Crystallization and preliminary X-ray diffraction analysis of proximal thread matrix protein 1 (PTMP1) from Mytilus galloprovincialis

In order to deal with the dynamic ocean environment, blue mussels adhere to various surfaces via their collagenous byssal threads. PTMP1 (proximal thread matrix protein 1) is one identified matrix protein residing in the proximal thread and is capable of collagen binding. Its sequence comprises two von Willebrand factor type A-like repeats. In order to characterize the structure and domain architecture of PTMP1, recombinant protein was crystallized by vapour diffusion. The obtained crystals diffracted to 1.95 angstrom resolution and belonged to space group P2(1), with unit-cell parameters a = 62.0, b = 62.3, c = 122.6 angstrom, beta = 102.2 degrees. The Matthews coefficient suggested the presence of two monomers in the asymmetric unit and 48.3% solvent content.