Formation of sucrose from malate in germinating castor beans. I. Conversion of malate to phosphoenol-pyruvate.
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چکیده
composed of all the valence electrons of the specimen. In this case, the electrons of the metal are coupled via the photon gas; their actions are not completely independent. Such a situation is not the case in the usual photosynthetic system; equilibrium or quasiequilibrium ideas may not be applied. In this situation each photosynthetic event is completely independent of the other events taking place at other sites in the material. Although in such a complicated system as the photosynthetic unit there could conceivably be a number of events which would use up the electronic energy imparted by photon absorption (such as fluorescence, radiationless transition, etc.). the individual photoelectron interactions are beyond the region of applicability of the second law of thermodynamics and are limited only by the conservation of energy and momentum. ACKNOWLEDGMENT
منابع مشابه
Formation of Sucrose From Malate in Germinating Castor Beans . II. Reaction Sequence From Phosphoenol-Pyruvate to Sucrose.
M14late is a key intermiie(liate in converting acetyl units to sucrose in germinating castor beans (8). In an earlier paper evidence wsas presente(d to show that a mechanism exists for the pro(luction of phosphoenol-pyruvate from nmalate in this material andl that phosphoenol-I)yruvate is an interme(liate in the production of sucrose fromii malate (6). In this paper indivi(lual reactions which ...
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of conversion of fat to carbohydrate in germinating castor beans. Of the four requisite enzymes, isocitritase (Equation 3) has been demonstrated by direct assay (l), while the presence of condensing enzyme (Equation 1), aconitase (Equation 2), and malate synthetase activity (Equation 4) has been inferred from isotope incorporation data. The rates of condensing enzyme and malate synthetase, as e...
متن کاملEnzymes of the Glyoxylate Cycle in Germinating
of conversion of fat to carbohydrate in germinating castor beans. Of the four requisite enzymes, isocitritase (Equation 3) has been demonstrated by direct assay (l), while the presence of condensing enzyme (Equation 1), aconitase (Equation 2), and malate synthetase activity (Equation 4) has been inferred from isotope incorporation data. The rates of condensing enzyme and malate synthetase, as e...
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During the germination of fatty seeds such as the castor bean, a rapid conversion of fat to sugar occurs (2). The fatty acids are probably broken down to acetyl units via P-oxidation (3) ; the discovery of the glyoxylate cycle enzymes (4) in the castor bean endosperm (5) provided a mechanism whereby these acetyl units could be quantitatively converted to malate. Since malate could be viewed as ...
متن کاملPyruvate Dehydrogenase Complex from Germinating Castor Bean
Subceliular organelles from castor bean (Ricuns commnwuis) endosperm were isolated on discontinuous sucrose gradients from germinating seeds which were 1 to 7 days postbit o. Marker enzyme activities of the organeUes were measured (fumarase, catalase, and triose phosphate isomerase) and the homogeneity of the organelle fractions was examined by electron microscopy. Pyrumate dehydrogenase comple...
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عنوان ژورنال:
- Plant physiology
دوره 36 5 شماره
صفحات -
تاریخ انتشار 1961