Open AccessAffinity labelling of the allosteric site of the L ‐lactate dehydrogenase of Lactobacillus casei
Author(s) -
HENSEL Reinhard,
MAYR Ulrich,
WOENCKHAUS Christoph
Publication year - 1983
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1983.tb07662.x
Subject(s) - allosteric regulation , allosteric enzyme , lactobacillus casei , biochemistry , chemistry , binding site , histidine , substrate (aquarium) , enzyme , biology , ecology , fermentation
Kinetic investigations employing the substrate analogues 2‐oxoglutarate and phospho( enol )pyruvate indicate that the allosteric L ‐lactate dehydrogenase (EC 1.1.1.27) of Lactobacillus casei has a non‐catalytic pyruvate‐binding site to which, in addition to pyruvate, the allosteric effector fructose 1,6‐bisphosphate can also be bound. A modification using the 14 C‐labelled substrate analogue 3‐bromopyruvate induces a loss of regulation by fructose 1,6‐bisphosphate. The histidine residue labelled by 3‐bromopyruvate is homologous to histidine‐188 which is part of the anion‐binding site of the non‐allosteric vertebrate l ‐lactate dehydrogenases. Thus, the allosteric site of the allosteric l ‐lactate dehydrogenases corresponds to the anion‐binding site of the non‐allosteric vertebrate enzymes.