Due to chemical exchange, the mobility of histidine (His) side chains of proteins is typically difficult to analyze by NMR spectroscopy. Using an NMR approach that is uninfluenced by chemical exchange, we investigated internal motions of the His imidazole NH groups that directly interact with DNA phosphates in the Egr-1 zinc-finger-DNA complex. In this approach, the transverse and longitudinal cross-correlation rates for N chemical shift anisotropy and N-H dipole-dipole relaxation interference were analyzed together with N longitudinal relaxation rates and heteronuclear Overhauser effect data at two magnetic field strengths. We found that the zinc-coordinating His side chains directly interacting with DNA phosphates are strongly restricted in mobility. This makes a contrast to the arginine and lysine side chains that retain high mobility despite their interactions with DNA phosphates in the same complex. The entropic effects of side-chain mobility on the molecular association are discussed.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6501774 | PMC |
http://dx.doi.org/10.1021/acs.jpcb.9b03132 | DOI Listing |
RSC Chem Biol
January 2025
Department of Immunology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine Kamigyo-ku 465 Kajii-cho Kyoto 602-8566 Japan
A multiomic study of the structural characteristics of type A and B influenza viruses by means of highly spectrally resolved Raman spectroscopy is presented. Three virus strains, A H1N1, A H3N2, and B98, were selected because of their known structural variety and because they have co-circulated with variable relative prevalence within the human population since the re-emergence of the H1N1 subtype in 1977. Raman signatures of protein side chains tyrosine, tryptophan, and histidine revealed unequivocal and consistent differences for pH characteristics at the virion surface, while different conformations of two C-S bond configurations in and methionine rotamers provided distinct low-wavenumber fingerprints for different virus lineages/subtypes.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Department of Chemistry, Rutgers University, Camden, NJ, United States of America; Center for Computational and Integrative Biology, Rutgers University, Camden, NJ, United States of America. Electronic address:
Ion transport in solid polymer electrolytes is crucial for applications like energy conversion and storage, as well as carbon dioxide capture. However, most of the materials studied in this area are petroleum-based. Natural materials (biopolymers) have the potential to act as alternatives to petroleum-based products and, when derived with ionic liquid (IL) functionalities, present a sustainable alternative for conductive materials by offering tunable morphological, thermal, and mechanical properties.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
College of Information Science and Engineering, Northeastern University, China.
Protein-protein interactions (PPI) are crucial for understanding numerous biological processes and pathogenic mechanisms. Identifying interaction sites is essential for biomedical research and targeted drug development. Compared to experimental methods, accurate computational approaches for protein-protein interaction sites (PPIS) prediction can save significant time and costs.
View Article and Find Full Text PDFFree Radic Biol Med
January 2025
Department of Life Science, Ewha Womans University, Seoul 03760, Republic of Korea. Electronic address:
Epidithio-diketopiperazine (ETP) compound is the family of natural fungal metabolites that are known to exert diverse biological effects, such as immunosuppression and anti-cancer activity, in higher animals. However, an enzyme-like catalytic activity or function of the ETP derivatives has not been reported. Here, we report the generation of novel thiol peroxidase mimetics that possess peroxide-reducing activity through strategic derivatization of the core ETP ring structure.
View Article and Find Full Text PDFBiomacromolecules
January 2025
Department of Biological Sciences and Bioengineering, Inha University, 100 Inha-ro, Michuhol-gu, Incheon 22212, Republic of Korea.
Engineered natural killer (NK) cells eliminate cancer cells by overexpressing a chimeric antigen receptor, producing highly efficient and safe NK cell therapies. This study investigated the polyplex formulation for the fusion protein GreenLantern-natural killer group 2D (NKG2D) mRNA to evaluate its delivery efficacy into NK cells, wherein NKG2D on the surface of NK cells recognized its counterpart NKG2D ligands on cancer cells. Amphiphilic polyaspartamide derivatives Chol-PAsp(DET/CHE) were prepared by adding cyclohexylethylamine (CHE) and diethylenetriamine (DET) in the side chains and cholesterol (Chol) at the α-terminus to enhance endosomal escapability and optimize hydrophobicity.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!