The amino acid sequence of a snail cytochrome c has been determined. The molecule consists of a single polypeptide chain of 104 residues, and is homologous with other mitochondrial cytochromes c. Unlike the cytochromes c from vertebrates, there is no acetyl blocking group at the N-terminus. A change in an otherwise invariant position has been observed in position 87. Comparison with amino acid ...

The complete amino acid sequence of Neurospora crassa cytochrome c has been determined. The molecule consists of a single polypeptide chain containing 107 residues. The NH2-terminal residue is glycine, and the COOH-terminal residue is alanine. There are 39 amino acid differences between the cytochromes of N. crassa and those of the yeast Saccharomyces cerevisiae, whereas there are 43 amino acid...

The cytochrome systems of two classes of aquatic fungi, the Oomycetes and Chytridiomycetes, were studied by means of reduced-minus-oxidized difference spectra at room and at low temperature. At room temperature, all of these fungi have a c-type cytochrome with an absorption maximum at 551 mmu and a b-type cytochrome at 564 mmu. The Oomycetes have a-type cytochromes at 605 mmu, and the Chytridio...

Vertebrate cytochromes c and the cytochromes c of insects and plants have, on average, dipole moments of 320 and 340 debye, respectively. The direction of the dipole vector with respect to the haem plane, at the solvent-accessible edge of which electron transfer presumably takes place, is conserved in these two groups-at 32 ’ f 7” and 22” + lo”, respectively. The variation of dipole orientation...

c-Type cytochromes are characterized by covalent attachment of haem to protein through thioether bonds between the vinyl groups of the haem and the thiols of a Cys-Xaa-Xaa-Cys-His motif. Proteins of this type play crucial roles in the biochemistry of the nitrogen cycle. Many Gram-negative bacteria use the Ccm (cytochrome c maturation) proteins for the post-translational haem attachment to their...

24 Geobacter species are important Fe(III) reducers in a diversity of soils and sediments. 25 Mechanisms for Fe(III) oxide reduction have been studied in detail in Geobacter sulfurreducens, 26 but a number of the most thoroughly studied outer surface components of G. sulfurreducens, 27 particularly c-type cytochromes, are not well conserved among Geobacter species. In order to 28 identify cellu...

c-type cytochromes are characterized by the presence of two covalent bonds linking heme to apocytochrome and by the heme attachment motif in the apoprotein. Several molecular systems for the maturation of c-type cytochromes have evolved in different organisms. The best characterized are three of them: system I, system II and system III. Heme is synthesized in bacterial cytoplasm, in plastids, a...