Leghemoglobin and Rhizobium Respiration
نویسنده
چکیده
INTRODUCTION ..................................................................................... 444 LEGHEMOGLOBIN ................................................................................. 445 Occurrence, Purification, Sequence Analysis ................................................ 445 Biosynthesis and its Control; Genetic Origin ................................................ 446 Maintenance, Turnover, and Degradation ................................................... 448 Leghemoglobin Structure in Relation to Oxygen Reactivity ............................... 449 lntracellular Location of Leghemoglobin ..................................................... 451 LEGUME BACTEROIDS AND THE OXYGEN PARADOX ................................ 452 Nitrogenase Location and Oxygen Lability: Possible Protective Mechanisms ......... 452 Cytochrome Variation Among Free-living Rhizobia and Bacteroids ..................... 453 Periplasmic Location of Bacteroid Oxidases? ............................................... 455 LEGHEMOGLOBIN A D RHIZOBIUM RESPIRATION EFFICIENCY ................. 457 Oxygen Delivery and Other Possible Leghemoglobin Functions ......................... 457 The Soybean Symbiosis: Recognition of Efficient and Inefficient Phases of Bacteroid Respiration ........................................................................... 459 Other Legume Symbioses: Evidence for Increasing Oxygen Tolerance ................. 461 Respiration Substrate in Relation to Symbiotic Efficiency ................................. 466 Hemoglobin Nonlegume Symbioses ......................................................... 468 Rhizobium Nitrogen Fixation Without Leghemoglobin ..................................... 470 CONCLUSIONS ...................................................................................... 471
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