Yeast phosphofructokinase exists in several enzymically active, interconvertible forms with molecular weights of 180,000, 370,000, 570,000 and 750,000. With disc-electrophoresis catalytically active aggregation products with molecular weights of more than one million can be detected.In alkaline media fragmentation of phosphofructokinase occurs, leading to a variety of catalytically inactive products. These seem to be oligomers of subunits with 60,000 daltons. A model of the complex subunit structure of yeast phosphofructokinase is suggested. The various catalytically active forms of the enzyme are considered as polymers of 180,000 monomers, which themselves are enzymatically active and which are composed of three 60,000 subunits.
Liebe
S
S
Physiologisch-chemisches Institut der Karl-Marx-Universität, Leipzig, DDR
Kopperschläger
G
G
Diezel
W
W
Nissler
K
K
Wolff
J
J
Hofmann
E
E