Cationic gemini surfactant stimulates amyloid fibril formation in bovine liver catalase at physiological pH. A biophysical study

Surfactant molecules stimulate amyloid fibrillation and conformational switching in proteins but the mechanisms by which they accomplish these effects are unclear.

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Cationic gemini surfactant (16-4-16) interact electrostatically with anionic plant lectin and facilitates amyloid fibril formation at neutral pH

Colloids and Surfaces A Physicochemical and Engineering Aspects ◽

10.1016/j.colsurfa.2017.03.048 ◽

2017 ◽

Vol 522 ◽

pp. 494-502 ◽

Cited By ~ 18

Author(s):

Javed Masood Khan ◽

Mohd. Shahnawaz Khan ◽

Atiyatul Qadeer ◽

Mohammad A. Alsenaidy ◽

Anwar Ahmed ◽

...

Keyword(s):

Gemini Surfactant ◽

Amyloid Fibril ◽

Fibril Formation ◽

Plant Lectin ◽

Cationic Gemini Surfactant ◽

Neutral Ph ◽

Amyloid Fibril Formation

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Antioxidants From the Class of Polyphenols, NAC and Vitamin C Act Differently on Amyloid Fibril Formation by Two Human Cystatins: Stefin B and Cystatin C.

10.20944/preprints202010.0274.v1 ◽

2020 ◽

Author(s):

Alma Jahic Mujkic ◽

Samra Hasanbasic ◽

Magda Tušek Žnidarič ◽

Selma Berbic ◽

Eva Zerovnik

Keyword(s):

Vitamin C ◽

Cystatin C ◽

Amyloid Fibril ◽

Synergistic Effects ◽

Fibril Formation ◽

Homologous Proteins ◽

Amyloid Fibril Formation ◽

Transmission Electron ◽

Amyloid Fibrillation ◽

Anti Oxidant

We compare the effect on amyloid fibril formation by two homologous proteins from the family of cystatins, human stefin B (stB) and cystatin C (cysC) in presence of 3 polyphenols: curcumin, resveratrol and quercetin and 2 non-phenolic anti-oxidants: vitamin C (VitC) and N-acetyl cystein (NAC). Some of the experimental data have already been presented, here we compare, further discuss and highlight the results. The amyloid fibril formation was followed by ThT fluorescence and transmission electron microscopy. Inhibitory effects on amyloid fibrillation reaction depended on anti-oxidant class and concentration. The fact that different effect of polyphenols was observed with the two cystatins; Cur acted inhibitory on stB but not on cysC fibril formation, could be explained if the 3 polyphenols would not bind to the same binding site in the fibrils core. Other differences are pointed out and discussed. Synergistic effects of VitC and chosen polyphenols on amyloid fibrilllation of human stB have been explored and are reported here for the first time.

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Immunocytochemical Localization of Amyloid Protein AA in the “Dense Fibrillar Inclusions” of the Reticuloendothelical Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079632 ◽

1977 ◽

Vol 35 ◽

pp. 438-439

Author(s):

T. Shirahama ◽

M. Skinner ◽

A.S. Cohen

Keyword(s):

Amyloid Fibril ◽

Close Association ◽

Gel Filtration ◽

Fibril Formation ◽

Amyloid Protein ◽

Electron Microscopic ◽

Amyloid Deposits ◽

Amyloid Fibril Formation ◽

Electron Microscopic Technique ◽

Lysosomal System

A1thought the mechanisms of amyloidogenesis have not been entirely clarified, proteolysis of the parent proteins may be one of the important steps in the amyloid fibril formation. Recently, we reported that "dense fibrillar inclusions" (DFI), which had the characteristics of lysosomes and contained organized fibrillar profiles as well, were observed in the reticuloendothelial cells in close association with the foci of new amyloid deposits. We considered the findings as evidence for the involvement of lysosomal system in amyloid fibril formation (l). In the present study, we attempted to determine the identity of the contents of the DFI by the use of antisera against the amyloid protein (AA) and an immuno-electron microscopic technique.Amyloidosis was induced in CBA/J mice by daily injections of casein (l). AA was isolated from amyloid-laden spleens by gel filtration and antibody to it was produced in rabbits (2). For immunocytochemistry, the unlabeled antibody enzyme method (3) was employed.

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