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A New Approach for the Comparative Analysis of Multiprotein Complexes Based on 15N Metabolic Labeling and Quantitative Mass Spectrometry
Published on: March 13, 2014
Studies on cytochrome c oxidase, V. Polypeptide IV: alignment and amino acid sequences on cyanogen bromide fragments
Abstract:
The isolation and chemical characterization of polypeptide IV from beef heart cytochrome oxidase is described. The protein is one of the main (stoichiometric) components of the oxidase. It is the largest polypeptide of the enzyme synthezised in the cytoplasm and has, as such, also been identified in enzyme preparations from yeast and Neurospora. A partial sequence, consisting of 105 amino acid residues which give a frame work of the covalent structure of the polypeptide is obtained from N- anc C-terminal sequencing and from the cyanogen bromide fragments of the chain. The isolation and sequencing of the fragments of this membrane protein are discussed.
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