【摘要】 烟草愈伤组织中存在有大约占总呼吸20—30%的不被 KCN 加 m-CLAM 抑制的“剩余呼吸”,它的性质和在细胞中的定位都不清楚。本研究发现,乙醇酸和乙醛酸都明显促进不被KCN（或 NaN₃）加 m-CLAM 抑制的剩余呼吸;乙醇酸听引起的氧吸收和剩余呼吸可被α-羟基乙磺酸钠抑制;线粒体呼吸被 KCN 加 m-CLAM 完全抑制;除去线粒体的上清液中发现有乙醇酸和乙醛酸氧化活性的存在。初步确定,烟草愈伤组织中这部分剩余呼吸主要是由非线粒体乙醇酸氧化酶所催化的。更多还原

【Abstract】 A residual respiration not inhibited by KCN plus hydroxamic acid had been observed in many plant organs and tissues.The relative O₂ uptake of it was 20—30% of total respiration in tobacco callus cnltures.However,there is no report concerning the nature of the residual respiration and its localization in cell.The object of this study is to elucidate the characteris- tics of this residual respiration and its localization in cell.The experimental results are as follows: 1.The additions of glycolate and glyoxylate cause a marked rise in residual respiration not inhibited by KCN （or NaN₃） plus m-CLAM.2.The O₂ uptake induced by glyeolate and the residual respiration is inhibited by the addition of α-hydroxy ethanesulfonate.3.The mito- chondrial respiration is completely inhibited by KCN plus m-CLAM,but no effect by adding ,of glycolate.4.Oxidation reactions of glycolate and glyoxylate in supernatant are observed after mitochondria are removed. Based on the above results,it is suggested that the residual respiration not inhibited by KCN plus m-CLAM in tobacco callus cultures is primarily catalyzed by glycolic acid oxidase localized within microbodies.更多还原