Effect of clinorotation on growth and pigment biosynthesis in etiolated barley plants.

Altered gravity conditions (hyper- or hypogravity) leads to changes in metabolic processes in living organisms (Kordyum, 1997). One important subject of plant space biology is the investigation of the effects of microgravity conditions on the development of the photosynthetic apparatus. The impact of microgravity on the photosynthetic apparatus of plants has been studied in a number of space-flight experiments.

[Comparative study of inhibiting photophosphorylation and light-activated ATP hydrolysis in pea chloroplasts by N,N'-dicyclohexylcarbodiimide].

Inhibition kinetics of photophosporylation in chloroplast preparations preincubated by N,N'-dicyclohexylcarbodiimide (DCCD) in darkness has been studied. It was found that the higher membrane concentration the lower DCCD/chlorophyll relation sufficient for blocking of ATP synthesis and light-activated hydrolysis. Comparative studies of DCCD-inhibition of the ATP synthesis and light-activated hydrolysis showed that the latter process was more sensitive to DCCD.

Synergetic inhibition of photophosphorylation and uncoupled electron transport by N,N'-dicyclohexylcarbodiimide and alcohols in pea chloroplasts.

It is shown that the inhibitory effect of N,N'-dicyclohexylcarbodiimide (DCCD) on photophosphorylation and uncoupled electron transfer from H2O to methylviologen (MV) in pea chloroplasts depends upon solvent concentration. Being applied as a solution in dimethyl sulfoxide (DMSO) DCCD did not suppress uncoupled electron transfer and inhibited photophosphorylation independently from DMSO concentration. If DCCD was applied as methanolic or ethanolic solution its concentration sufficient for half-maximum inhibition [I]50 of both photophosphorylation and uncoupled electron transfer decreased at increasing alcohol content.

[Role of the molecular environment in chlorophyllase functioning during its immobilization on organic carriers].

Immobilization of chlorophyllase was performed on aminohexadecyl sepharose, aminoundecyl sepharose and heptyl sepharose. The enzyme activity lowers considerably and is rather close for all carriers. Essential differences are manifested in stability of the preparation during storage.