scholarly journals An amino acid code for β-sheet packing structure

2014 ◽  
Vol 82 (9) ◽  
pp. 2128-2140 ◽  
Author(s):  
Hyun Joo ◽  
Jerry Tsai
2016 ◽  
Vol 110 (3) ◽  
pp. 538a-539a
Author(s):  
Hyun Joo ◽  
Keith J. Fraga ◽  
Jerry Tsai

2009 ◽  
Vol 30 (1) ◽  
pp. 319-332 ◽  
Author(s):  
James A. Toombs ◽  
Blake R. McCarty ◽  
Eric D. Ross

ABSTRACT Numerous prions (infectious proteins) have been identified in yeast that result from the conversion of soluble proteins into β-sheet-rich amyloid-like protein aggregates. Yeast prion formation is driven primarily by amino acid composition. However, yeast prion domains are generally lacking in the bulky hydrophobic residues most strongly associated with amyloid formation and are instead enriched in glutamines and asparagines. Glutamine/asparagine-rich domains are thought to be involved in both disease-related and beneficial amyloid formation. These domains are overrepresented in eukaryotic genomes, but predictive methods have not yet been developed to efficiently distinguish between prion and nonprion glutamine/asparagine-rich domains. We have developed a novel in vivo assay to quantitatively assess how composition affects prion formation. Using our results, we have defined the compositional features that promote prion formation, allowing us to accurately distinguish between glutamine/asparagine-rich domains that can form prion-like aggregates and those that cannot. Additionally, our results explain why traditional amyloid prediction algorithms fail to accurately predict amyloid formation by the glutamine/asparagine-rich yeast prion domains.


Life Sciences ◽  
1963 ◽  
Vol 2 (11) ◽  
pp. 845-851 ◽  
Author(s):  
P. Szafranski ◽  
J. Lutowicz ◽  
L. Puzynska
Keyword(s):  

2019 ◽  
Vol 20 (20) ◽  
pp. 5136 ◽  
Author(s):  
Mentes ◽  
Magyar ◽  
Fichó ◽  
Simon

Several intrinsically disordered proteins (IDPs) are capable to adopt stable structures without interacting with a folded partner. When the folding of all interacting partners happens at the same time, coupled with the interaction in a synergistic manner, the process is called Mutual Synergistic Folding (MSF). These complexes represent a discrete subset of IDPs. Recently, we collected information on their complexes and created the MFIB (Mutual Folding Induced by Binding) database. In a previous study, we compared homodimeric MSF complexes with homodimeric and monomeric globular proteins with similar amino acid sequence lengths. We concluded that MSF homodimers, compared to globular homodimeric proteins, have a greater solvent accessible main-chain surface area on the contact surface of the subunits, which becomes buried during dimerization. The main driving force of the folding is the mutual shielding of the water-accessible backbones, but the formation of further intermolecular interactions can also be relevant. In this paper, we will report analyses of heterodimeric MSF complexes. Our results indicate that the amino acid composition of the heterodimeric MSF monomer subunits slightly diverges from globular monomer proteins, while after dimerization, the amino acid composition of the overall MSF complexes becomes more similar to overall amino acid compositions of globular complexes. We found that inter-subunit interactions are strengthened, and additionally to the shielding of the solvent accessible backbone, other factors might play an important role in the stabilization of the heterodimeric structures, likewise energy gain resulting from the interaction of the two subunits with different amino acid compositions. We suggest that the shielding of the β-sheet backbones and the formation of a buried structural core along with the general strengthening of inter-subunit interactions together could be the driving forces of MSF protein structural ordering upon dimerization.


2011 ◽  
Vol 175-176 ◽  
pp. 176-180
Author(s):  
Hui Ying Wu ◽  
Bao Qi Zuo

Silk fibroin modified viscose fiber (SFVF) was a new fiber with silken handling and luster, which was produced via adding silk fibroin (SF) during the viscose process. In this paper, a series of testing had been done to study the structure and properties of SFVF. The amino acid content of SFVF was measured by HITACHI-835-50 amino acid tester. The morphology, structure, thermal and mechanical property of SFVF were characterized by SEM, FTIR, DSC and electronic strength tester. The results indicated that SFVF consisted of many kinds of amino acids compared with pure viscose fiber (VF) yarn. The results of SEM showed more continuous multi fine slots existed in the longitudinal section of SFVF than in that of VF, demonstrating that wet permeability and vapor transmission could be enhanced for the SFVF to certain extent. Results from FTIR indicated that the secondary structure of SFVF was mainly β-sheet and random coil, and its absorption peaks were 1616cm-1 and 1644 cm-1 respectively. The DSC curve shown the thermal decomposition temperature of SFVF was about 328.39°C, which was close to that of VF. It suggested that the SF modification had no obvious influence on thermal stability of VF. At last, the dry-strength and wet-strength of SFVF was close to that of VF. Therefore, the application of VF would be expanded with the SF modification.


Sign in / Sign up

Export Citation Format

Share Document