INVESTIGADORES
ZABALETA Eduardo Julian
artículos
Título:
Carbonic anhydrase subunits form a matrix-exposed domain attached to the membrane arm of mitochondrial complex I in plants
Autor/es:
SUNDERHAUS, S.; HEINEMEYER, H.; KLODMAN, J.; JEANSCH, L.; DUDKINA, N.; PERALES, M.; EDUARDO JULIAN ZABALETA; BOEKEMA, E.; BRAUN, H.
Revista:
JOURNAL OF BIOLOGICAL CHEMISTRY
Editorial:
The American Society for Biochemistry and Molecular Biology, Inc.
Referencias:
Año: 2006 vol. 281 p. 6482 - 6488
ISSN:
0021-9258
Resumen:
Complex I of Arabidopsis includes five structurally related subunits
representing -type carbonic anhydrases termed CA1, CA2,
CA3, CAL1, and CAL2. The position of these subunits within complex
I was investigated. Direct analysis of isolated subcomplexes of
complex I by liquid chromatography linked to tandem mass spectrometry
allowed the assignment of the CA subunits to the membrane
arm of complex I. Carbonate extraction experiments revealed
that CA2 is an integral membrane protein that is protected upon
protease treatment of isolated mitoplasts, indicating a location on
the matrix-exposed side of the complex. A structural characterization
by single particle electron microscopy of complex I from the
green alga Polytomella and a previous analysis from Arabidopsis
indicate a plant-specific spherical extra-domain of about 60A¢ª in
diameter, which is attached to the central part of the membrane arm
of complex I on its matrix face. This spherical domain is proposed to
contain a heterotrimer of three CA subunits, which are anchored
with their C termini to the hydrophobic arm of complex I. Functional
implications of the complex I-integrated CA subunits are
discussed.
CA3, CAL1, and CAL2. The position of these subunits within complex
I was investigated. Direct analysis of isolated subcomplexes of
complex I by liquid chromatography linked to tandem mass spectrometry
allowed the assignment of the CA subunits to the membrane
arm of complex I. Carbonate extraction experiments revealed
that CA2 is an integral membrane protein that is protected upon
protease treatment of isolated mitoplasts, indicating a location on
the matrix-exposed side of the complex. A structural characterization
by single particle electron microscopy of complex I from the
green alga Polytomella and a previous analysis from Arabidopsis
indicate a plant-specific spherical extra-domain of about 60A¢ª in
diameter, which is attached to the central part of the membrane arm
of complex I on its matrix face. This spherical domain is proposed to
contain a heterotrimer of three CA subunits, which are anchored
with their C termini to the hydrophobic arm of complex I. Functional
implications of the complex I-integrated CA subunits are
discussed.
-type carbonic anhydrases termed CA1, CA2,
CA3, CAL1, and CAL2. The position of these subunits within complex
I was investigated. Direct analysis of isolated subcomplexes of
complex I by liquid chromatography linked to tandem mass spectrometry
allowed the assignment of the CA subunits to the membrane
arm of complex I. Carbonate extraction experiments revealed
that CA2 is an integral membrane protein that is protected upon
protease treatment of isolated mitoplasts, indicating a location on
the matrix-exposed side of the complex. A structural characterization
by single particle electron microscopy of complex I from the
green alga Polytomella and a previous analysis from Arabidopsis
indicate a plant-specific spherical extra-domain of about 60A¢ª in
diameter, which is attached to the central part of the membrane arm
of complex I on its matrix face. This spherical domain is proposed to
contain a heterotrimer of three CA subunits, which are anchored
with their C termini to the hydrophobic arm of complex I. Functional
implications of the complex I-integrated CA subunits are
discussed.