Identification of a copper protein as part of the nitrous oxide-reducing system in nitrite-respiring (denitrifying) pseudomonads
✍ Scribed by Teruo Matsubara; Walter G. Zumft
- Publisher
- Springer
- Year
- 1982
- Tongue
- English
- Weight
- 782 KB
- Volume
- 132
- Category
- Article
- ISSN
- 0302-8933
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✦ Synopsis
Copper is the essential transition element for nitrous oxide respiration in Pseudomonasperfectomarinus. Two novel kinds of copper proteins were detected in this organism. Their distribution was studied under different growth conditions and in other pseudomonads, as well as their association with N20 reduction of intact cells. A low molecular mass Copper protein (M~ 38,000) with a single absorption band at 340 nm (oxidized form), was found only in P. perfectomarinus and was not required for N20 reduction. N20 respiration was consistently associated with a high molecular mass copper protein (Mr 120,000) in P. perfectomarinus, Pseudomonas stutzeri, and in strains of Pseudomonasfluorescens that were capable of this type of respiration. The oxidized protein was violet to pink with absorption bands at 350, 480, 530, 620, and 780 nm. Pseudomonas chlororaphis and Pseudomonas aureofaciens which did not respire with N2O as electron acceptor, did not contain the novel type of copper protein. Cytochrome patterns were compared in these denitrifying pseudomonads to search for the physiological electron carrier to NzO reductase. The content and nature of the soluble c-type cytochromes depended strongly on the species and the particular growth condition.