TY - JOUR
T1 - Insights into the phosphoryl transfer catalyzed by cAMP-dependent protein kinase
T2 - An X-ray crystallographic study of complexes with various metals and peptide substrate SP20
AU - Gerlits, Oksana
AU - Waltman, Mary Jo
AU - Taylor, Susan
AU - Langan, Paul
AU - Kovalevsky, Andrey
PY - 2013/5/28
Y1 - 2013/5/28
N2 - X-ray structures of several ternary substrate and product complexes of the catalytic subunit of cAMP-dependent protein kinase (PKAc) have been determined with different bound metal ions. In the PKAc complexes, Mg2+, Ca 2+, Sr2+, and Ba2+ metal ions could bind to the active site and facilitate the phosphoryl transfer reaction. ATP and a substrate peptide (SP20) were modified, and the reaction products ADP and the phosphorylated peptide were found trapped in the enzyme active site. Finally, we determined the structure of a pseudo-Michaelis complex containing Mg 2+, nonhydrolyzable AMP-PCP (β,γ-methyleneadenosine 5′-triphosphate) and SP20. The product structures together with the pseudo-Michaelis complex provide snapshots of different stages of the phosphorylation reaction. Comparison of these structures reveals conformational, coordination, and hydrogen bonding changes that might occur during the reaction and shed new light on its mechanism, roles of metals, and active site residues.
AB - X-ray structures of several ternary substrate and product complexes of the catalytic subunit of cAMP-dependent protein kinase (PKAc) have been determined with different bound metal ions. In the PKAc complexes, Mg2+, Ca 2+, Sr2+, and Ba2+ metal ions could bind to the active site and facilitate the phosphoryl transfer reaction. ATP and a substrate peptide (SP20) were modified, and the reaction products ADP and the phosphorylated peptide were found trapped in the enzyme active site. Finally, we determined the structure of a pseudo-Michaelis complex containing Mg 2+, nonhydrolyzable AMP-PCP (β,γ-methyleneadenosine 5′-triphosphate) and SP20. The product structures together with the pseudo-Michaelis complex provide snapshots of different stages of the phosphorylation reaction. Comparison of these structures reveals conformational, coordination, and hydrogen bonding changes that might occur during the reaction and shed new light on its mechanism, roles of metals, and active site residues.
UR - http://www.scopus.com/inward/record.url?scp=84878329652&partnerID=8YFLogxK
U2 - 10.1021/bi400066a
DO - 10.1021/bi400066a
M3 - Article
C2 - 23672593
AN - SCOPUS:84878329652
SN - 0006-2960
VL - 52
SP - 3721
EP - 3727
JO - Biochemistry
JF - Biochemistry
IS - 21
ER -