... Met1 21, Ile 118 , Leu122 and Phe 114 , which arelocated at the end of t his helix. Conformational changes inthese residues would then change the affinity for CDNBbinding, which is supported by the ... prevents the reaction of the Met1 21 of the s econdsubunit. The biphasic kinetics observed may be explainedby assuming that the two subunits, o r at least the conformation of the Met1 21 side chains ... S-transferase (GST; EC 2.5. 1. 18).(Received 20 April 2004, r evised 8 July 2004, accepted 12 July 2004)Eur. J. Biochem. 2 71, 3503–3 511 (2004) Ó FEBS 2004 doi :10 .11 11/ j .14 32 -10 33.2004.04285.xdeveloping...