Bartlam,M, Wong,L, 2008, Purification, crystallization and preliminary crystallographic analysis of CYP195A2, a P450 enzyme from Rhodopseudomonas palustris, Protein and Peptide Letters, 15, 4, 423-426 10.2174/092986608784246470|
|2007||Peng,Y, Xu,F, Bell,S, Wong,L, Rao,Z, 2007, Crystallization and preliminary X-ray diffraction studies of a ferredoxin reductase from Rhodopseudomonas palustris CGA009, Acta Crystallographica. Section F: Structural Biology and Crystallization Communications Online, 63, 5, 422-425 10.1107/S1744309107017411|
|2007||Xu,F, Bell,S, Rao,Z, Wong,L, 2007, Structure-activity correlations in pentachlorobenzene oxidation by engineered cytochrome P450cam, Protein Engineering Design and Selection, 20, 10, 473-480 10.1093/protein/gzm028|
|2007||Fleming,B, Bell,S, Wong,LL, Bond,A, 2007, The electrochemistry of a heme-containing enzyme, CYP199A2, adsorbed directly onto a pyrolytic graphite electrode, Journal of Electroanalytical Chemistry, 611, 1-2, 149-154 10.1016/j.jelechem.2007.08.016|
|2007||Pang,X, Xu,F, Bell,S, Guo,D, Wong,L, Rao,Z, 2007, Purification, crystallization and preliminary crystallographic analysis of cytochrome P450 203A1 from Rhodopseudomonas palustris, Acta Crystallographica. Section F: Structural Biology and Crystallization Communications Online, 63, 4, 342-345 10.1107/S1744309107012705|
|2007||Bell,S, Wong,L, 2007, P450 enzymes from the bacterium Novosphingobium aromaticivorans, Biochemical and Biophysical Research Communications, 360, 3, 666-672 10.1016/j.bbrc.2007.06.119|
|2006||Bell,S, Hoskins,N, Xu,F, Caprotti,D, Rao,Z, Wong,L, 2006, Cytochrome P450 enzymes from the metabolically diverse bacterium Rhodopseudomonas palustris, Biochemical and Biophysical Research Communications, 342, 1, 191-196 10.1016/j.bbrc.2006.01.133|
|2005||Xu,F, Bell,S, Lednik,J, Insley,A, Rao,Z, Wong,L, 2005, The heme monooxygenase cytochrome P450(cam) can be engineered to oxidize ethane to ethanol, Angewandte Chemie International Edition, 44, 26, 4029-4032 10.1002/anie.200462630|
|2005||Sowden,R, Yasmin,S, Rees,N, Bell,S, Wong,L, 2005, Biotransformation of the sesquiterpene (+)-valencene by cytochrome P450cam and P450BM-3, Organic and Biomolecular Chemistry, 3, 1, 57-64 10.1039/b413068e|
|2005||Fleming,B, Zhang,J, Bond,A, Bell,S, Wong,L, 2005, Separation of electron-transfer and coupled chemical reaction components of biocatalytic processes using Fourier transform ac voltammetry, Analytical Chemistry, 77, 11, 3502-3510 10.1021/ac048151y|
|2003||Fleming,B, Tian,Y, Bell,S, Wong,L, Urlacher,V, Allen O Hill,H, 2003, Redox properties of cytochrome P450BM3 measured by direct methods, European Journal of Biochemistry, 270, 20, 4082-4088 10.1046/j.1432-1033.2003.03799.x|
|2003||Bentley,E, Astier,Y, Ji,W, Bell,S, Wong,L, Hill,H, 2003, The electrochemistry and scanning tunnelling microscopy of the flavoprotein putidaredoxin reductase on alkanethiol-modified gold, Inorganica Chimica Acta, 356, 343-348 10.1016/S0020-1693(03)00251-2|
|2003||Bell,S, Orton,E, Boyd,H, Stevenson,J, Riddle,A, Campbell,S, Wong,L, 2003, Engineering cytochrome P450cam into an alkane hydroxylase, Dalton Transactions, 11, 2133-2140 10.1039/b300869j|
|2003||Bell,S, Chen,X, Sowden,R, Xu,F, Williams,J, Wong,L, Rao,Z, 2003, Molecular recognition in (+)-α-pinene oxidation by cytochrome P450cam, Journal of the American Chemical Society, 125, 3, 705-714 10.1021/ja028460a|
|2003||Bell,S, Chen,X, Xu,F, Rao,Z, Wong,L, 2003, Engineering substrate recognition in catalysis by cytochrome P450cam, Biochemical Society Transactions, 31, 3, 558-562 10.1042/BST0310558|
|2002||Bell,S, Stevenson,J, Boyd,H, Campbell,S, Riddle,A, Orton,E, Wong,L, 2002, Butane and propane oxidation by engineered cytochrome P450cam, Chemical Communications, 5, 490-491 10.1039/b110957j|
|2002||Chen,X, Christopher,A, Jones,J, Bell,S, Guo,Q, Xu,F, Rao,Z, Wong,L, 2002, Crystal structure of the F87W/Y96F/V247L mutant of cytochrome P-450cam with 1,3,5-trichlorobenzene bound and further protein engineering for the oxidation of pentachlorobenzene and hexachlorobenzene, Journal of Biological Chemistry, 277, 40, 37519-37526 10.1074/jbc.M203762200|
|2001||Bell,S, Harford-Cross,C, Wong,L, 2001, Engineering the CYP101 system for in vivo oxidation of unnatural substrates, Protein Engineering, 14, 10, 797-802 10.1093/protein/14.10.797|
|2001||Bell,S, Sowden,R, Wong,L, 2001, Engineering the haem monooxygenase cytochrome P450cam for monoterpene oxidation, Chemical Communications, 7, 635-636 10.1039/b100290m|
|1997||Bell,S, Rouch,D, Wong,L, 1997, Selective aliphatic and aromatic carbon-hydrogen bond activation catalysed by mutants of cytochrome p450(cam), Journal of Molecular Catalysis - B Enzymatic, 3, 6, 293-302 10.1016/S1381-1177(97)00009-X|
