Description_x000D_ General description_x000D_ Human EPHB4 ( GenBank Accession No. NM_004444), amino acids 563-987 with N-terminal His tag, MW=50 kDa, expressed in a Baculovirus infected Sf9 cell expression system._x000D_ Application_x000D_ Useful for the study of enzyme kinetics, screening inhibitors, and selectivity profiling._x000D_ Unit Definition_x000D_ One unit is defined as the amount of enzyme that will transfer 1 nmol phosphate to tyrosine substrate per minute at pH 7.4 and 30° C.