Crystallization and preliminary X-ray studies on human epidermal growth factor.

Single crystals of human epidermal growth factor have been prepared from a polyethylene glycol solution and characterized by X-ray diffraction. The crystals grow in a space group of P2(1) with unit cell dimensions of a = 32.7, b = 32.5, c = 22.3 A, and beta = 96.9 degrees. They contain a single molecule per asymmetric unit and show better diffraction than 2.5 A.