Biomaterial Database

Soluble CuA-binding domain from the Paracoccus cytochrome c oxidase. 1993

P Lappalainen, and R Aasa, and B G Malmström, and M Saraste

European Molecular Biology Laboratory, Heidelberg, Germany.

In cytochrome c oxidase the C-terminal part of subunit II is outside the membrane and contains a copper center called CuA. We have expressed this domain of the Paracoccus denitrificans oxidase in a soluble form. Data obtained by quantitative copper-to-protein measurements, electrospray mass spectrometry, and electron paramagnetic resonance spectroscopy show that the center contains two copper atoms probably in a mixed valence configuration. Its absorbance spectrum is similar to that of the copper center A in nitrous oxide reductase. The EPR spectrum suggests that the center in the soluble protein is closely related to the native CuA site in the cytochrome oxidase complex. However, it seems likely that the copper center in the soluble domain is more exposed to the aqueous milieu than in the intact complex because its absorbance and EPR spectra are sensitive to pH. At alkaline pH one of the coppers in the site acquires type-2 character, indicating that it may be coordinated to a new ligand. The pK of this reversible change is about 8.2. The CuA-binding fragment is able to oxidize cytochrome c.

UI	MeSH Term	Description	Entries
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D010231	Paracoccus denitrificans	A species of bacteria isolated from soil.	Micrococcus denitrificans
D003300	Copper	A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.	Copper-63,Copper 63
D003576	Electron Transport Complex IV	A multisubunit enzyme complex containing CYTOCHROME A GROUP; CYTOCHROME A3; two copper atoms; and 13 different protein subunits. It is the terminal oxidase complex of the RESPIRATORY CHAIN and collects electrons that are transferred from the reduced CYTOCHROME C GROUP and donates them to molecular OXYGEN, which is then reduced to water. The redox reaction is simultaneously coupled to the transport of PROTONS across the inner mitochondrial membrane.	Cytochrome Oxidase,Cytochrome aa3,Cytochrome-c Oxidase,Cytochrome Oxidase Subunit III,Cytochrome a,a3,Cytochrome c Oxidase Subunit VIa,Cytochrome-c Oxidase (Complex IV),Cytochrome-c Oxidase Subunit III,Cytochrome-c Oxidase Subunit IV,Ferrocytochrome c Oxygen Oxidoreductase,Heme aa3 Cytochrome Oxidase,Pre-CTOX p25,Signal Peptide p25-Subunit IV Cytochrome Oxidase,Subunit III, Cytochrome Oxidase,p25 Presequence Peptide-Cytochrome Oxidase,Cytochrome c Oxidase,Cytochrome c Oxidase Subunit III,Cytochrome c Oxidase Subunit IV,Oxidase, Cytochrome,Oxidase, Cytochrome-c,Signal Peptide p25 Subunit IV Cytochrome Oxidase,p25 Presequence Peptide Cytochrome Oxidase
D004578	Electron Spin Resonance Spectroscopy	A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.	ENDOR,Electron Nuclear Double Resonance,Electron Paramagnetic Resonance,Paramagnetic Resonance,Electron Spin Resonance,Paramagnetic Resonance, Electron,Resonance, Electron Paramagnetic,Resonance, Electron Spin,Resonance, Paramagnetic
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D001483	Base Sequence	The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.	DNA Sequence,Nucleotide Sequence,RNA Sequence,DNA Sequences,Base Sequences,Nucleotide Sequences,RNA Sequences,Sequence, Base,Sequence, DNA,Sequence, Nucleotide,Sequence, RNA,Sequences, Base,Sequences, DNA,Sequences, Nucleotide,Sequences, RNA
D001665	Binding Sites	The parts of a macromolecule that directly participate in its specific combination with another molecule.	Combining Site,Binding Site,Combining Sites,Site, Binding,Site, Combining,Sites, Binding,Sites, Combining
D012997	Solvents	Liquids that dissolve other substances (solutes), generally solids, without any change in chemical composition, as, water containing sugar. (Grant & Hackh's Chemical Dictionary, 5th ed)	Solvent
D017931	DNA Primers	Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.	DNA Primer,Oligodeoxyribonucleotide Primer,Oligodeoxyribonucleotide Primers,Oligonucleotide Primer,Oligonucleotide Primers,Primer, DNA,Primer, Oligodeoxyribonucleotide,Primer, Oligonucleotide,Primers, DNA,Primers, Oligodeoxyribonucleotide,Primers, Oligonucleotide