The copper(II) binding features of the APP(145-155) and APP(145-157) fragments of the amyloid precursor protein, Ac-Glu-Thr-His-Leu-His-Trp-His-Thr-Val-Ala-Lys-NH2 and Ac-Glu-Thr-His-Leu-His-Trp-His-Thr-Val-Ala-Lys-Glu-Thr-NH2 were studied by NMR spectroscopy and NMR findings were supported by UV-vis, CD and EPR spectra. Potentiometric measurements were performed only for the more soluble Ac-Glu-Thr-His-Leu-His-Trp-His-Thr-Val-Ala-Lys-Glu-Thr-NH2 peptide fragment. The following was shown: (i) the imidazole rings of all the three His residues are involved in metal coordination; (ii) metal binding induces ionisation of Leu-148 and His-149 amide nitrogens that complete the donor set to copper(II) in the species dominant at neutral pH; (iii) the unusual coordination scheme of the His-Xxx-His-Xxx-His consensus sequence justifies the high specificity for Cu(II) when compared to SOD-like or albumin-like peptides or even in amyloid Abeta fragments. The present findings may represent the key for interpreting the observed requirement of His residues conservation for the redox cycling between Cu(II) and Cu(I) by soluble APP.

Download full-text PDF

Source
http://dx.doi.org/10.1039/b312411hDOI Listing

Publication Analysis

Top Keywords

amyloid precursor
8
precursor protein
8
identification novel
4
novel high
4
high affinity
4
affinity copper
4
copper binding
4
binding site
4
site app145-155
4
app145-155 fragment
4

Similar Publications

Biomarkers.

Alzheimers Dement

December 2024

Fleni, Buenos Aires, Argentina.

Background: Down Syndrome (DS) is the most common genetic form of intellectual disability. In recent years, there has been a significant increase in the life expectancy of individuals with DS, currently reaching the age of 60 or over. However, it has been observed that as of age 40, these individuals experience higher risk of developing dementia, and almost all of them exhibit histopathological characteristics of Alzheimer's disease (AD) in their brains.

View Article and Find Full Text PDF

Biomarkers.

Alzheimers Dement

December 2024

Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division of Clinical Geriatrics, Karolinska Institutet, Stockholm, Sweden.

Background: [F]FDG PET is essential since it allows us to differentiate between different dementia disorders/types, revealing distinct neurodegenerative patterns in those predisposed to the condition. Individuals with Autosomal Dominant Alzheimer's Disease (ADAD) have a predictable age of onset, enabling the study of cognitive and pathological changes before clinical manifestation. Our objective was to investigate temporal course and regional links between cognition and glucose metabolism as a measure of early synaptic impairment in ADAD.

View Article and Find Full Text PDF

Background: Older vervet monkeys are an excellent model for studying age-associated Aβ deposition; however, they have high proportions of low-affinity Aβ sites compared to human brains. Commonly used Aβ PET radiotracers are most useful in detecting high affinity Aβ fibrils. Measuring real-time levels of low affinity Aβ fibrils through PET provides critical information of early AD progression.

View Article and Find Full Text PDF

Background: Trisomy 21 in Down syndrome (DS) is associated with an earlier accumulation of beta-amyloid (Aβ) plaques and a higher rate of Alzheimer's Disease due to the triplication of the amyloid precursor protein gene. In this study we compare accumulation rates of Aβ measured with [C-11]PiB PET between large longitudinal cohorts of DS and neurotypical (NT) participants at a single site.

Methods: Participants imaged at the University of Wisconsin with ≥2 PiB scans and ≥2 years between scans were included in this study.

View Article and Find Full Text PDF

Background: The Down Syndrome (DS), also referred to as trisomy of chromosome 21, is a prevalent cause of intellectual disability and also contributes to the acceleration of aging, among other developmental and health concerns. Certain pathological characteristics shared by DS and Alzheimer's Disease (AD) indicate similar commonalities. This study aims to unravel the relationship between the canonical Wnt/pathway, the amyloid precursor protein processing, the telomere shortening in DS individuals.

View Article and Find Full Text PDF

Want 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!