PURIFICATION, CRYSTALLISATION AND PRELIMINARY X-RAY ANALYSIS OF PENICILLIN BINDING PROTEIN 4 FROM ESCHERICHIA COLI, A PROTEIN RELATED TO CLASS A BETA-LACTAMASES

摘要

Crystals of the penicillin binding protein 4 (PBP4) from Escherichia coli have been obtained at 37 degrees C from liquid to liquid diffusion experiments in capillaries. PBP4 was dissolved in a 1.0 M ammonium sulphate solution, buffered at pH 7.2, to a concentration of 5 mg/ml, and was layered on top of a 1.6 to 2.2 M ammonium sulphate solution. Crystals appeared within four to six weeks. They belong to space group C222 with cell dimensions a = 68.5 Angstrom, b = 100.5 Angstrom and c = 137.0 Angstrom, and diffract to at least 2.8 Angstrom resolution. There is one molecule with a molecule mass of 49,568 Da in the asymmetric unit. [References: 44]