crystallization communications
asHPAL, a member of the HpaI/HpcH subfamily of class II aldolases, was expressed, purified and crystallized in the absence and presence of 2-ketobutyrate as one of its substrates using the sitting-drop vapour-diffusion method. asHPAL crystals grown without and with 2-ketobutyrate diffracted to 1.60 and 1.55 Å resolution, respectively.