Processing peptidase of Neurospora mitochondria. Two-step cleavage of imported ATPase subunit 9
Please always quote using this URN: urn:nbn:de:bvb:20-opus-62674
- Subunit 9 (dicyclohexylcarbodümide binding protein, 'proteolipid') of the mitochondrial F 1F0-ATPase is a nuclearly coded protein in Neurospora crassa. lt is synthesized on free cytoplasmic ribosomes as a larger precursor with an NH2-terminal peptide extension. The peptide extension is cleaved ofT after transport of the protein into the mitochondria. A processing activity referred to as processing peptidase that cleaves the precursor to subunit 9 and other mitochondrial proteins is described and characterized using a cell-free system. PrecursorSubunit 9 (dicyclohexylcarbodümide binding protein, 'proteolipid') of the mitochondrial F 1F0-ATPase is a nuclearly coded protein in Neurospora crassa. lt is synthesized on free cytoplasmic ribosomes as a larger precursor with an NH2-terminal peptide extension. The peptide extension is cleaved ofT after transport of the protein into the mitochondria. A processing activity referred to as processing peptidase that cleaves the precursor to subunit 9 and other mitochondrial proteins is described and characterized using a cell-free system. Precursor synthesized in vitro was incubated with extracts of mitochondria. Processing peptidase required Mn2 + for its activity. Localization studies suggested that it is a soluble component of the mitochondrial matrix. The precursor was cleaved in two sequential steps via an intermediate-sized polypeptide. The intermediate form in the processing of subunit 9 was also seen in vivo and upon import of the precursor into isolated mitochondria in vitro. The two dcavage sites in the precursor molecule were determined. The data indicate that: {a) the correct NH2-terminus of the mature protein was generated, (b) the NH2-terminal amino acid of the intermediate-sized polypeptide is isoleueine in position -31. The cleavage sites show similarity ofprimary structure. It is concluded that processing peptidase removes the peptide extension from the precursor to subunit 9 (and probably other precursors) after translocation of these polypeptides (or the NHrterminal part of these polypeptides) into the matrix space of mitochondria.…
Author: | B. Schmidt, E. Wachter, Walter Sebald, W. Neupert |
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URN: | urn:nbn:de:bvb:20-opus-62674 |
Document Type: | Journal article |
Faculties: | Fakultät für Biologie / Theodor-Boveri-Institut für Biowissenschaften |
Language: | English |
Year of Completion: | 1984 |
Source: | In: European Journal of Biochemistry (1984 Nov 2) 144(3) 581-588. |
Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 57 Biowissenschaften; Biologie / 570 Biowissenschaften; Biologie |
GND Keyword: | Biochemie |
Release Date: | 2012/04/26 |
Licence (German): | Deutsches Urheberrecht |