Office: SCIE 4244
Lab: SCIE 4201
Our research focuses on the lipopolysaccharide component of the outer membrane of Gram-negative bacteria.
My laboratory is studying pathogenesis of lung infection in cystic fibrosis patients caused by Pseudomonas aeruginosa. The specific focuses are to understand the molecular biology of the biosynthesis of lipopolysaccharide (LPS) in the bacterium, Pseudomonas aeruginosa, the role of LPS in pathogenesis, and to investigate the use of glycoconjugates and enzymes in the LPS metabolic pathways as "targets" for developing new antimicrobials to control P. aeruginosa infections. We use cutting-edge technology and develop new methods to deal with genes and their encoded protein products associated with LPS synthesis and regulations. We routinely over-express these proteins using pET, pBAD and other systems; and purify them using FPLC. This allows us to perform various studies including mass spectrometry, x-ray crystallography, kinetics of interactions among various proteins, and importantly, development of assays that can be used for high-throughput drug screening (this last aspect is very costly and is done through a collaboration with a pharmaceutical company). My laboratory is well equipped with modern research instrumentation including a capillary electrophoresis (CE), a biosensor apparatus, BIACORE, and a FPLC/HPLC instrument for protein purification. Research in my laboratory provides a broad-based training for postdoctoral fellows, graduate students, and senior undergraduate project students in microbiology, molecular biology and biochemistry.
Ishiyama, N, M. Demendi, C. Creuzenet, G. Harauz, J. S. Lam, and A.M. Berghuis. 2006. Structural studies of FlaA1, from Helicobacter pylori reveal the mechanism for inverting 4, 6 dehydratase activity. J. Biol. Chem. 281:24489-24495
Wenzel, C.Q. , C. Daniels, R.A.B. Keates, D. Brewer, and J.S. Lam. 2005. Evidence that WbpD is an N-acetyltransferase belonging to the hexapeptide acyltransferase superfamily and an important protein for O-antigen biosynthesis in Pseudomonas aeruginosa PAO1. Mol. Microbiol. 57:1288-1303.
Sriramulu, D.D, H. Lünsdorf, J.S Lam, and U. Römling. 2005. Microcolony formation: a novel biofilm model of Pseudomonas aeruginosa for the cystic fibrosis lung. J. Med. Microbiol. 54:667-676.
Mulrooney, E.F., K.K.H. Poon, D.J. McNally, J.-R. Brisson, and J.S. Lam. 2005. Biosynthesis of UDP-N-acetyl-L-fucosamine, a precursor to the biosynthesis of lipopolysaccharide in Pseudomonas aeruginosa serotype O11. J. Biol. Chem. 280:19535-19542 (Epub ahead of print, Mar 18, 2005).
Demendi, M., N. Ishiyama, J.S. Lam, A.M. Berghuis, and C. Creuzenet. 2005. Towards a better understanding of the substrate specificity of the UDP-GlcNAc C4 epimerase WbpP. Biochem J. 389:173-180 [Epub ahead of print, Mar 8]
Priyanka D. Abeyrathne, Craig Daniels , Karen. K. H. Poon, Mauricia J. Matewish, and Joseph S. Lam. 2005. Functional characterization of WaaL, a ligase associated with linking O-antigen polysaccharide to the core of Pseudomonas aeruginosa lipopolysaccharide. see paper J. Bacteriol. 187:3002-3012.
Miller, W.L., C.Q. Wenzel, C. Daniels, S. Larocque, J.R. Brisson, and J.S. Lam. 2004. Biochemical characterization of WbpA, a UDP-N-acetyl-D-glucosamine 6-dehydrogenase involved in O-antigen biosynthesis in Pseudomonas aeruginosa PAO1. J. Biol. Chem. 279:37551-37558.
Ishiyama, N., C. Creuzenet, J.S. Lam, and A.M. Berghuis. 2004. Crystal structure of WbpP, a genuine UDP-N-acetylglucosamine 4-epimerase from Pseudomonas aeruginosa: Substrate specificity in UDP-Hexose 4-epimerases. J. Biol. Chem. 279:22635-22642.
