Department of Agronomy, University of Illinois, Urbana, Illinois 61801.
Plant Physiol. 1978 Jul;62(1):22-5. doi: 10.1104/pp.62.1.22.
Mitochondria isolated from etiolated shoots of corn (Zea mays), wheat (Triticum aestivum), barley (Hordeum vulgare), soybean (Glycine max L. Merr.), and mung bean (Phaseolus aureus) exhibited a proline-dependent O(2) uptake subject to respiratory control. ADP/O ratios with proline as substrate were intermediate between ratios obtained with exogenous NADH and malate + pyruvate as substrates. Isotope studies showed proline metabolism to be dependent on O(2), but not NAD. The major ninhydrin-positive product formed via Delta(1)-pyrroline-5-carboxylic acid was glutamate. Mitochondria were capable of further metabolism of glutamate, as radioactive CO(2), organic acids, and aspartate were recovered after [(14)C]proline feeding experiments. These results demonstrate the mitochondrial association and O(2) dependence of plant proline metabolism.
从玉米（Zea mays）、小麦（Triticum aestivum）、大麦（Hordeum vulgare）、大豆（Glycine max L. Merr.）和绿豆（Phaseolus aureus）黄化苗中分离出的线粒体表现出依赖脯氨酸的 O(2)摄取，受呼吸控制。以脯氨酸为底物的 ADP/O 比值介于用外源 NADH 和苹果酸+丙酮酸为底物获得的比值之间。同位素研究表明，脯氨酸代谢依赖于 O(2)，而不依赖于 NAD。通过 Delta(1)-吡咯啉-5-羧酸形成的主要茚三酮阳性产物是谷氨酸。线粒体能够进一步代谢谷氨酸，因为在 [(14)C]脯氨酸喂养实验后回收放射性 CO(2)、有机酸和天冬氨酸。这些结果表明植物脯氨酸代谢与线粒体有关且依赖于 O(2)。
