The mitochondrial precursor protein apocytochrome c strongly influences the order of the headgroup and acyl chains of phosphatidylserine dispersions. A sup 2 H and sup 31 P NMR study

Journal Article · Tue Mar 06 04:00:00 EST 1990 · Biochemistry; (USA)

DOI:https://doi.org/10.1021/bi00461a015· OSTI ID:6940712

Jordi, W; de Kroon, A I.P.M.; Killian, A; de Kruijff, B ^[1]

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1. State Univ. of Utrecht (Netherlands)

Deuterium and phosphorus nuclear magnetic resonance techniques were used to study the interaction of the mitochondrial precursor protein apocytochrome c with headgroup-deuterated (dioleoylphosphatidyl-L-(2-{sup 2}H{sub 1})serine) and acyl chain deuterated (1,2-(11,11-{sup 2}H{sub 2})dioleoylphosphatidylserine) dispersions. Binding of the protein to dioleoylphosphatidylserine liposomes results in phosphorus nuclear magnetic resonance spectra typical of phospholipids undergoing fast axial rotation in extended liquid-crystalline bilayers with a reduced residual chemical shift anisotropy and an increased line width. {sup 2}H NMR spectra on headgroup-deuterated dioleoylphosphatidylserine dispersions showed a decrease in quadrupolar splitting and a broadening of the signal on interaction with apocytochrome c. Addition of increasing amounts of apocytochrome c to the acyl chain deuterated dioleoylphosphatidylserine dispersions results in the gradual appearance of a second component in the spectra with a 44% reduced quadrupolar splitting. Such large reduction of the quadrupolar splitting has never been observed for any protein studied yet. The induction of a new spectral component with a well-defined reduced quadrupolar splitting seems to be confined to the N-terminus since addition of a small hydrophilic amino-terminal peptide (residues 1-38) also induces a second component with a strongly reduced quadrupolar splitting. A chemically synthesized peptide corresponding to amino acid residues 2-17 of the presequence of the mitochondrial protein cytochrome oxidase subunit IV also has a large perturbing effect on the order of the acyl chains, indicating that the observed effects may be a property shared by many mitochondrial precursor proteins. Implications of these data for the import of apocytochrome c into mitochondria will be discussed.

• OSTI ID: 6940712
• Journal Information: Biochemistry; (USA), Journal Name: Biochemistry; (USA) Vol. 29:9; ISSN 0006-2960; ISSN BICHA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINO ACIDS
BIOCHEMISTRY
BODY
CARBOXYLIC ACIDS
CARDIOVASCULAR SYSTEM
CELL CONSTITUENTS
CHEMISTRY
COHERENT SCATTERING
CYTOCHROMES
DEUTERIUM COMPOUNDS
DIFFRACTION
HEART
HYDROGEN COMPOUNDS
HYDROXY ACIDS
ISOTOPES
LIGHT NUCLEI
MAGNETIC RESONANCE
MITOCHONDRIA
MOLECULAR STRUCTURE
NMR SPECTRA
NUCLEAR MAGNETIC RESONANCE
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANOIDS
ORGANS
PEPTIDES
PHOSPHOPROTEINS
PHOSPHORUS 31
PHOSPHORUS ISOTOPES
PIGMENTS
PROTEINS
RESONANCE
SCATTERING
SERINE
SPECTRA
STABLE ISOTOPES
X-RAY DIFFRACTION