Webb, N.A., A.M. Mulichak, J.S. Lam, H.L. Rocchetta, and R.M. Garavito. 2004. Crystal structure of a tetrameric GDP-D-mannose 4,6-dehydratase from a bacterial GDP-D-rhamnose biosynthetic pathway. Protein Science 13:529-539.
Antoine, T., B. Priem, A. Heyraud, L. Greffe, M. Gilbert, W.W. Wakarchuk, J.S. Lam, and E. Samain. 2003. Large-scale in vivo synthesis of the carbohydrate moieties of gangliosides GM1 and GM2 by metabolically engineered Escherichia coli. Chembiochem. 4:406-412.
Kneidinger, B., S. Larocque, J.R. Brisson, N. Cadotte, and J.S. Lam. 2003. Biosynthesis of 2-acetamido-2,6-dideoxy-L-hexoses in bacteria follows a pattern distinct from those of the pathways of 6-deoxy-L-hexoses. Biochem. J. 371:989-995.
Kneidinger B., K. O’Riordan, J. Li, J.R. Brisson, J.C. Lee, and J.S. Lam. 2003. Three highly conserved proteins catalyze the conversion of UDP-N-acetyl-D-glucosamine to precursors for the biosynthesis of O antigen in Pseudomonas aeruginosa O11 and capsule in Staphylococcus aureus type 5 implications for the UDP-N-acetyl-L-fucosamine biosynthesis pathway. J. Biol. Chem. 278:3615-3627.
Daniels, C., C. Griffiths, B. Cowles, and J.S. Lam. 2002. Pseudomonas aeruginosa O-antigen chain length is determined prior to ligation to lipid A core. Environ. Microbiol. 4:883-897.
Digiandomenico, A., M. J. Matewish, A. Bisaillon, J.R. Stehle, J.S. Lam, and P. Castric. 2002. Glycosylation of Pseudomonas aeruginosa 1244 pilin: Specificity of glycan substrate. Mol. Microbiol. 46:519-530.
Creuzenet C., R.V. Urbanic, and J.S. Lam. 2002. Structure-function studies of two novel UDP-GlcNAc C6 dehydratases /C4 reductases: Variation from the SYK dogma. J. Biol. Chem. 277:26769-26778.
Zhao, X., C.Q. Wenzel, and J.S. Lam. 2002. Development of a non-radiolabelling assay of WaaP, a novel sugar kinase, essential for the biosynthesis of core lipopolysaccharide of Pseudomonas aeruginosa. Antimicrob. Agents Chemother. 46:2035-2037.
Zhao X., and J.S. Lam. 2002. WaaP of Pseudomonas aeruginosa is a novel eukaryotic type protein-tyrosine kinase as well as a sugar kinase essential for the biosynthesis of core lipopolysaccharide. J. Biol. Chem. 277:4722-30.
Creuzenet C., and J.S. Lam. 2001. Topological and functional characterization of WbpM, an inner membrane UDP-GlcNAc C6 dehydratase essential for lipopolysaccharide biosynthesis in Pseudomonas aeruginosa. Mol. Microbiol. 41:1295-1310.
Vinogradov, E., E.E. Egbosimba, M.B. Perry, J.S. Lam, and C.W. Forsberg. 2001. Structural analysis of the carbohydrate components of the outer membrane of the lipopolysaccharide-lacking cellulolytic ruminal bacterium Fibrobacter succinogenes S85. Eur. J. Biochem. 268:3566-3576.
Rahim, R., C. Olvera, M. Graninger, P. Messner, U.A. Ochsner, J.S. Lam* and G. Soberón-Chávez. 2001. Cloning and functional characterization of the Pseudomonas aeruginosa rhlC gene that encodes rhamnosyltransferase 2, an enzyme responsible for di-rhamnolipid biosynthesis. Mol. Microbiol. 40:708-718.
