Phosphorylation in crested wheatgrass seeds at low water potentials

Crested wheatgrass seeds [Agropyron desertorum (Fisch. ex Link) Schult.] were tested for their ability to carry on phosphorylation reactions at low water potentials. Seeds were treated with (32)P labeled sodium phosphate and incubated in air having different controlled relative humidities. Ion exchange chromatography and radioassay of phosphate esters indicated that some phosphorylation occurred at a water potential of -880 atmospheres. Seeds did not incorporate (32)P in nicotinamide adenine dinucleotide, adenosine triphosphate, and uridine diphosphate hexose until they were moistened to a water potential of -130 atmospheres.

Hexose-, inositol-, and nucleoside phosphate esters in germinating seeds of crested wheatgrass

Net synthesis of phosphate esters was measured in crested wheatgrass seeds [Agropyron desertorum (Fisch.) Schult.] to learn what phosphorylating reactions occur in early stages of germination. Phosphate esters were separated on ion exchange columns and identified by cochromatography and chemical analyses. Synthesis of adenosine triphosphate and UDP-hexose was detected 6 hours after the beginning of water absorption. This synthesis occurred during the period of rapid increase in water potential. Synthesis of hexose phosphate and uridine triphosphate was detected 12 hours after the beginning of water absorption. The concentrations of these esters increased during 48 hours. Increases in concentration of inositol di-, tri-, and tetraphosphate suggested that hydrolysis of inositol hexaphosphate began after 12 hours.

Educational Measures for Prevention of Tuberculosis

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