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M Avron

Publications and source records attributed to M Avron.

At least 109 records · Page 6Linked to original sources
PubMed1966

Laser activation of rapid absorption changes in spinach chloroplasts and chlorella.

The kinetics of the 520 mmu absorption change in spinach chloroplasts and Chlorella vulgaris following a flash from the ruby laser have been determined as follows: rise halftime </= 0.3 x 10(-6) second; rapid recovery halftime = 5 to 6 x 10(-6) second; intermediate recovery halftime = 4 x 10(-4) second (spinach chloroplasts only); slow recovery halftime = 12 to 170 x 10(-3) second, dependent on the measuring light intensity and aerobicity of the suspension.The rapid phase of the 520 mmu reaction is approximately independent of temperature, from 295 degrees to 77 degrees Absolute.With increasing oxygenation of the sample, the extent of the rapid phase decreases, the extent of the slow phase increases, while the extent of the intermediate phase in spinach chloroplasts remains constant.In spinach chloroplasts, no recovery halftime of the 3 recovery phases for the 520 mmu absorption change was observed to correspond to the halftime for oxidation of cytochrome f (t((1/2)) = 1.3 x 10(-3) second).

Journal Article↗
PubMed1966

Desaspidin: a nonspecific uncoupler of photophosphorylation.

The inhibitory effect of desaspidin is shown to depend on the oxidation-reduction state of the system investigated. The more reducing the conditions, the more desaspidin-inhibited the system and vice versa.The effect of desaspidin on noncyclic photophosphorylation induced by TPN(+), ferricyanide or DPIP is shown to be due to an uncoupling action.The decrease in effectiveness of desaspidin under oxidizing condition is shown to depend upon a photooxidation catalyzed by photosystem I of chloroplasts, which is prevented, but not reversed, by the presence of reducing agents, such as ascorbate + DPIP.These results are interpreted as indicating that, contrary to previous suggestions, desaspidin is a nonspecific uncoupler of all types of photophosphorylation.

Journal Article↗