Newton, G.J., C. Daniels, L.L. Burrows, A.M. Kropinski, A.J. Clarke, and J.S.Lam. 2001. Three-component-mediated serotype conversion in Pseudomonas aeruginosa. Mol. Microbiol. 39:1237-1247.
Blankenfeldt, W., M. Asuncion, J.S. Lam, and J.H. Naismith. 2000. The structural basis of the catalytic mechanism and regulation of glucose-1-phosphate thymidylyltransferase (RmlA). EMBO J. 19:6652-6663.
Blankenfeldt, W. M-F. Giraud, G. Leonard, R. Rahim, C. Creuzenet, J.S. Lam, and J.H. Naismith. 2000. The purification, crystallisation and preliminary structureal characterisation of glucose-1-phosphate thymidlyltransferase (RmlA), the first enzyme of the dTDP-L-rhamnose synthesis pathway from Pseudomonas aeruginosa. ACTA Cryst. Sect. D 56:1501-1504.
Creuzenet, C., M. Belanger, X. Li, W. Wakarchuk, and J.S. Lam. 2000. Expression, purification, and biochemical characterization of WbpP, a new UDP-GlcNAc C4 epimerase from Pseudomonas aeruginosa serotype O6. J. Biol. Chem. 275:19060-19067.
Creuzenet, C., M. Schur, J. Li, W.W. Wakarchuk, and J.S. Lam. 2000. FlaA1, a new bifunctional UDP-GlcNAc C6 dehydratase / C4 reductase from Helicobacter pylori. J. Biol. Chem. 275:34873-34880
Zhao, X. C. Creuzenet, M. Belanger, E. Egbosimba, J. Li, and J.S. Lam. 2000. WbpO, a UDP-N-acetyl-D-galactosamine dehydrogenase from Pseudomonas aeruginosa serotype O6. J. Biol. Chem. 275:33252-33259.
Walsh, A.G., M.J. Matewish, L.L. Burrows, M.A. Monteiro, M.B. Perry, and J.S. Lam. 2000. Lipopolysaccharide core phosphates are required for viability and intrinsic drug resistance in Pseudomonas aeruginosa. Mol. Microbiol. 35:718-727.
Burrows, L.L., R.V. Urbanic, and J.S. Lam. 2000. Functional conservation of the polysaccharide biosynthetic protein WbpM and its homologues in P. aeruginosa and other medically significant bacteria. Infect. Immun. 68:931-936.
Yang H., M. Matewish, I. Loubens, D. Storey, J.S. Lam, and S. Jin. 2000. MigA, a quorum reponsive gene of Pseudomonas aeruginosa is highly expressed in cystic fibrosis lung environment and modifies low-molecular-weight lipopolysaccharide. Microbiology 146:2509-2519.
Rahim, R., L.L. Burrows, M.A. Monteiro and M.B. Perry and J.S. Lam. 2000. Involvement of the rml locus in core oligosaccharide and O polysaccharide assembly in Pseudomonas aeruginosa. Microbiology 146:2803-2814
Burrows, L.L., K.E. Pigeon, and J.S. Lam. 2000. Pseudomonas aeruginosa B-band lipopolysaccharide genes wbpA and wbpI and their Escherichia coli homologues wecC and wecB are not functionally interchangeable. FEMS Microbiol. Lett. 189:135-141.
Sadovskaya, I., J.-R. Brisson, P. Thibault, J.C. Richards, J.S. Lam, and E. Altman. 2000. Structural characterization of the outer core and the O-chain linkage region of lipopolysaccharide from Pseudomonas aeruginosa serotype O5. Eur. J. Biochem. 267:1640-1650.
Ghanei, Hamed (M.Sc.)
Kaluzny, Kasia (M.Sc.)
Miller, Wayne L. (Ph.D.)
Mulrooney, Erin "Emmy" (M.Sc.)
To, Terence (M.Sc.)
Westman, Erin "Louise" (M.Sc.)