Cold-regulated (COR) 15A is an intrinsically disordered protein (IDP) from important for freezing tolerance. During freezing-induced cellular dehydration, COR15A transitions from a disordered to mostly α-helical structure. We tested whether mutations that increase the helicity of COR15A also increase its protective function. Conserved glycine residues were identified and mutated to alanine. Nuclear magnetic resonance (NMR) spectroscopy was used to identify residue-specific changes in helicity for wildtype (WT) COR15A and the mutants. Circular dichroism (CD) spectroscopy was used to monitor the coil⁻helix transition in response to increasing concentrations of trifluoroethanol (TFE) and ethylene glycol. The impact of the COR15A mutants on the stability of model membranes during a freeze⁻thaw cycle was investigated by fluorescence spectroscopy. The results of these experiments showed the mutants had a higher content of α-helical structure and the increased α-helicity improved membrane stabilization during freezing. Comparison of the TFE- and ethylene glycol-induced coil⁻helix transitions support our conclusion that increasing the transient helicity of COR15A in aqueous solution increases its ability to stabilize membranes during freezing. Altogether, our results suggest the conserved glycine residues are important for maintaining the disordered structure of COR15A but are also compatible with the formation of α-helical structure during freezing induced dehydration.
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http://dx.doi.org/10.3390/biom9030084 | DOI Listing |
Acc Chem Res
January 2025
School of Engineering, Westlake University, Hangzhou 310024, Zhejiang Province, China.
ConspectusCovalent triazine frameworks (CTFs) are a novel class of nitrogen-rich conjugated porous organic materials constructed by robust and functional triazine linkages, which possess unique structures and excellent physicochemical properties. They have demonstrated broad application prospects in gas/molecular adsorption and separation, catalysis, energy conversion and storage, etc. In particular, crystalline CTFs with well-defined periodic molecular network structures and regular pore channels can maximize the utilization of the features of CTFs and promote a deep understanding of the structure-property relationship.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China.
Effective delivery and controlled release of metallo-prodrugs with sustained activation and rapid response feed the needs of precise medicine in metal chemotherapeutics. However, gold-based anticancer drugs often suffer from detoxification binding and extracellular transfer by sulfur-containing peptides. To address this challenge, we integrate a thiol-activated prodrug strategy of newly prepared hypercoordinated carbon-centered gold(I) clusters (HCGCs) with their photosensitization character to augment the mitochondrial release of Au(I) in tumors.
View Article and Find Full Text PDFNano Lett
January 2025
Key Lab for the Physics and Chemistry of Nanodevices and Center for Carbon-based Electronics, School of Electronics, Peking University, Beijing 100871, China.
One-time programmable (OTP) memory is an essential component in chips, which has extremely high security to protect the stored critical information from being altered. However, traditional OTP memory based on the thermal breakdown of the dielectric has a large programming current, which leads to high power consumption. Here, we report a gate tunneling-induced "cold" breakdown phenomenon in carbon nanotube (CNT) field-effect transistors, and based on this we construct a "cold" fuse (C-fuse) memory where applying a mild gate voltage can break down the CNT channel without damaging the gate dielectric.
View Article and Find Full Text PDFBrief Bioinform
November 2024
School of Engineering, Westlake University, No. 600 Dunyu Road, 310030 Zhejiang, P.R. China.
Single-cell RNA sequencing (scRNA-seq) offers remarkable insights into cellular development and differentiation by capturing the gene expression profiles of individual cells. The role of dimensionality reduction and visualization in the interpretation of scRNA-seq data has gained widely acceptance. However, current methods face several challenges, including incomplete structure-preserving strategies and high distortion in embeddings, which fail to effectively model complex cell trajectories with multiple branches.
View Article and Find Full Text PDFBrief Bioinform
November 2024
Biotherapeutics Molecule Discovery, Boehringer Ingelheim Pharmaceutical Inc., 900 Ridgebury Road, Ridgefield, CT 06877, United States.
Antibody generation requires the use of one or more time-consuming methods, namely animal immunization, and in vitro display technologies. However, the recent availability of large amounts of antibody sequence and structural data in the public domain along with the advent of generative deep learning algorithms raises the possibility of computationally generating novel antibody sequences with desirable developability attributes. Here, we describe a deep learning model for computationally generating libraries of highly human antibody variable regions whose intrinsic physicochemical properties resemble those of the variable regions of the marketed antibody-based biotherapeutics (medicine-likeness).
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