OXYGEN-AFFINITY OF TERMINAL OXIDASES IN SOYBEAN MITOCHONDRIA

Authors
MILLAR AH BERGERSEN FJ DAY DA
Citation
Ah. Millar et al., OXYGEN-AFFINITY OF TERMINAL OXIDASES IN SOYBEAN MITOCHONDRIA, Plant physiology and biochemistry, 32(6), 1994, pp. 847-852
Citations number
20
Categorie Soggetti
Plant Sciences
Journal title
Plant physiology and biochemistry → ACNP
ISSN journal
09819428
Volume
32
Issue
6
Year of publication
1994
Pages
847 - 852
Database
ISI
SICI code
0981-9428(1994)32:6<847:OOTOIS>2.0.ZU;2-Y
Abstract
Respiration of mitochondria isolated from roots and cotyledons of soyb ean seedlings was monitored over the range of 0 - 6 mu M oxygen, using oxyleghaemoglobin or oxymyoglobin as oxygen sources in a closed syste m. From the data obtained, apparent Km(oxygen) values of approximately 0.14 mu M for cytochrome oxidase and 1.7 mu M for the alternative oxi dase were calculated. The results indicate that the alternative oxidas e cannot operate under the microaerobic conditions thought to prevail in nitrogen-fixing root nodules.