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Three Pyruvate Kinase Variants with Increased Affinity for PEP
Author(s) -
Elder G. Elizabeth,
Lappin T. R. J.,
Lawson Barbara E.,
Bridges J. M.
Publication year - 1981
Publication title -
british journal of haematology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.907
H-Index - 186
eISSN - 1365-2141
pISSN - 0007-1048
DOI - 10.1111/j.1365-2141.1981.tb02804.x
Subject(s) - pyruvate kinase , allosteric regulation , thermostability , enzyme , mutant , chemistry , biochemistry , microbiology and biotechnology , biology , glycolysis , gene
S ummary . Three variants of pyruvate kinase are described which have marked reduction of activity associated with severe non‐spherocytic haemolytic anaemia. Each variant shows a reduced K 0.5 PEP (the value of the intercept of the abscissa on the Hill plot) and reduced Hill coefficient; FDP activation and ATP inhibition are less than normal and utilization of GDP is increased. The variants are slightly less inhibited by 2,3DPG than controls but require more FDP to relieve this inhibition. Cases 1 and 2 have decreased thermostability but case 3 is normal. The mutant enzymes are further distinguished by their affinity for FDP. Their kinetic and physicochemical properties are compared with other known cases with high affinity for PEP and discussed in terms of a RT model for allosteric enzymes.