Cloning, purification, crystallization and preliminary X-ray crystallographic analysis of MCAT from Staphylococcus aureus

Malonyl-CoA:acyl-carrier protein transacylase (MCAT; FabD) from S. aureus has been cloned, overexpressed, purified and crystallized. The crystal belonged to space group P2₁, with unit-cell parameters a = 41.608, b = 86.717, c = 43.163 Å, α = γ = 90, β = 106.330°, and data were collected to 1.2 Å resolution using synchrotron radiation. Malonyl-CoA:acyl-carrier protein transacylase (MCAT), encoded by the fabd gene, is a key enzyme in type II fatty-acid biosynthesis. It is responsible for transferring the malonyl group from malonyl-CoA to the holo acyl-carrier protein (ACP). Since the type II system differs from the type I system that mammals use, it has received enormous attention as a possible antibiotic target. In particular, only a single isoform of MCAT has been reported and a continuous coupled enzyme assay has been developed. MCAT from Staphylococcus aureus was overexpressed in Escherichia coli and the protein was purified and crystallized. Diffraction data were collected to 1.2 Å resolution. The crystals belonged to space group P2₁, with unit-cell parameters a = 41.608, b = 86.717, c = 43.163 Å, α = γ = 90, β = 106.330°. The asymmetric unit contains one SaMCAT molecule