Crystallization and preliminary X-ray diffraction studies of NP24-I, an isoform of a thaumatin-like protein from ripe tomato fruits.

NP24 is a 24 kDa (207-amino-acid) antifungal thaumatin-like protein (TLP) found in tomato fruits. An isoform of the protein, NP24-I, is reported to play a possible role in ripening of the fruit in addition to its antifungal properties. The protein has been isolated and purified and crystallized by the hanging-drop vapour-diffusion method. The crystals belong to the tetragonal space group P4(3), with unit-cell parameters a = b = 61.01, c = 62.90 A and one molecule per asymmetric unit. X-ray diffraction data were processed to a resolution of 2.45 A and the structure was solved by molecular replacement.