for his work on ribonucleaseandfor their contribution to the understanding of the connection between chemical structure and catalytic activity of the ribonuclease molecule
for their elucidation of the enzymatic mechanism underlying the synthesis of adenosine triphosphateandfor his discovery of an ion-transporting enzyme, Na+, K+ -ATPase
... "caturtitatpurusha" is a karmadhariya, being both dative, and a tatpurusha.
The verbs tenses (a very inexact application of the word, since more distinctions than ...