Pyridine Nucleotides in the Thyroid

The stability of pyridine nucleotides.

Diphosphopyridine nucleotide and triphosphopyridine nucleotide when used in appropriate enzyme systems become exceedingly useful reagents for the measurement of almost any biochemical substance. A companion paper describes procedures for measuring each of the pyridine nucleotides, whether in the oxidized or reduced form, at concentrations as low as 1O-g M and in amounts as small as lo-l5 moles ...

Pyridine nucleotides in erythrocyte metabolism.

The fluorometric measurement of pyridine nucleotides.

Measurement of DPNH’ or TPNH by absorption at 344 rnp has been a standard procedure for many years and has been used to study innumerable enzyme reactions. In spite of the proved value of this calorimetric method, there may be advantages in fluorometric methods for the pyridine nucleotides. First, it has been found practicable with a fluorometer to determine separately oxidized and reduced pyri...

A structure of pyridine nucleotides in solution.

Re-examination of the structure of pyridine coenzymes in solution by use of the 220-MHz high-frequency nuclear magnetic resonance spectrometer indicates that there is primarily one folded structure that is in rapid equilibrium with an open form. Reduced DPN(+) and reduced analogs of DPN(+) exist predominantly with the B side of the dihydropyridine ring folded against the adenine moiety. (The ox...

Pyridine Nucleotides in Erythrocyte Metabolism * RUTH

In recent years investigations of erythrocyte metabolism have been concerned with the interrelationships of enzymes, coenzymes, substrates, cofactors, and pH, inter alia (1-8). Although data have accumulated on these various aspects of the metabolism of normal and pathological erythrocytes, little direct information has been available heretofore on pyridine nucleotide coenzymes, despite their i...