Analysis of cytoplasmic membrane from wild type and mutantParacoccus denitrificanscontaining excess nitrate reductase protein and cytochromeb

✍ Scribed by Kathleen M. Calder; June Lascelles

• Publisher: Springer
• Year: 1984
• Tongue: English
• Weight: 709 KB
• Volume: 137
• Category: Article
• ISSN: 0302-8933
• DOI: 10.1007/bf00414548

✦ Synopsis

Cytoplasmic membranes were isolated from wild type and mutant strain M-1 of Paraeoeeus denitrificans grown with low aeration to promote synthesis of nitrate reductase protein and cytochrome b. The presence of 10-100-fold excess of nitrate reductase in the wild type or the corresponding enzymically inactive protein in the mutant did not significantly affect respiratory oxidase activities with NADH, sueeinate or TMPD-ascorbate as electron donor. A cytochrome b-nitrate reductase complex was resolved by isoelectric focussing of Triton X-100 solubflized membranes from the wild type grown with azide and from the mutant, whereas the enzyme complex from nitrate-grown wild type was not resolved from cytochrorne c. Preparations from azideinduced wild type or from the mutant could be a suitable source of the cytochrome b associated with nitrate reduetase for more detailed studies.