1
|
Malik A, Khan JM, Alhomida AS, Ola MS, Alokail MS, Khan MS, Alenad AM, Altwaijry N, Alafaleq NO, Odeibat H. Agitation does not induce fibrillation in reduced hen egg-white lysozyme at physiological temperature and pH. J Mol Recognit 2023; 36:e3009. [PMID: 36841950 DOI: 10.1002/jmr.3009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 02/21/2023] [Accepted: 02/22/2023] [Indexed: 02/27/2023]
Abstract
Several proteins and peptides tend to form an amyloid fibril, causing a range of unrelated diseases, from neurodegenerative to certain types of cancer. In the native state, these proteins are folded and soluble. However, these proteins acquired β-sheet amyloid fibril due to unfolding and aggregation. The conversion mechanism from well-folded soluble into amorphous or amyloid fibril is not well understood yet. Here, we induced unfolding and aggregation of hen egg-white lysozyme (HEWL) by reducing agent dithiothreitol and applied mechanical sheering force by constant shaking (1000 rpm) on the thermostat for 7 days. Our turbidity results showed that reduced HEWL rapidly formed aggregates, and a plateau was attained in nearly 5 h of incubation in both shaking and non-shaking conditions. The turbidity was lower in the shaking condition than in the non-shaking condition. The thioflavin T binding and transmission electron micrographs showed that reduced HEWL formed amorphous aggregates in both conditions. Far-UV circular dichroism results showed that reduced HEWL lost nearly all alpha-helical structure, and β-sheet secondary structure was not formed in both conditions. All the spectroscopic and microscopic results showed that reduced HEWL formed amorphous aggregates under both conditions.
Collapse
Affiliation(s)
- Ajamaluddin Malik
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Javed Masood Khan
- Department of Food Science and Nutrition, Faculty of Food and Agricultural Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Abdullah S Alhomida
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Mohammad Shamsul Ola
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Majed S Alokail
- Protein Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Mohd Shahnawaz Khan
- Protein Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Amal M Alenad
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Nojood Altwaijry
- Protein Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Nouf Omar Alafaleq
- Protein Research Chair, Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Hamza Odeibat
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| |
Collapse
|