Subunit Composition of Cytochrome <i>c</i> Oxidase in Mitochondria of <i>Zea mays</i>

Hawkesford, Malcolm J.; Liddell, A; Leaver, Christopher J.

doi:10.1104/pp.91.4.1535

Cited by 18 publications

(10 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Gels were either silver-stained as described by Hawkesford et al (1989) or prepared for autoradiography as described below. After an overnight fixation in 45% (v/v) methanol/7.5 % (v/v) ethanoic acid, gels were immersed in 22 % (w/v) 2,5-diphenyloxazole (Park Scientific, Nottingham, UK) in ethanoic acid for 60 rain, followed by transfer to, and several brief washes in water for a total of 10 rain.…”

Section: Sample Preparation For Polyacrylamide Gel Electrophoresis (Pmentioning

confidence: 99%

Differential protein synthesis in response to sulphate and phosphate deprivation: Identification of possible components of plasma-membrane transport systems in cultured tomato roots

Hawkesford

Belcher

1991

Planta

View full text Add to dashboard Cite

Isolated roots of Lycopersicon esculentum Mill., cultured in axenic conditions were starved of sulphate or phosphate, and uptake capacities for the respective oxyanion-transport systems were observed for several days after sulphate or phosphate withdrawal. Sulphate-uptake capacity of the intact roots, measured in a 20-min period, increased from a control level of 100 nmol · g(-1) · h(-1) to 1100 nmol · g(-1) · h(-1) in 10 d, and phosphate-uptake capacity increased from 500 to 1400 nmol · g(-1) · h(-1) over 4 d. Newly synthesised polypeptides of these root cultures were pulse-labelled in vivo for 2 h, by adding [(3)H]leucine to the culture medium. The tissue was immediately homogenised and soluble and membrane fractions were prepared. A highly purified plasma-membrane fraction was separated from the crude microsomal membrane fraction using an aqueous two-phase partitioning technique. All fractions were analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and autoradiography. A 28-kilodalton (kDa) soluble polypeptide, and 36-, 43-, and 47-kDa plasma-membrane polypeptides were observed to have increased labelling after 4 d of sulphate deprivation. Longer periods resulted in additional polypeptides with increased [(3)H]leucine incorporation. The synthesis of a 25-kDa membrane polypeptide and a 65-kDa soluble polypeptide was increased after 4 d of phosphate deprivation. Two-dimensional electrophoresis afforded greater resolution of the plasmamembrane polypeptides, confirming increased synthesis of the 36-kDa polypeptide and the presence of the 28-kDa polypeptide in the plasma-membrane preparation from sulphate-starved roots. These polypeptides were also observed in protein-stained two-dimensional gels as low-abundant protein components of the plasmamembrane fraction. It is suggested that the 36-kDa polypeptide may be a component of the plasma-membrane sulphate-transport system and that the 25-kDa polypeptide may be a component of a phosphate-transport system.

show abstract

Section: Sample Preparation For Polyacrylamide Gel Electrophoresis (Pmentioning

confidence: 99%

Differential protein synthesis in response to sulphate and phosphate deprivation: Identification of possible components of plasma-membrane transport systems in cultured tomato roots

Hawkesford

Belcher

1991

Planta

View full text Add to dashboard Cite

show abstract

“…Further chromatographic purifications of cytochrome c oxidase complexes from pea, maize and wheat revealed similar banding patterns on denaturing polyacrylamide gels. In these organisms, cytochrome c oxidase was composed of the three mitochondrial-encoded Cox I, Cox II and Cox III subunits, one further subunit in the 18 kDa range, and additional proteins below 11 kDa which could not be resolved by gel electrophoresis (Matsuoka et al, 1981;Hawkesford et al, 1989;Pfeiffer et al, 1990). The nucleotide sequence of a nuclear gene encoding a protein resembling the CoxVb subunit from beef was characterized in rice (Kadowaki et al, 1996).…”

