Transformations moleculaires au niveau des isozymes de la lacticodehydrogenase de la souris, mises en evidence par electrophorese en gel d'amidon

Intra- and inter-isozymic molecular relationships of mouse lactate dehydrogenase (EC 1.1.1.27) have been studied using starch-gel electrophoresis.

• 1.

  1. Each isozyme (LDH 2 to LDH ₅) exhibits several narrow bands (sub-bands). These sub-bands present sequential and reversible molecular transformations inside the corresponding isozymic region of migration.

• 2.

  2. Several physicochemical factors, in vitro, determine the direction of these molecular transformations.

• 3.

  3. There are, in cells and tissues, definite specific properties, which are depending on the type of cellular differentiation, and which modify the behavior of the intra-isozymic sub-bands.

• 4.

  4. The enzymatic form migrating towards the cathode (cathodic band) may release, under certain conditions, the isozymes LDH₅, LDH₄, LDH₃. This enzymatic form would appear to be an aggregation between isozymes. There is a relationship between cathodic band formation and the intra-isozymic sub-band transformations.

A hypothesis according to which different molecular conformations of lactate dehydrogenase would account for these results, to a first approximation, is discussed.