The dual activity of pyruvate kinase type M2 from chromatin extracts of neoplastic cells.

Pyruvate kinase type M(2) from Morris hepatoma 7777 tumour cell nuclei and cytosol, in contrast to types L and M(2) from nuclei and cytosol of normal rat liver, shows the histone H(1) kinase activity. Moreover, in the presence of L-cysteine and without ADP it converts 2-phosphoenolpyruvate (PEP) to pyruvate while in the presence of L-arginine or L-histidine does not. L-Cysteine markedly stimulates the activity of histone H(1) kinase transferring a phosphate group from PEP to, as results suggested, the epsilon -amino group of L-lysine of histone H(1).

The effect of chitosan on stiffness and glycolytic activity of human bladder cells.

The cell's cytoskeleton together with the cell membrane and numerous accessory proteins determines the mechanical properties of cell. Any factors influencing cell organization and structure can cause alterations in mechanical properties of cell (its ability for deformation and adhesion). The determination of the local elastic properties of cells in their culture conditions has opened the possibility for the measurement of the influence of different factors on the mechanical properties of the living cells.

Amino-acid composition of pyruvate kinase M2 isoenzyme variants from rat liver and Morris hepatoma 7777.

Cytosolic fractions B (salted out between 51-70% ammonium sulphate saturation) from rat liver and Morris hepatoma 7777, containing pyruvate kinase (EC 2.7.1.

Tumor-specific pyruvate kinase isoenzyme M2 involved in biochemical strategy of energy generation in neoplastic cells.

The differences in properties of pyruvate kinase (EC 2.1.7.

N-acetylneuraminic acid, phosphate and thiol groups of pyruvate kinase isoenzymes from Morris hepatoma 7777 and normal rat liver.

The highest amount of N-acetylneuraminic acid (AcNeu) was found in pyruvate kinase isoenzyme L from normal rat liver (24 moles/mole of enzyme tetramer), with the highest electrophoretic mobility. On the other hand, isoenzyme M2 from Morris hepatoma 7777, with the lowest electrophoretic mobility, had the lowest AcNeu content (5 moles/mole of enzyme tetramer). This tumour isoenzyme M2 of pyruvate kinase was, however, characterised by the highest phosphate content (12 moles/mole protein), in comparison to isoenzyme L (3 moles/mole protein) or normal liver isoenzyme M2 (6 moles/mole protein).