NOT KNOWN FACTUAL STATEMENTS ABOUT PKRRATING

3B). R526 from your loop in between αJ and αI anchors the C-terminal percentage of the activation loop by forming a salt bridge with E458 at the base of αEF. Q459 stabilizes the HRD motif by a hydrogen bond to the main chain carbonyl of R413. The tip of the activation section is stabilized by a hydrogen bond involving Y454 and E480 from αfile.