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
... Stiva's friend Levin has returned Moscow from his country estate with the intention of proposing to Kitty. He first meets Stiva who encourages him in this plan, but, later ...