Deactivation pathways of electronically excited states have been investigated in three protonated aromatic amino acids: tryptophan (Trp), tyrosine (Tyr) and phenylalanine (Phe). The protonated amino acids were generated by electrospray and excited with a 266 nm femtosecond laser, the subsequent decay of the excited states being monitored through fragmentation of the ions induced and/or enhanced by another femtosecond pulse at 800 nm. The excited state of TrpH+ decays in 380 fs and gives rise to two channels: hydrogen atom dissociation or internal conversion (IC). In TyrH, the decay is slowed down to 22.3 ps and the fragmentation efficiency of PheH+ is so low that the decay cannot be measured with the available laser. The variation of the excited state lifetime between TrpH+ and TyrH+ can be ascribed to energy differences between the dissociative pi sigma* state and the initially excited pi pi* state.
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ACS Nano
January 2025
State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China.
Under a changing climate, enhancing the drought resilience of crops is critical to maintaining agricultural production and reducing food insecurity. Here, we demonstrate that seed priming with amorphous silica (SiO) nanoparticles (NPs) (20 mg/L) accelerated seed germination speed, increased seedlings vigor, and promoted seedling growth of rice under polyethylene glycol (PEG)-mimicking drought conditions. An orthogonal approach was used to uncover the mechanisms of accelerated seed germination and enhanced drought tolerance, including electron paramagnetic resonance, Fourier transform infrared spectroscopy (FTIR), metabolomics, and transcriptomics.
View Article and Find Full Text PDFACS Chem Biol
January 2025
Division of Physiological Chemistry and Metabolism, Faculty of Pharmacy, Keio University, 1-5-30 Shibakoen, Minato-ku, Tokyo 105-0011, Japan.
Macrophages remove apoptotic cells via phagocytosis, also known as efferocytosis, during inflammation to maintain tissue homeostasis. This process is accompanied by various metabolic changes in macrophages including the production of lipid metabolites by fatty acid oxygenases. Among these, highly reactive metabolites, called lipid-derived electrophiles (LDEs), modify cysteines and other nucleophilic amino acids in intracellular proteins.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Department of Pain Management, Qilu Hospital of Shandong University, 107# West Wenhua Road, Jinan, Shandong 250012, China. Electronic address:
This investigation represents a pioneering effort to examine the therapeutic effects of PCB specifically in the context of CFA-induced mice, as well as to elucidate the underlying mechanisms that facilitate such effects. Our study utilized advanced methodologies, namely high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS)-based metabolomics, alongside comprehensive multivariate data analysis, to identify a distinctive metabolic profile associated with acute inflammation. Through our analyses, we discovered that several potential metabolites were significantly implicated in a variety of critical metabolic pathways.
View Article and Find Full Text PDFComp Biochem Physiol C Toxicol Pharmacol
January 2025
Key Laboratory of South China Sea Fishery Resources Exploitation & Utilization, Ministry of Agriculture and Rural Affairs, South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, Guangdong 510300, China. Electronic address:
The small abalone (Haliotis diversicolor) is an economic shellfish cultured in the south coast of China. In recent years, the frequent occurrence of the disease has led to significant mortality in abalone farms. Deleted in malignant brain tumors 1 (DMBT1), a member of the scavenger receptor cysteine-rich (SRCR) protein family, plays an important role in host defense.
View Article and Find Full Text PDFActa Physiol (Oxf)
February 2025
Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
Purpose: Homoarginine (hArg) is an arginine metabolite that has been known for years, but its physiological role in the body remains poorly understood. For instance, it is well known that high hArg concentrations in the blood are protective against several disease states, yet the mechanisms behind these health benefits are unclear. This review compiles what is known about hArg, namely its synthetic pathways, its role in different diseases and conditions, and its proposed mechanisms of action in humans and experimental animals.
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