Understanding fibrillogenesis at a molecular level requires detailed structural characterization of amyloid fibrils. The combination of deep UV resonance Raman (DUVRR) spectroscopy and post mortem hydrogen-deuterium exchange (HX) was utilized for probing parallel vs antiparallel beta-sheets in fibrils prepared from full-length Abeta(1-40) and Abeta(34-42) peptides, respectively. Using previously published structural data based on solid-state NMR analysis, we verified the applicability of Asher's approach for the quantitative characterization of peptide conformation in the Abeta(1-40) fibril core. We found that the conformation of the parallel beta-sheet in the Abeta(1-40) fibril core is atypical for globular proteins, while in contrast, the antiparallel beta-sheet in Abeta(32-42) fibrils is a common structure in globular proteins. In contrast to the case for globular proteins, the conformations of parallel and antiparallel beta-sheets in Abeta fibril cores are substantially different, and their differences can be distinguished by DUVRR spectroscopy.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/ja909074j | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Phase transitions in chromatin: Mesoscopic and mean-field approaches.
J Chem Phys
January 2025
CNRS, Laboratoire PHENIX (Physicochimie des Electrolytes et Nanosystèmes Interfaciaux), Sorbonne Université, 4 Place Jussieu, 75005 Paris, France.
By means of a minimal physical model, we investigate the interplay of two phase transitions at play in chromatin organization: (1) liquid-liquid phase separation within the fluid solvating chromatin, resulting in the formation of biocondensates; and (2) the coil-globule crossover of the chromatin fiber, which drives the condensation or extension of the chain. In our model, a species representing a domain of chromatin is embedded in a binary fluid. This fluid phase separates to form a droplet rich in a macromolecule (B).
View Article and Find Full Text PDFCG modeling of nucleosome arrays reveals the salt-dependent chromatin fiber conformational variability.
J Chem Phys
January 2025
School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore.
Eukaryotic DNA is packaged in the cell nucleus into chromatin, composed of arrays of DNA-histone protein octamer complexes, the nucleosomes. Over the past decade, it has become clear that chromatin structure in vivo is not a hierarchy of well-organized folded nucleosome fibers but displays considerable conformational variability and heterogeneity. In vitro and in vivo studies, as well as computational modeling, have revealed that attractive nucleosome-nucleosome interaction with an essential role of nucleosome stacking defines chromatin compaction.
View Article and Find Full Text PDFEssential Role of Cortactin in Myogenic Differentiation: Regulating Actin Dynamics and Myocardin-Related Transcription Factor A-Serum Response Factor (MRTFA-SRF) Signaling.
Int J Mol Sci
December 2024
Department of Biochemistry, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Republic of Korea.
Cortactin (CTTN) is an actin-binding protein regulating actin polymerization and stabilization, which are vital processes for maintaining skeletal muscle homeostasis. Despite the established function of CTTN in actin cytoskeletal dynamics, its role in the myogenic differentiation of progenitor cells remains largely unexplored. In this study, we investigated the role of CTTN in the myogenic differentiation of C2C12 myoblasts by analyzing its effects on actin cytoskeletal remodeling, myocardin-related transcription factor A (MRTFA) nuclear translocation, serum response factor (SRF) activation, expression of myogenic transcription factors, and myotube formation.
View Article and Find Full Text PDFTranscriptome and Gene Expression Analysis Revealed : A Potential New Marker for Somatic Embryogenesis in Common Centaury ( Rafn.).
Int J Mol Sci
December 2024
Department of Plant Physiology, Institute for Biological Research "Siniša Stanković"-National Institute of Republic of Serbia, University of Belgrade, Bulevar Despota Stefana 142, 11108 Belgrade, Serbia.
Rafn. is a medicinal plant used as a model for studying plant developmental processes due to its developmental plasticity and ease of manipulation in vitro. Identifying the genes involved in its organogenesis and somatic embryogenesis (SE) is the first step toward unraveling the molecular mechanisms underlying its morphogenic plasticity.
View Article and Find Full Text PDFSurface interactions of gelatin-sourced carbon quantum dots with a model globular protein: insights into carbon-based nanomaterials and biological systems.
Nanoscale Adv
December 2024
The Department of Chemistry & Biochemistry, The University of Texas at El Paso 500 W. University Ave. El Paso TX 79968 USA
Carbon nanomaterials (CNMs), such as carbon nanotubes (CNTs), graphene quantum dots (GQDs), and carbon quantum dots (CQDs), are prevalent in biological systems and have been widely utilized in applications like environmental sensing and biomedical fields. While their presence in human matrices is projected to increase, the interfacial interactions between carbon-based nanoscopic platforms and biomolecular systems continue to remain underexplored. In this study, we investigated the effect of gelatin-sourced CQDs on the globular milk protein beta-lactoglobulin (BLG).
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!