Abstract
The extracellular signal-regulated kinase ERK2, a member of the protein kinase superfamily, phosphorylates a variety of cellular proteins in response to extracellular signals. ERK2 expressed in
Escherichia coli as a fusion protein with the sequence Ala-His
6 at the N terminus has low basal activity and very low levels of phosphate incorporation, but can be fully activated. The Ala-His
6 ERK2 as expressed in the unphosphorylated form has been crystallized in space group
P2
1. The cell constants are
a = 49·32 Å,
b = 71·42 Å,
c = 61·25 Å, and β = 109·75°, and the crystals diffract to better than 1·8 Å resolution.
