Aspartic acid (Asp) and asparagine (Asn) are vulnerable amino acids. One-electron addition or withdrawal reactions initiate many deleterious processes involving these amino acids. To study these redox processes we have irradiated by gamma-rays asparagine or aspartic acid in the solid state. The nature of the resulting free radicals was determined by electron paramagnetic resonance (EPR) and by calculations using DFT methods in various environments. Reactions initiated by electron transfer are different for both amino acids: Asn anion loses hydrogen atom whereas the cation undergoes decarboxylation. Conversely, Asp cation loses hydrogen atom from amine group, which triggers decarboxylation.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.bpc.2006.06.017 | DOI Listing |
Int J Syst Evol Microbiol
January 2025
Department of Biochemistry and Microbiology, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok 10330, Thailand.
A Gram-stain-positive, facultatively anaerobic, rod-shaped strain, designated SPB1-3, was isolated from tree bark. This strain exhibited heterofermentative production of dl-lactic acid from glucose. Optimal growth was observed at 25-40 °C, pH 4.
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2025
Chemistry Division, Bhabha Atomic Research Centre, Mumbai, 400085, India.
The present study focuses on designing mutant peptides derived from the lanthanide binding tag (LBT) to enhance selectivity for trivalent actinide (An) ions over lanthanide (Ln) metal ions (M). The LBT is a short peptide consisting of only 17 amino acids, and is known for its high affinity towards Ln. LBT was modified by substituting hard-donor ligands like asparagine (ASN or N) and aspartic acid (ASP or D) with softer ligand cysteine (CYS or C) to create four mutant peptides: M-LBT (wild-type), M-N103C, M-D105C, and M-N103C-D105C.
View Article and Find Full Text PDFInt J Nanomedicine
January 2025
Department of Ultrasound, The second People's Hospital of Shenzhen, The First Affiliated Hospital of Shenzhen University, Shenzhen, 518061, People's Republic of China.
Purpose: Osteosarcoma is the most common primary malignant tumor of the bone. However, there is a lack of effective means for early diagnosis due to the heterogeneity of tumors and the complexity of tumor microenvironment. αvβ3 integrin, a crucial role in the growth and spread of tumors, is not only an effective biomarker for cancer angiogenesis, but also highly expressed in many tumor cells.
View Article and Find Full Text PDFCureus
December 2024
Internal Medicine, National Hospital of Sri Lanka, Colombo, LKA.
Hereditary hemochromatosis occurs due to genetic mutations, namely, cysteine-to-tyrosine substitution at amino acid 282 (C282Y) and histidine-to-aspartic acid substitution at 63 (H63D) mutations. The role of H63D mutation in hemochromatosis is less clear, and its penetrance is low even in homozygotes. Therefore, iron overload in H63D heterozygotes is extremely rare and scarcely reported.
View Article and Find Full Text PDFBiofilm
June 2025
CEB - Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.
Antibiotics are central to managing airway infections in cystic fibrosis (CF), yet current treatments often fail due to the presence of biofilms, settling down the need for seeking therapies targeting biofilms. This study aimed to investigate the antibiofilm activity of aspartic acid and its potential as an adjuvant to tobramycin against biofilms formed by mucoid and small colony variant (SCV) tobramycin tolerant strain. We assessed the effect of aspartic acid on both surface-attached and suspended biofilms within CF artificial mucus and investigated the synergistic impact of combining it with non-lethal tobramycin concentrations.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!