The immunosuppressant drug rapamycin, also known as Sirolimus, underwent autoxidation under mild conditions to give numerous monomeric and oligomeric compounds, which were generally characterized by size-exclusion chromatography and NP-HPLC with UV and MS detection. Some of the more predominant products, epoxides and ketones, were isolated and identified. Two epoxides and 10S-epimer of rapamycin were described for the first time. Observed rapamycin isomers were also addressed. Computational chemistry was used to provide mechanistic insights. Formation of the majority of the rapamycin products could be rationalized with free radical-mediated autoxidation reactions involving alkene and alcohol sites. Methodological aspects of oxidative stress testing are discussed.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.jpba.2011.10.017 | DOI Listing |
Nat Struct Mol Biol
January 2025
Key Laboratory of RNA Innovation, Science, and Engineering; Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai, China.
Lysosomal membrane protein LYCHOS (lysosomal cholesterol signaling) translates cholesterol abundance to mammalian target of rapamycin activation. Here we report the 2.11-Å structure of human LYCHOS, revealing a unique fusion architecture comprising a G-protein-coupled receptor (GPCR)-like domain and a transporter domain that mediates homodimer assembly.
View Article and Find Full Text PDFNat Struct Mol Biol
January 2025
Division of Nephrology and Kidney Research Institute, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China.
Cholesterol plays a pivotal role in modulating the activity of mechanistic target of rapamycin complex 1 (mTOR1), thereby regulating cell growth and metabolic homeostasis. LYCHOS, a lysosome-localized G-protein-coupled receptor-like protein, emerges as a cholesterol sensor and is capable of transducing the cholesterol signal to affect the mTORC1 function. However, the precise mechanism by which LYCHOS recognizes cholesterol remains unknown.
View Article and Find Full Text PDFBiochem Pharmacol
January 2025
Department of Cell Biology, Faculty of Medicine, Complutense University of Madrid, Spain; Institute of Medical Research at the San Carlos Clinic Hospital (IdISSC), Madrid, Spain.
PAS domain-containing serine/threonine-protein kinase (PASK) is a nutrient and energy sensor regulated by fasting/refeeding conditions in hypothalamic areas involved in controlling energy balance. In this sense, PASK plays a role in coordinating the activation/inactivation of AMP-activated protein kinase (AMPK) and mechanistic target of rapamycin (mTOR) in response to fasting. PASK deficiency protects against the development of diet-induced obesity.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Integrative Science Center of Germplasm Creation in Western China (CHONGQING) Science City, Biological Science Research Center, Southwest University, Chongqing 400715, China. Electronic address:
Storage proteins (SPs) are hexameric macromolecular protein, an important component of insect serum protein, which plays a variety of roles in insect metamorphosis and development. However, their regulatory mechanisms remain unclear. Our previous studies revealed that the expression of SPs is regulated by nutritional signals and identified FoxO as a negative regulator of SPs in the silkworm Bombyx mori (B.
View Article and Find Full Text PDFDev Cell
January 2025
Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada; Ted Rogers Centre for Heart Research, University of Toronto, Toronto, ON M5G 1M1, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada; Developmental and Stem Cell Biology Program, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada. Electronic address:
Embryonic wounds repair rapidly, with no inflammation or scarring. Embryonic wound healing is driven by collective cell movements facilitated by the increase in the volume of the cells adjacent to the wound. The mechanistic target of rapamycin (mTor) complex 1 (TORC1) is associated with cell growth.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!