Changes in the Carbohydrates of Allomyces Macrogynus During the Selective Development of Either Zoosporangia or Resistant Sporangia

Abstract

Allomyces macrogynus synthesized trehalose but did not appear to metabolize it. Trehalose was released to the suspending medium before the development of zoosporangia by plants suspended in water and before the development of resistant sporangia by plants in glutamic acid and glucose solution. Plants in the latter solution accumulated high levels of glycogen and trehalose before mRNA was transcribed for the development of resistant sporangia. Before the transcription of mRNA for either zoosporangia or resistant sporangia there was a period during which the plant content of glycogen, trehalose, protein and nucleic acid was constant. The increase in wall glycans and chitin during the development of zoosporangia was measured and possible origins of the walls are discussed.

Oxine, Ferric Oxine and Copper Oxine as Inhibitors of Growth and Differentiation of Allomyces macrogynus

“…With oxine present, the initial rate of metabolism of glucose was maintained for 1 h and thereafter declined but glucose metabolism had not ceased at 5 h. The growing culture maintained constant levels of 20-30 Ilg/mg dry weight of glycogen and 10-15Ilg/mg of trehalose until vegetative growth ceased. Then both commenced to rise to new peak concentrations like those found in the earlier work [approximately 100 Ilg/mg for glycogen and 35llg/mg for trehalose (Youatt 1980c)]. In the presence of oxine the concentration of trehalose immediately began to rise and increased at a faster rate to a peak of about 70 Ilg/mg.…”

“…The methods used in this work have already been described: culture methods using the defined medium which contains four amino acids and glucose are given in Youatt (1980a); fractionation of plants and analytical methods for protein, RNA and phosphate are described by Youatt (1980b); and assays of glucose, glycogen, trehalose, wall glycan and wall chitin by Youatt (1980c).…”

“…Oxine at concentrations which prevented the development of sporangia had no effect on the redistribution of phosphate. Youatt (1980c) showed that plants transferred to glucose-glutamate solution immediately began to accumulate trehalose and glycogen. In the presence of oxine there was no change in glycogen synthesis but increased accumulation of trehalose was observed.…”

“…The changes, recorded previously (Youatt 1980b(Youatt , 1980c, included the degradation of RNA and release of phosphate. Glycogen was maintained at approximately constant low levels and trehalose was released.…”

“…Analyses of changes in carbohydrates were also made, to follow accumulation of glycogen and trehalose in the presence of glucose and sodium glutamate as well as to follow the synthesis of wall glycan and wall chitin (Youatt 1980c). In this paper plants were exposed to oxine, iron oxine and copper oxine and the suspending media and the plants were analysed as in previous studies (Youatt 1980a(Youatt , 1980b(Youatt , 1980c.…”