Ferritin as an exogenously derived yolk protein in Helisoma duryi (Mollusca: Pulmonata)

1986 ◽  
Vol 64 (12) ◽  
pp. 2678-2682 ◽  
Author(s):  
S. Miksys ◽  
A. S. M. Saleuddin
Keyword(s):  
Electron Microscopy ◽  
Digestive Gland ◽  
Storage Protein ◽  
Reproductive Activity ◽  
Iron Storage ◽  
Yolk Granules ◽  
X Ray ◽  
Helisoma Duryi ◽  
Pore Cells ◽  
Iron Storage Protein

The iron storage protein ferritin is identified as a yolk component in Helisoma duryi by histochemistry, electron microscopy, energy dispersive analytical x-ray analysis, and radioimmunoassay. It was found to accumulate in the yolk granules of maturing oocytes when they attained a diameter of 50 μm. Extraction of the protein and its estimation by radioimmunoassay in tissues from reproducing and reproductively inactive (virgin) snails suggest that ferritin is synthesized extragonadally and transported in the blood to maturing oocytes in the ovotestis. Ferritin was also found in the digestive gland and in the mantle, which contains pore cells. Mantle ferritin levels fluctuated with reproductive activity. The possibility that pore cells play a role in regulating vitellogenic ferritin is discussed.

The resolution of individual protein subunits in ferritin

1978 ◽  
Vol 36 (2) ◽  
pp. 182-183
Author(s):  
William H. Massover
Keyword(s):  
Electron Microscopy ◽  
Storage Protein ◽  
Quaternary Structure ◽  
Negative Staining ◽  
Variable Amount ◽  
X Ray Diffraction ◽  
Iron Storage ◽  
Protein Subunits ◽  
X Ray ◽  
Iron Storage Protein

The technique of negative staining has been of very great value for directly determining the quaternary structure of individual multimeric proteins and viruses. In this regard, the iron-storage protein,, ferritin, is a notable exception for not having had its subunits unambiguously resolved by negative staining. Each ferritin molecule (d= 120Å) has an outer shell of 24 protein subunits (MW= 18,500) surrounding a variable amount of mineralized iron; published x-ray diffraction studies have not yet defined individual monomers in the polymeric shell. Claims that single subunits have been visualized in ferritin by electron microscopy (e.g.,6) all appear to be of highly doubtful validity since the phase granularity of the dried stain and supporting film has the same dimension as the presumed subunits; apparent subunits are readily visualized in defocused images, but are no longer discernable when brought closer to exact focus.

scholarly journals M?ssbauer Effect In Ferritin

1966 ◽  
Vol 19 (4) ◽  
pp. 573 ◽  
Keyword(s):  
Electron Microscopy ◽  
Storage Protein ◽  
Iron Storage ◽  
Protein Shell ◽  
Iron Storage Protein

By Ferritin, the iron storage protein, is made up of a roughly spherical apo-protein shell enclosing a micelle of composition (FeOOH)s(FeO.OP03H2) (Granick and Hahn 1944; Farrant 1954). Electron microscopy (Farrant 1954; van Bruggen, Wiebenga, and Gruber 1960) showed that the micelle is approximately 55 A in diameter.

Polygonal profiles of ferritin molecules

1983 ◽  
Vol 41 ◽  
pp. 600-601
Author(s):  
William H. Massover
Keyword(s):  
Axial Ratio ◽  
X Ray Diffraction ◽  
Rhombic Dodecahedron ◽  
Apparent Contradiction ◽  
Iron Storage ◽  
X Ray ◽  
Hexagonal Shape ◽  
Axes Of Symmetry ◽  
Apparent Conflict ◽  
Iron Storage Protein

The molecular structure of the iron-storage protein, ferritin, is becoming known in ever finer detail. The 24 apoferritin subunits (MW ca. 20,000) have a 2:1 axial ratio and are polymerized with 4:3:2 symmetry to form an outer shell surrounding a variable amount of microcrystalline iron, Recent x-ray diffraction results indicate that the projected outline of the native molecule has a quasi-hexagonal shape when viewed down the 3-fold axes of symmetry, and a quasi-square shape when looking down the 4-fold axes. To date, no electron microscope study has reported observing anything other than circular profiles, which would indicate that ferritin is strictly spherical. The apparent conflict between the "hollow sphere" of electron microscopy (E.M.) and the "truncated rhombic dodecahedron" of x-ray diffraction could reflect the poorer effective resolution of E.M. coming from radiation damage, staining, drying, etc. The present study investigates the detailed shape of individual ferritin molecules in order to search for the predicted aspherical profiles and to interpret the nature of this apparent contradiction.

