Primary Reading Epilepsy

Primary Reading Epilepsy

Creators Ota Tamio

Creators Mizuki Akio

Creators Kawasawa Syuhei

Creators Nakamura Yoshitsugu

Creators Yamada Michio

Creators Samura Yukiko

Creators Shibata Jiro

Creators Suizu Kazuo

Phosphorylation of two species of erythrocyte pyruvate kinase (PK, EC 2.7.1.40), PK-R_1 and PK-R_2, was analyzed. The light fraction of younger red cells which has a low PK-R_2/PK-R1 ratio, and the dense fraction of older cells which has a high PK ratio were used as the enzyme source. On phosphorylation in the presence of cyclic AMP, PK of the dense fraction showed a larger amount of ^32P incorporation than that of the light fraction. Most of the radioactivity incorporated was recovered in the L' subunit of PK. The unphosphorylated PK of the dense fraction had a lower affinity for phosphorylated PK of the dense fraction still showed a lower affinity for PEP than that of the light fraction. There results indicate that PK-R_1 and PK-R_2 are controlled by phosphorylation with a decrease of the affinity for PEP. The postsynthetic transformation of PK-R_1 into PK-R_2 is considered as a maturation process or molecular aging of the enzyme which involves protein degradation in erythrocytes.

[ISSN]0513-1812

[NCID]AA00594272