Abstact

The crystal structure of a complex of the catalytic subunit (type alpha) of cAMP-dependent protein kinase (PKA C alpha) with ARC-type inhibitor (ARC-1034), the presumed lead scaffold of previously reported adenosine-oligo-arginine conjugate-based (ARC-type) inhibitors, was solved. Structural elements important for interaction with the kinase were established with specifically modified derivatives of the lead compound. On the basis of this knowledge, a new generation of inhibitors, conjugates of adenosine-4'-dehydroxymethyl-4'-carboxylic acid moiety and oligo(D-arginine), was developed with inhibitory constants well into the subnanomolar range. The structural determinants of selectivity of the new compounds were established in assays with ROCK-II and PKBgamma.