Analysis of Iron in Ferritin, the Iron-Storage Protein: A General Chemistry Experiment

1998 ◽  
Vol 75 (4) ◽  
pp. 437 ◽  
Author(s):  
Maureen J. Donlin ◽  
Regina F. Frey ◽  
Christopher Putnam ◽  
Jody Proctor ◽  
James K. Bashkin
Keyword(s):  
General Chemistry ◽  
Storage Protein ◽  
Protein A ◽  
Iron Storage ◽  
Chemistry Experiment ◽  
Iron Storage Protein

scholarly journals Preparation of platinum nanoparticles using iron(ii) as reductant and photosensitized H2 generation on an iron storage protein scaffold

RSC Advances ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 5551-5559
Author(s):  
Brenda S. Benavides ◽  
Silvano Valandro ◽  
Donald M. Kurtz
Keyword(s):  
Heavy Chain ◽  
Platinum Nanoparticles ◽  
Storage Protein ◽  
Iron Storage ◽  
Protein Scaffold ◽  
H2 Generation ◽  
Iron Storage Protein

An assembly of platinum nanoparticles produced by Fe(ii) reduction of Pt(ii) and stabilized by human heavy chain ferritin's native catalysis of Fe(ii)(aq) autoxidation functions as an efficient photosensitized H2 evolution catalyst.

scholarly journals Ferritin does not accumulate iron oxidized by caeruloplasmin

1995 ◽  
Vol 305 (1) ◽  
pp. 21-23 ◽  
Author(s):  
A Treffry ◽  
D Gelvan ◽  
A M Konijn ◽  
P M Harrison
Keyword(s):  
Dissolved Oxygen ◽  
Storage Protein ◽  
Iron Oxidation ◽  
Primary Effect ◽  
Significant Extent ◽  
Iron Storage ◽  
Horse Spleen Ferritin ◽  
Iron Storage Protein

Ferritin is an iron-storage protein ubiquitous in mammals, plants and bacteria. It can be reconstituted, in vitro, from the apoprotein and Fe(II) salts in the presence of dissolved oxygen. Recently it has been reported that caeruloplasmin can facilitate apoferritin reconstitution and that iron oxidized by caeruloplasmin is sequestered within the ferritin shell. Here we show that the primary effect of adding caeruloplasmin to horse spleen ferritin during reconstitution is the competition between the two molecules for the iron. This competition results in overall increased rates of iron oxidation and a mixture of products, namely iron-containing ferritin and iron hydroxy polymers attached to caeruloplasmin. Iron oxidized by caeruloplasmin is not incorporated, to any significant extent, into horse spleen ferritin.

Ferritin as an iron-storage protein: mechanisms of iron uptake

1986 ◽  
Vol 27 (4) ◽  
pp. 287-293 ◽  
Author(s):  
Pauline M. Harrison ◽  
Amyra Treffry ◽  
Terence H. Lilley
Keyword(s):  
Storage Protein ◽  
Iron Uptake ◽  
Iron Storage ◽  
Iron Storage Protein

Increased Expression of Ferritin, an Iron-storage Protein, in Specific Regions of the Parahippocampal Cortex of Epileptic Rats

Epilepsia ◽  
2005 ◽  
Vol 46 (9) ◽  
pp. 1371-1379 ◽  
Author(s):  
Jan A. Gorter ◽  
Ana R.M. Mesquita ◽  
Erwin A. van Vliet ◽  
Fernando H. Lopes da Silva ◽  
Eleonora Aronica
Keyword(s):  
Storage Protein ◽  
Iron Storage ◽  
Parahippocampal Cortex ◽  
Iron Storage Protein
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