Inhibition of Protein Fibrillation by Hydrogen Sulfide [chapter]

Manuel F. Rosario-Alomar, Tatiana Quiñones-Ruiz, Dmitry Kurouski, Valentin Sereda, Eduardo DeBarros-Ferreira, Lorraine De Jesús-Kim, Samuel Hernández-Rivera, Dmitri V. Zagorevski, Leishla M. Cruz-Collazo, Igor K. Lednev, Juan López-Garriga
2019 Amyloidosis [Working Title]  
Amyloid fibrils are misfolded proteins, which are often associated with various neurodegenerative diseases such as Alzheimer's. The amount of hydrogen sulfide (H 2 S) is known to be reduced in the brain tissue of people diagnosed with Alzheimer's disease relative to that of healthy individuals. Hen Egg-White Lysozyme (HEWL) forms typical β-sheet-rich fibrils during 70 minutes at low pH and high temperatures. These results are consistent with the ThT findings that β-sheets structure is also
more » ... ucture is also present in myoglobin (Mb), and hemoglobin (Hb) in the presence of 45% TFE. The addition of H 2 S in the process completely inhibits the formation of amyloid fibrils in HEWL, Mb, and Hb as revealed by several spectroscopic techniques. Non-resonance Raman bands corresponding to disulfide (RSSR) vibrational modes in the 550-500 cm -1 spectral range decreases in intensity and is accompanied by the appearance of a new 490 cm -1 band assigned to the trisulfide group (RSSSR). Intrinsic tryptophan fluorescence shows a partial denaturation of HEWL containing trisulfide bonds. Overall, the Mb and Hb result ties excellent with the HEWL data showing that the presence of H 2 S during these proteins fibrillation processes protects the α-helical protein structures, preventing the formation of amyloids in these different proteins moieties.
doi:10.5772/intechopen.86221 fatcat:4sc7eukjcfd7dcyeqqzupgazr4