A new topology of ACBP from Moniliophthora perniciosa

作者：Monzani Paulo S; Pereira Humberto M; Melo Fernando A; Meirelles Flavio V; Oliva Glaucius; Cascardo Julio C M^*

来源：Biochimica et Biophysica Acta-Proteins and Proteomics, 2010, 1804(1): 115-123.

DOI：10.1016/j.bbapap.2009.09.020

• ACBP
• Characterization
• Crystal structure
• Four-helix bundle
• Moniliophthora perniciosa and Witches' broom disease

Acyl-CoA binding protein (ACBP) is a housekeeping protein and is an essential protein in human cell lines and in Trypanosoma brucei. The ACBP of Moniliophthora perniciosa is composed of 104 amino acids and is possibly a non-classic isoform exclusively from Basidiomycetes. The M. perniciosa acbp gene was cloned, and the protein was expressed and purified. Acyl-CoA ester binding was analyzed by isoelectric focusing, native gel electrophoresis and isothermal titration calorimetry. Our results suggest an increasing affinity of ACBP for longer acyl-CoA esters, such as myristoyl-CoA to arachidoyl-CoA, and best fit modeling indicates two binding sites. ACBP undergoes a shift from a monomeric to a dimeric state, as shown by dynamic light scattering, fluorescence anisotropy and native gel electrophoresis in the absence and presence of the ligand. The protein's structure was determined at 1.6 angstrom resolution and revealed a new topology for ACBP, containing five a-helices instead of four. alpha-helices 1, 2, 3 and 4 adopted a bundled arrangement that is unique from the previously determined four-helix folds of ACBP, while alpha-helices 1, 2, 4 and 5 formed a classical four-helix bundle. A MES molecule was found in the CoA binding site, suggesting that the CoA site could be a target for small compound screening.

• 出版日期2010-1