Hexosephosphates produced by higher plants

Abstract

THE fact that phosphates stimulate the respiratory sugar metabolism in higher plants suggests that the formation of phosphoric esters may occur as part of this process. Stoklasa et al. [1904-1913] obtained cell-free zymase-like preparations from peas, beetroots , potatoes etc., which actively fermented sugars. Bodnar [1916] confirmed these results under strictly aseptic conditions, since some investigators had attributed Stoklasa's findings to bacterial contamination. Evidence of phosphorylation was first given by Bodnar [1925] who demonstrated that inorganic phosphate disappeared when added to ground peas in presence of toluene. His results were confirmed by Zalesky and Pissarjewski [1927] who did not however regard this process as a necessary step in the respiration and attributed the stimulation to alkalinity of the phosphate rather than to the formation of phosphoric esters. More recently, Rao [1935] has prepared active cell-free aqueous extracts by plasmolysing fermenting peas with light petroleum and states that in such extracts the decomposition of sugar and the phosphorylation are concomitant processes.

THE INFLUENCE OF LIGHT, TEMPERATURE, AND SOME ENZYME POISONS UPON THE TOTAL ORGANIC ACID CONTENT OF LEAF TISSUE OF KALANCHOE DAIGREMONTIANA (HAMET AND PERRIER)

“…One of these might be phosphoric acid and its esters, particularly the hexosephosphates. There is considerable evidence that these esters are present in plant tissues (4,15,21,40,41). In view of the recent work with phosphorylation in plant tissue extracts and intact plant organs (see STAUFFER, 39) it appears probable that during changes in carbohydrate content there may be changes in the relative amounts of various phosphate esters and their salts.…”

Transformation of Sugars in Plants

“…A mixture of the two esters was isolated by Robison from yeast and by Embden from muscle; these esters are also known to occur in higher plants (19). A phosphohexoisomerase capable of catalyzing the reversible interconversion of glucose-6-phosphate to fructose-6-phosphate and man nose-6-phosphate, was shown by Tank6 (20) to exist in pea extracts. Somers & Cosby (21) also found that fructose-6-phosphate is converted by pea seed extracts into an aldose monophosphate, presumed to be glucose-6-phosphate.…”

Reaction Paths in the Respiration of the Higher Plants

“…Pea meal has been a favorite material and, under appropriate conditions, accumulates glucose 1-phosphate in considerable quantities (76). Alternatively, fructose 1,Bdiphosphate and mixed hexose &phosphates have been isolated (76,191). Sedoheptulose phosphate has been identified in spinach leaf preparations fed with ribose 5-phosphate (10).…”