Geometry of the First Step in the Action of Ribonuclease-A

AUTOR(ES)

Usher, D. A.

RESUMO

Advantage was taken of the reversibility of the first step of ribonuclease-A action to synthesize the dinucleoside phosphorothioate Up(S)C from the crystalline isomer of uridine 2′,3′-cyclic phosphorothioate [Up̂(S)] and cytidine. Cyclic phosphorothioate was then reformed from Up(S)C by a nonenzymic reaction known to proceed by an in-line mechanism. The geometry of the enzymic reaction was determined to be in-line by a comparison of the Up̂(S) product with the Up̂(S) originally used. By the principle of microscopic reversibility, the geometry of the first step in the action of ribonuclease-A is shown to be in-line.

Documentos Relacionados

• THE HYDROLYSIS OF URIDINE CYCLIC PHOSPHONATE CATALYZED BY RIBONUCLEASE-A: IMPLICATIONS FOR THE MECHANISM OF ACTION OF THE ENZYME
• BINDING OF HORMONE TO TISSUE: THE FIRST STEP IN POLYPEPTIDE HORMONE ACTION
• The first step in the functional inactivation of the Escherichia coli polynucleotide phosphorylase messenger is a ribonuclease III processing at the 5' end.
• THE MECHANISM OF ACTION OF RIBONUCLEASE
• ON THE MECHANISM OF RIBONUCLEASE ACTION*