Survival of native structure and biological activity in fibronectin pasteurized in the presence of sucrose

Many unfolded polypeptides are capable of refolding into their native structure upon the removal of the denaturant. However, the folding of the mature protein during renaturation does not accurately reflect the folding process of nascent proteins in the interior of the cell. This view resulted from the discovery of molecular chaperones known to modulate protein folding. Recent publications discussing the possible role and mechanisms of chaperone action suggest that folding in vivo may be a posttranslational process. Here we discuss data that indicate the final native structure and biological activity can be attainted by nascent protein on the ribosome, thus supporting the cotranslational folding hypothesis.Key words: nacent peptide, globin, luciferase, folding.

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Regeneration of native structure and biological activity by air oxidation of the reduced bovine trypsin inhibitor (Kunitz)*

International journal of peptide & protein research ◽

10.1111/j.1399-3011.1984.tb00963.x ◽

2009 ◽

Vol 24 (4) ◽

pp. 359-366 ◽

Cited By ~ 2

Author(s):

LAURA BIONDI ◽

BRUNO FILIPPI ◽

FERNANDO FILIRA ◽

MARILENA TOLAZZI ◽

RANIERO ROCCHI

Keyword(s):

Biological Activity ◽

Trypsin Inhibitor ◽

Native Structure ◽

Air Oxidation ◽

Bovine Trypsin

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The Complex Phosphorylation Patterns that Regulate the Activity of Hsp70 and Its Cochaperones

International Journal of Molecular Sciences ◽

10.3390/ijms20174122 ◽

2019 ◽

Vol 20 (17) ◽

pp. 4122 ◽

Cited By ~ 7

Author(s):

Velasco ◽

Dublang ◽

Moro ◽

Muga

Keyword(s):

Biological Activity ◽

Molecular Chaperones ◽

Acute Stress ◽

Phosphorylation Sites ◽

Native Structure ◽

Post Translational Modifications ◽

Cytotoxic Cells ◽

Functional Consequences ◽

Client Proteins ◽

Human Hsp70

Proteins must fold into their native structure and maintain it during their lifespan to display the desired activity. To ensure proper folding and stability, and avoid generation of misfolded conformations that can be potentially cytotoxic, cells synthesize a wide variety of molecular chaperones that assist folding of other proteins and avoid their aggregation, which unfortunately is unavoidable under acute stress conditions. A protein machinery in metazoa, composed of representatives of the Hsp70, Hsp40, and Hsp110 chaperone families, can reactivate protein aggregates. We revised herein the phosphorylation sites found so far in members of these chaperone families and the functional consequences associated with some of them. We also discuss how phosphorylation might regulate the chaperone activity and the interaction of human Hsp70 with its accessory and client proteins. Finally, we present the information that would be necessary to decrypt the effect that post-translational modifications, and especially phosphorylation, could have on the biological activity of the Hsp70 system, known as the “chaperone code”.

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Regeneration of native structure and biological activity by air oxidation of reduced pancreatic secretory trypsin inhibitor and Des-Thr-Ser-Pro-Gln-Arg-inhibitor

FEBS Letters ◽

10.1016/0014-5793(70)80530-0 ◽

1970 ◽

Vol 11 (3) ◽

pp. 209-212 ◽

Cited By ~ 12

Author(s):

H. Tschesche ◽

G. Haenisch

Keyword(s):

Biological Activity ◽

Trypsin Inhibitor ◽

Native Structure ◽

Air Oxidation ◽

Pancreatic Secretory Trypsin Inhibitor

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Virus-Like Particles in a Human Breast Cancer: Structural Similarity to Previously Reported Particles

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072332 ◽

1973 ◽

Vol 31 ◽

pp. 378-379

Author(s):

G. Kasnic ◽

S. E. Stewart ◽

C. Urbanski

Keyword(s):

Breast Cancer ◽

Biological Activity ◽

Human Breast Cancer ◽

Osteogenic Sarcoma ◽

Human Tumor ◽

Structural Similarity ◽

Cell Tumor ◽

Human Breast ◽

Human Tumor Cell ◽

Type Particle

We have reported the maturation of an intracisternal A-type particle in murine plasma cell tumor cultures and three human tumor cell cultures (rhabdomyosarcoma, lung adenocarcinoma, and osteogenic sarcoma) after IUDR-DMSO activation. In all of these studies the A-type particle seems to develop into a form with an electron dense nucleoid, presumably mature, which is also intracisternal. A similar intracisternal A-type particle has been described in leukemic guinea pigs. Although no biological activity has yet been demonstrated for these particles, on morphologic grounds, and by the manner in which they develop within the cell, they may represent members of the same family of viruses.

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The native structure of the eukaryotic ribosome

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075890 ◽

1983 ◽

Vol 41 ◽

pp. 432-433

Author(s):

R.A. Milligan ◽

P.N.T. Unwin

Keyword(s):

Ribosomal Proteins ◽

Crystal Form ◽

Native Structure ◽

X Ray Diffraction ◽

Eukaryotic Ribosome ◽

Vitro Analysis ◽

In Vitro Analysis ◽

Resolution Structure ◽

Stable Unit

A detailed understanding of the mechanism of protein synthesis will ultimately depend on knowledge of the native structure of the ribosome. Towards this end we have investigated the low resolution structure of the eukaryotic ribosome embedded in frozen buffer, making use of a system in which the ribosomes crystallize naturally.The ribosomes in the cells of early chicken embryos form crystalline arrays when the embryos are cooled at 4°C. We have developed methods to isolate the stable unit of these arrays, the ribosome tetramer, and have determined conditions for the growth of two-dimensional crystals in vitro, Analysis of the proteins in the crystals by 2-D gel electrophoresis demonstrates the presence of all ribosomal proteins normally found in polysomes. There are in addition, four proteins which may facilitate crystallization. The crystals are built from two oppositely facing P4 layers and the predominant crystal form, accounting for >80% of the crystals, has the tetragonal space group P4212, X-ray diffraction of crystal pellets demonstrates that crystalline order extends to ~ 60Å.

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Effects of Vincristine on Endothelial Microtubules in the Spinal Cord

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100090270 ◽

1976 ◽

Vol 34 ◽

pp. 58-59

Author(s):

John L. Beggs ◽

John D. Waggener ◽

Wanda Miller

Keyword(s):

Spinal Cord ◽

Biological Activity ◽

Horseradish Peroxidase ◽

Transport Mechanism ◽

Vasogenic Edema ◽

Vesicular Transport ◽

Close Proximity

Microtubules (MT) are versatile organelles participating in a wide variety of biological activity. MT involvement in the movement and transport of cytoplasmic components has been well documented. In the course of our study on trauma-induced vasogenic edema in the spinal cord we have concluded that endothelial vesicles contribute to the edema process. Using horseradish peroxidase as a vascular tracer, labeled endothelial vesicles were present in all situations expected if a vesicular transport mechanism was in operation. Frequently,labeled vesicles coalesced to form channels that appeared to traverse the endothelium. The presence of MT in close proximity to labeled vesicles sugg ested that MT may play a role in vesicular activity.

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