Determination of the complete amino acid sequence of wheat germ cytochrome c has shown that the molecule consists of a single polypeptide chain of 112 residues. On alignment with mammalian cytochromes, the peptide chain extends for 8 residues at the NH&erminal end. In contrast with other cytochromes that have a peptide chain longer than 104 residues, the NHt-terminal residue is Nacetylalanine. ...

bacterium Thiobacillus X. A fifth fraction (acidic fraction) contained two additional cytochrome components with x bands at 550 and 557 msi respectively in the reduced state. 2. All the cytochromes appear to be ofthe c type, are labile to heat and acid and do not combine with carbon monoxide. They are auto-oxidizable to varying degrees. 3. Cytochromes 550 (1) and 557 (1) are basic, and are adso...

The structure of respiratory cytochrome c551 of Pseudomonas aeruginosa, with 82 amino acids, has been solved by x-ray analysis and refined to a crystallographic R factor of 16.2%. It has the same basic folding pattern and hydrophobic heme environment as cytochromes c, c2, and c550, except for a large deletion at the bottom of the heme crevice. This same "cytochrome fold" appears to be present i...

Multi-haem cytochromes are employed by a range of microorganisms to transport electrons over distances of up to tens of nanometres. Perhaps the most spectacular utilization of these proteins is in the reduction of extracellular solid substrates, including electrodes and insoluble mineral oxides of Fe(III) and Mn(III/IV), by species of Shewanella and Geobacter. However, multi-haem cytochromes ar...

Abs t r a : The most fiequently encountered function of cytochromes P450, the monooxygenation of substrates, is now well understood and depends on the involvement of a high-valent iron-0x0 intermediate. The corresponding reactions have been reproduced by using metalloporphyrin model systems, the most efficient catalysts being Fe(III) or Mn(III) tetraarylporphyrins bearing electronwithdrawing su...

Removal of lipid from detergent-solubilized succinate cytochrome c reductase by a mild method leads to a series of changes in the optical and EPR spectra of the b cytochromes. This culminates in a state that resembles purified b cytochromes from the same source and bisimidazole ferriheme model complexes. Reconstitution of the lipid-depleted complex with phospholipid restores the native spectra ...

redox potential of +355 mV at pH 7.0. The absorption spectra of both cytochromes c6 showed 4 mftxima in reduced form, and2 maxima and a weak peak at 695 nm in oxidized form. The pyridine ferrohemochrome spectra indicated that their prosthetic group was heme c. These physicochemical properties were similar to those of other algal cytochromes c6. The amino acids (88 residues) of CK5cyc6 and CK22c...