Details
| Original language | English |
|---|---|
| Pages (from-to) | 306-310 |
| Number of pages | 5 |
| Journal | BBA - Bioenergetics |
| Volume | 1142 |
| Issue number | 3 |
| Publication status | Published - 6 May 1993 |
| Externally published | Yes |
Abstract
A soluble heterodimeric enzyme localized in the matrix space of fungal and mammalian mitochondria removes the presequences of mitochondrial precursor proteins. It consists of two subunits, the matrix processing peptidase (MPP) and the so-called processing enhancing protein (PEP). We have used antibodies directed against the matrix processing peptidase from fungi to analyse the corresponding plant enzyme and its submitochondrial localization. Antibodies directed against PEP specifically recognize two polypeptides of 55 kDa and 53 kDa which are exclusively present in the membrane fraction of potato mitochondria. Also the processing activity removing the presequences of precursor proteins synthesized in vitro is found in this fraction suggesting that the immunopositive proteins may be involved in the processing reaction. As it has been shown that in potato MPP forms part of cytochrome c reductase, a protein complex of the respiratory chain, we analysed this complex with antibodies against PEP. The 55 kDa and 53 kDa subunits are recognized by antibodies directed against PEP from yeast and Neurospora. Incubation of potato cytochrome c reductase with plant mitochondrial precursor proteins synthesized in vitro shows that the purified complex itself has processing activity. Molecular and functional analysis of the two immuno-positive subunits may now reveal which of these represents the processing enhancing protein of the mitochondrial processing peptidase from potato.
Keywords
- (Potato), Cytochrome c reductase, Mitochondrion, Processing peptidase, Protein import
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
- Biophysics
- Biochemistry, Genetics and Molecular Biology(all)
- Biochemistry
- Biochemistry, Genetics and Molecular Biology(all)
- Cell Biology
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In: BBA - Bioenergetics, Vol. 1142, No. 3, 06.05.1993, p. 306-310.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - The two high molecular weight subunits of cytochrome c reductase from potato are immunologically related to the mitochondrial processing enhancing protein
AU - Emmermann, Michael
AU - Braun, Hans-Peter
AU - Schmitz, Udo
N1 - Funding information: We are gratefutl o ProfessoGr . Schatz,B aseland ProfessorW . NeupertM, finchen,f or the gift of anti-bodiesa gainsbt oths ubunitso f the matrixp rocessing peptidasfer omy easta nd Neurospora. This work was supportedb y the DeutscheF orschungsgemeinschaft grantS chm6 98/2-2.
PY - 1993/5/6
Y1 - 1993/5/6
N2 - A soluble heterodimeric enzyme localized in the matrix space of fungal and mammalian mitochondria removes the presequences of mitochondrial precursor proteins. It consists of two subunits, the matrix processing peptidase (MPP) and the so-called processing enhancing protein (PEP). We have used antibodies directed against the matrix processing peptidase from fungi to analyse the corresponding plant enzyme and its submitochondrial localization. Antibodies directed against PEP specifically recognize two polypeptides of 55 kDa and 53 kDa which are exclusively present in the membrane fraction of potato mitochondria. Also the processing activity removing the presequences of precursor proteins synthesized in vitro is found in this fraction suggesting that the immunopositive proteins may be involved in the processing reaction. As it has been shown that in potato MPP forms part of cytochrome c reductase, a protein complex of the respiratory chain, we analysed this complex with antibodies against PEP. The 55 kDa and 53 kDa subunits are recognized by antibodies directed against PEP from yeast and Neurospora. Incubation of potato cytochrome c reductase with plant mitochondrial precursor proteins synthesized in vitro shows that the purified complex itself has processing activity. Molecular and functional analysis of the two immuno-positive subunits may now reveal which of these represents the processing enhancing protein of the mitochondrial processing peptidase from potato.
AB - A soluble heterodimeric enzyme localized in the matrix space of fungal and mammalian mitochondria removes the presequences of mitochondrial precursor proteins. It consists of two subunits, the matrix processing peptidase (MPP) and the so-called processing enhancing protein (PEP). We have used antibodies directed against the matrix processing peptidase from fungi to analyse the corresponding plant enzyme and its submitochondrial localization. Antibodies directed against PEP specifically recognize two polypeptides of 55 kDa and 53 kDa which are exclusively present in the membrane fraction of potato mitochondria. Also the processing activity removing the presequences of precursor proteins synthesized in vitro is found in this fraction suggesting that the immunopositive proteins may be involved in the processing reaction. As it has been shown that in potato MPP forms part of cytochrome c reductase, a protein complex of the respiratory chain, we analysed this complex with antibodies against PEP. The 55 kDa and 53 kDa subunits are recognized by antibodies directed against PEP from yeast and Neurospora. Incubation of potato cytochrome c reductase with plant mitochondrial precursor proteins synthesized in vitro shows that the purified complex itself has processing activity. Molecular and functional analysis of the two immuno-positive subunits may now reveal which of these represents the processing enhancing protein of the mitochondrial processing peptidase from potato.
KW - (Potato)
KW - Cytochrome c reductase
KW - Mitochondrion
KW - Processing peptidase
KW - Protein import
UR - http://www.scopus.com/inward/record.url?scp=0027294885&partnerID=8YFLogxK
U2 - 10.1016/0005-2728(93)90158-C
DO - 10.1016/0005-2728(93)90158-C
M3 - Article
AN - SCOPUS:0027294885
VL - 1142
SP - 306
EP - 310
JO - BBA - Bioenergetics
JF - BBA - Bioenergetics
SN - 0005-2728
IS - 3
ER -