Edward J Meehan

Publications (8) View all

• Article: Structural basis of transport of lysophospholipids by human serum albumin.

  Shihui Guo, Xiaoli Shi, Feng Yang, Liqing Chen, Edward J Meehan, Chuanbing Bian, Mingdong Huang
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  ABSTRACT: Lysophospholipids play important roles in cellular signal transduction and are implicated in many biological processes, including tumorigenesis, angiogenesis, immunity, atherosclerosis, arteriosclerosis, cancer and neuronal survival. The intracellular transport of lysophospholipids is through FA (fatty acid)-binding protein. Lysophospholipids are also found in the extracellular space. However, the transport mechanism of lysophospholipids in the extracellular space is unknown. HSA (human serum albumin) is the most abundant carrier protein in blood plasma and plays an important role in determining the absorption, distribution, metabolism and excretion of drugs. In the present study, LPE (lysophosphatidylethanolamine) was used as the ligand to analyse the interaction of lysophospholipids with HSA by fluorescence quenching and crystallography. Fluorescence measurement showed that LPE binds to HSA with a Kd (dissociation constant) of 5.6 microM. The presence of FA (myristate) decreases this binding affinity (Kd of 12.9 microM). Moreover, we determined the crystal structure of HSA in complex with both myristate and LPE and showed that LPE binds at Sudlow site I located in subdomain IIA. LPE occupies two of the three subsites in Sudlow site I, with the LPE acyl chain occupying the hydrophobic bottom of Sudlow site I and the polar head group located at Sudlow site I entrance region pointing to the solvent. This orientation of LPE in HSA suggests that HSA is capable of accommodating other lysophospholipids and phospholipids. The study provides structural information on HSA-lysophospholipid interaction and may facilitate our understanding of the transport and distribution of lysophospholipids.
  Biochemical Journal 08/2009; 423(1):23-30. · 4.90 Impact Factor
• Article: Cloning, expression, crystallization and preliminary X-ray analysis of the DNA-binding protein Sso10a from Sulfolobus solfataricus.

  M J Teale, M Kahsai, S K Singh, S P Edmondson, R Gupta, J W Shriver, E Meehan
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  ABSTRACT: The gene for the DNA-binding protein Sso10a from the hyperthermophilic archaeon Sulfolobus solfataricus was cloned and overexpressed in Escherichia coli. Crystals of the purified protein have been grown that diffract to beyond 2.15 A resolution. The protein crystals belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 57.24, b = 60.16, c = 69.96 A. With one dimer per asymmetric unit, the crystal to volume per protein mass (V(M)) is 2.9 A(3) Da(-1) and the solvent content is approximately 57%. Complete X-ray diffraction native data were collected from a single crystal and processed to 2.15 A.
  Acta Crystallographica Section D Biological Crystallography 08/2003; 59(Pt 7):1320-2. · 12.62 Impact Factor
• Article: Synthesis and characterization of a novel betaine dye: 2,4-dimethyl-6-(2,4,6-triphenyl-N-pyridinio)phenolate

  M. S. Paley, E. J. Meehan, C. D. Smith, F. E. Rosenberger, S. C. Howard, J. M. Harris
  04/2002;
• Article: Crystallization and preliminary X-ray diffraction analysis of restriction endonuclease EcoRII.

  E A Karpova, E Meehan, M L Pusey, L Chen
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  ABSTRACT: Crystals of the restriction endonuclease EcoRII have been obtained by the vapor-diffusion technique in the presence of ammonium sulfate or polyethylene glycol. The best crystals were grown with ammonium sulfate as a precipitant. Crystals with dimensions of up to 0.6 x 0. 6 x 0.6 mm have been observed. The crystals diffract to about 4.0 A resolution at a cryo-temperature of 100 K using a rotating-anode X-ray source and a Rigaku R-AXIS IV imaging-plate detector. The space group has been determined to be either I23 or I2(1)3, with unit-cell parameters a = b = c = 160.3 A, alpha = beta = gamma = 90 degrees. The crystal asymmetric unit contains two protein molecules, and self-rotation function analysis shows a pseudo-twofold symmetry relating the two monomers. Attempts to improve the resolution of crystal diffraction and to search for heavy-atom derivatives are under way.
  Acta Crystallographica Section D Biological Crystallography 10/1999; 55(Pt 9):1604-5. · 12.62 Impact Factor
• Article: Structural genomics of Caenorhabditis elegans: crystal structure of the tropomodulin C-terminal domain.

  Shanyun Lu, Jindrich Symersky, Songlin Li, Mike Carson, Liqing Chen, Edward Meehan, Ming Luo
  Proteins Structure Function and Bioinformatics 09/2004; 56(2):384-6. · 3.39 Impact Factor