Section: Introductionmentioning

confidence: 98%

Mitochondrial cytochrome c oxidase and succinate dehydrogenase complexes contain plant specific subunits

et al. 2004

View full text Add to dashboard Cite

Respiratory oxidative phosphorylation represents a central functionality in plant metabolism, but the subunit composition of the respiratory complexes in plants is still being defined. Most notably, complex II (succinate dehydrogenase) and complex IV (cytochrome c oxidase) are the least defined in plant mitochondria. Using Arabidopsis mitochondrial samples and 2D Blue-native/SDS-PAGE, we have separated complex II and IV from each other and displayed their individual subunits for analysis by tandem mass spectrometry and Edman sequencing. Complex II can be discretely separated from other complexes on Blue-native gels and consists of eight protein bands. It contains the four classical SDH subunits as well as four subunits unknown in mitochondria from other eukaryotes. Five of these proteins have previously been identified, while three are newly identified in this study. Complex IV consists of 9-10 protein bands, however, it is more diffuse in Blue-native gels and co-migrates in part with the translocase of the outer membrane (TOM) complex. Differential analysis of TOM and complex IV reveals that complex IV probably contains eight subunits with similarity to known complex IV subunits from other eukaryotes and a further six putative subunits which all represent proteins of unknown function in Arabidopsis . Comparison of the Arabidopsis data with Blue-native/SDS-PAGE separation of potato and bean mitochondria confirmed the protein band complexity of these two respiratory complexes in plants. Two-dimensional Blue-native/Blue-native PAGE, using digitonin followed by dodecylmaltoside in successive dimensions, separated a diffusely staining complex containing both TOM and complex IV. This suggests that the very similar mass of these complexes will likely prevent high purity separations based on size. The documented roles of several of the putative complex IV subunits in hypoxia response and ozone stress, and similarity between new complex II subunits and recently identified plant specific subunits of complex I, suggest novel biological insights can be gained from respiratory complex composition analysis.

show abstract

“…There are two previous reports on the isolation of a bcl-complex from monocotyledons. Hawkesford et al (1989) and Pfeiffer et al (1990) used dodecyl maltoside or lauryl maltoside for solubilization and anion-exchange chromatography for partial purification of cytochrome-c reductase from maize and wheat. Here, we report on the purification of the wheat bCl-COmplex by solubilization with Triton X-100 and the employment of cytochrome-c affinity chromatography as introduced by Weiss and Juchs (1978) for the isolation of this enzyme complex from Neurospora.…”

Section: Introductionmentioning

confidence: 99%

The general mitochondrial processing peptidase from wheat is integrated into the cytochrome bc 1-complex of the respiratory chain

Braun

Emmermann

Kruft³

et al. 1995

Planta

View full text Add to dashboard Cite

The bc1-complex (EC 1.10.2.2.) from Triticum aestivum L. was purified by cytochrome-c affinity chromatography and gel filtration using either etiolated seedlings or wheat-germ extract as starting material. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the isolated enzyme revealed ten bands, which were analysed by immunoblotting and direct amino-acid sequencing. The enzyme from wheat is the first bc1-complex that is reported to contain four core proteins (55.5, 55.0, 51.5 and 51.0 kDa). In addition, the wheat bc1-complex comprises cytochrome b (35 kDa), cytochrome c1 (33 kDa) the "Rieske" iron-sulphur protein (25 kDa) and three small subunits < 15 kDa. This composition differs from the one reported in fungi, mammals and potato. Partial sequence determination of the large subunits suggests that the 55.5- and 55.0-kDa-proteins represent the beta-subunit of the general mitochondrial processing peptidase, and the 51.5- and 51.0-kDa proteins the alpha-subunit of this enzyme. The bc1-complex from wheat efficiently processes mitochondrial precursor proteins as shown in an in-vitro processing assay. In control experiments the isolated bc1-complexes from potato, yeast, Neurospora and beef, all purified by the same isolation procedure, were also tested for processing activity. Only the protein complexes from plants contain the general mitochondrial processing peptidase. The composition of the wheat bc1-complex sheds new light on the co-evolution of the processing peptidase and the middle segment of the respiratory chain.

show abstract

Subunit Composition of Cytochrome c Oxidase in Mitochondria of Zea mays

Abstract: Cytochrome c oxidase has been purified from Zea mays mitochondria by a solubilization with dodecyl maltoside followed by a simple and rapid two

Cited by 18 publications

References 24 publications

Differential protein synthesis in response to sulphate and phosphate deprivation: Identification of possible components of plasma-membrane transport systems in cultured tomato roots

Differential protein synthesis in response to sulphate and phosphate deprivation: Identification of possible components of plasma-membrane transport systems in cultured tomato roots

Mitochondrial cytochrome c oxidase and succinate dehydrogenase complexes contain plant specific subunits

The general mitochondrial processing peptidase from wheat is integrated into the cytochrome bc 1-complex of the respiratory chain

Contact Info

Product

Resources

About