Te May Ching

Fatty Acids in Pollen of Some Coniferous Species

Fatty acids in pollen of five coniferous species were isolated and analyzed by gas-liquid chromatography. It was found that 0.76 to 0.89 percent of the dry weight of pollen was fatty acid in three species of Pseudotsuga and 1.25 to 1.33 percent in two species of Pinus. Major components in Pseudotsuga were oleic, palmitic, and linoleic acids, whereas in Pinus they were linolenic, oleic, palmitic, and stearic acids.

Regulation of nitrogenase activity in soybean nodules by ATP and energy charge

Abstract Nonphosphorylating condition under anaerobiosis stopped nitrogenase activity in nodules of soybean ( Glycine max var. Chippewa) in less than three minutes and aeration quickly activated the enzyme. This stop-and-go treatment can be repeatedly applied on excised nodules, and a concomitant low-and-high ATP and energy charge (EC) was observed. After 2 minutes under anaerobiosis, nodule ATP and EC were decreased, respectively, to 20 and 40% of the control. These decreases were not as great with longer anaerobic treatments, and there was no change in the content of total adenosine phosphates. Oxygen enrichment (40%) stimulated the activity of nitrogenase by 2.5 fold in four minutes with a concomitant increase of ATP and EC by 40% and 14%, respectively, and an exhaustion of AMP. Longer treatments of oxygen enrichment lessened the initial effects. These findings indicate that ATP and energy charge probably regulate the activity of nitrogenase in vivo and an active adenylate kinase must be operating in the nodules to maintain an energy supply for the basal metabolism and for the nitrogenase under temporary stressed conditions.

ATP content and pollen germinability of some conifers

Abstract ATP content in air-dried pollen of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), noble fir (Abies procera Rehd.), and western hemlock (Tsuga heterophylla (Raf.) Sarg.) was found to be correlated significantly with germinability. ATP level appears to be a good biochemical index with which to predict pollen germinability in less than 20 min.