The intracellular distribution of cytochrome components and of oxidative enzyme activity in rat liver

Strittmatter, Cornelius F.; Ball, Eric G.

doi:10.1002/jcp.1030430105

Cited by 79 publications

(24 citation statements)

References 16 publications

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“…In deoxycholate extracts (0.5 per cent deoxycholate) the main peak of the pigment was shifted to 415 m]z and three much smaller peaks appeared at 350, 540, and 575 m/~ respectively. This hemeprotein is probably identical with the one described by Strittmatter and Ball (29,30) as a "cytochrome m," distinct from the other cytochromes of the cytoplasm.…”

Section: The Microson~essupporting

confidence: 75%

“…In the case of the microsome fraction, aliquots were taken in each experiment for: (a) fixation and subsequent electron microscopy and (b) chemical determinations. These latter comprised quantitative measurements of ribonucleic acid (RNA), protein nitrogen (P-N), and phospholipide phosphorus (PLP-P), as well as determinations of more characteristic microsomal components, e.g., the hemochromogen described by Strittmatter and Ball (29,30) and the enzyme diphosphopyridine nucleotide-cytochrome c reductase studied by Hogeboom (31).…”

Section: General Plan Of the Experimentsmentioning

confidence: 99%

“…The hemochromogen (30) was extracted by alcohol and alcohol-ether and the absorption shown by the extract at 400 rap (absorption peak in alcohol) was used as a measure of the amount of pigment present.…”

Section: Chemistrymentioning

confidence: 99%

“…nucleic acid complexes of maeromolecular dimensions (51). In biochemistry it has been used for the solubilization of mitochondrial cytoehromes (52) as well as for the solubilization of microsomal hemochromogen (29,30) and glucose-6-phosphatase (53).…”

Section: Deoxy6holate Treatment--mentioning

confidence: 99%

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Liver Microsomes

Palade

Siekevitz

1956

The Journal of Cell Biology

891

223

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Rat liver, liver homogenates, and microsome fractions separated therefrom were examined systematically in the electron microscope in sections of OsO4-fixed, methacrylate-embedded tissue and pellets. It was found that most microsomes are morphologically identical with the rough surfaced elements of the endoplasmic reticula of hepatic cells. They appear as isolated, membrane-bound vesicles, tubules, and cisternae which contain an apparently homogeneous material of noticeable density, and bear small, dense particles (100 to 150 A) attached to their outer aspect. In solutions of various osmolar concentrations they behave like osmometers. The findings suggest that they derive from the endoplasmic reticulum by a generalized pinching-off process rather than by mechanical fragmentation. The microsome fractions contain in addition relatively few vesicles free of attached particles, probably derived from the smooth surfaced parts of the endoplasmic reticula. Dense, peribiliary bodies represent a minor component of the same fractions. The microsomes derived from 1 gm. wet weight liver pulp contained (averages of 10 experiments) 3.09 mg. protein N, 3.46 mg. RNA (RNA/protein N = 1.12), and 487 µg. phospholipide P. They displayed DPNH-cytochrome c reductase activity and contained an alcohol-soluble hemochromogen. The microsome preparations proved resistant to washing and "aging." Treatment with versene and incubation with ribonuclease (30 minutes at 37°C.) resulted in appreciable losses of RNA and in partial or total disappearance of attached particles. Treatment with deoxycholate (0.3 to 0.5 per cent, pH = 7.5) induced a partial clarification of the microsome suspensions which, upon centrifugation, yielded a small pellet of conglomerated small, dense particles (100 to 150 A) with only occasionally interspersed vesicles. The pellet contained ∼80 to 90 per cent of the RNA and ∼20 per cent of the protein N of the original microsomes. The supernatant accounted satisfactorily for the materials lost during deoxycholate treatment. The findings suggest that the microsomal RNA is associated with the small particles whereas most of the protein and nearly all of the phospholipide, hemochromogen, and DPNH-cytochrome c reductase activity are associated with the membrane or content of the microsomes.

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Section: The Microson~essupporting

confidence: 75%

Section: General Plan Of the Experimentsmentioning

confidence: 99%

Section: Chemistrymentioning

confidence: 99%

Section: Deoxy6holate Treatment--mentioning

confidence: 99%

See 2 more Smart Citations

Liver Microsomes

Palade

Siekevitz

1956

The Journal of Cell Biology

891

223

View full text Add to dashboard Cite

show abstract

“…The activity of the DPNH-cv tochrome c reductase system (more than 200 x 10-4 micromoles cytochrome c/min x gm FW) in the supernatant is roughly ten times greater than that of the particulate enzyme and is of the same order of magnitude as the supernatant DPNH-attacking system described above. It is not inhibited by natant revealed that some of the DPNH-cytochrome c reductase is localized on the microsomes, which were obtained by centrifuging at 25,000 x g for 2 hours (International Refrigerated Centrifuge); this is also the case in liver homogenates (29 (14), is generally assumed to be a flavin-containing enzyme and is indicated by FP. The position of the Antimycin-A factor (AAF) is established by several lines of evidence: 1) Since DPNH oxidation is largely inhibited by AA, the factor must lie on the pathway between DPNH and oxygen; 2) Cytochrome c oxidation is insensitive to AA, so the factor is above the level of cytochrome c; 3) The almost complete AA-inhibition of succinic-cytochrome c reductase indicates that the factor lies between these two components; 4) The partial inhibition of DPNH-cytochrome c reductase by AA suggests a position between flavin and cytochrome c. The nature of this factor, which presumably corresponds to the BAL-sensitive Slater factor (25), is not definitely known, but it may be another heme-containing molecule or cytochrome (23).…”

Section: Miaterials and Methodsmentioning

confidence: 99%