The M2 and M1-PK isoenzymes are encoded by the same gene but result from alternative splicing of exons 9 and 10. The human M2 and M1-PK isoenzyme differ in 23 amino acids within a stretch of 56 amino acids.
Amino acid sequence of human pyruvate kinase type M2
56 amino acids (379 - 435) differing between M1 and M2-PK |
|
underlined |
phosphorylation sites: tyrosine (390); threonine (405), serine (406) |
Fructose 1,6-P2 binding |
Lys 433, Ser 434, Ser 437, Gly 520 (6´-phoshate oxygen) |
underlined |
HERC1-interacting region (407-531) |
active site (Lys 270, Lys 367) |