|1996||England,P, Rouch,D, Westlake,A, Bell,S, Nickerson,D, Webberley,M, Flitsch,S, Wong,L, 1996, Aliphatic vs. aromatic C-H bond activation of phenylcyclohexane catalysed by cytochrome P450cam, Chemical Communications, 3, 357-358 10.1039/cc9960000357|
|2007||Bell,S, Hoskins,N, Whitehouse,C, Wong,LL, 2007, Design and engineering of cytochrome P450 systems, Wiley, West Sussex, England, pp. 437-476 10.1002/9780470028155.ch14|
|2007||Urlacher,V, Bell,S, Wong,LL, 2007, The bacterial cytochrome P450 monooxygenases: P450cam and P450BM-3, Wiley, Federal Republic of Germany, pp. 99-122 10.1002/97835276110|
|2010||Wong,LL, Whitehouse,CJ, Yang,W, Yorke,JA, Blanford,CF, Bell,SG, Bartlam,M, Rao,Z, 2010, Engineering P450s by Rational Design, 9th International Meeting of the International-Society-for-the-Study-of-Xenobiotics(ISSX), Istanbul, TURKEY|
|2012||Williamson,NM, Metha,GF, Huang,DM, Bell,SG, 2012, Development of POGIL-Style Organic Chemistry Activities, Australian Conference on Science and Mathematics Education, Sydney|
|2009||Wong,LL, Bell,S, Whitehouse,C; 2009; Mutant Enzymes|
The Australian Research Council are currently funding our research into P450 mechanism through Discovery Project Grants and a Future Fellowship
ARC Discovery Project (2017-2019) DP170103531 Metal-organic Frameworks at the Biointerface (Christian Doonan. Chris Sumby, Stephen Bell, Paolo Falcaro)
This research will yield a detailed understanding of the chemistry that governs the crystallisation of Metal-organic Frameworks around functional biomacromolecules and explore the potential applications of these novel biocomposites. Functional biomacromolecules, such as proteins, show great promise for application to areas of significant commercial and social interest, like biotechnology and Industrial biocatalysis. The research will make significant advances toward the widespread commercial application of biocatalysts and biosensors by developing unique MOF-encapsulated biocatalytic platform materials that will allow inherently fragile biomacromolecules to retain activity in conditions typically required for industrial processes.
My research into isolating and understanding novel P450 electron transfer partners is funded through an ARC Future Fellowship (FT140100355).
ARC Future Fellow, (2014-2018) FT140100355 .
Enzyme catalysed oxidation reactions are key players in the production of naturally occurring biologically active molecules. These processes are tightly regulated by their electron transfer partners. This project will characterise new electron transfer ferredoxin proteins from a metabolically diverse bacterium. The outcomes will advance our understanding of electron transfer, a fundamental process. This will allow strategies to combat human and plant pathogens and unlock the potential of these systems as biocatalysts for the green chemical synthesis of complex and valuable chemicals.
ARC Discovery Project (2014-2016) DP140103229 (James De Voss, Stephen Bell, Mark Bartlam)
Cytochromes P450 are enzymes that play key roles in drug metabolism and biosynthesis. P450s often catalyse hydroxylation but also carry out important transformations such as dehydrogenation or carbon-carbon bond cleavage. Such reactions are pivotal in many biological pathways. This work will elucidate the mechanism of these transformations and the factors that facilitate their occurrence. This will mainly entail the synthesis of small organic mechanistic probes and determining the structure and stereochemistry of the product of enzymic oxidation. Understanding these mechanisms will allow us to predict when such reactions will occur, enabling their utilisation in for example drug design in the avoidance of the formation of toxic metabolites.
I have taught a broad range of courses across all Levels of Chemistry with a focus on Inorganic Chemistry.
Currently whilst on a Future Fellowship I am teaching two level III course
Chem III Inorganic Reaction Mechanisms - with a focus on the reaction kinetics of ligand exchange in metal complexes and how this can be applied to design of metal complexes which can be used in biology and medicine.
Medicinal and Biological Chemistry III - Electron transfer - focus on electron transfer in Chemistry and Biology. Understanding the mechanism, significance and roles of electron transfer in metal-ligand complexes and biological systems. How biological systems have been optimised to regulate electron transfer processes which are critical to life.
My group currently consists of 5 PhD Students and 2 M. Phil Students.
All former students are employed in a variety of sectors including Industry and teaching.
Potential research students are directed to the Adelaide Graduate Centre for information on admissions, applications and scholarship
Questions regarding typical research projects can be directed to Dr Bell.