title: Oxidation of proline by plant mitochondria.
abstract: 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.
authors: Department of Agronomy, University of Illinois, Urbana, Illinois 61801.
authors: S F
authors: SF
authors: Boggess
authors: D E
authors: DE
authors: Koeppe