3B). R526 with the loop in between ?J and ?I anchors the C-terminal portion of the activation loop by forming a salt bridge with E458 at the base of ?EF. Q459 stabilizes the HRD motif by a hydrogen bond to the main chain carbonyl of R413. The tip from the activation segment is stabilized by a hydrogen bond between Y454 and E480 from ?F. within the … Read More