A new cyclic pentapeptide, chrysosporide (1), was isolated from a New Zealand sample of the mycoparasitic fungus Sepedonium chrysospermum by bioactivity-guided fractionation. The planar structure was deduced by detailed spectroscopic analysis, and the absolute configurations of the amino acid residues were defined by Marfey's method. As both enantiomers of Leu occurred in chrysosporide, molecular mechanics calculations were applied to the analysis to distinguish between the possible structural isomers. Only the lowest energy conformers of the cyclo-(L-Val-D-Ala-L-Leu-L-Leu-D-Leu) isomer were in agreement with the observed NOEs, suggesting that this was the most probable amino acid sequence for chrysosporide (1).
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December 2024
Pingshan Translational Medicine Center, Shenzhen Bay Laboratory, Shenzhen, 518118, China.
Peptide self-assembly is a complex hierarchical process involving the progressive formation of secondary structures, such as α-helices, β-sheets, and turns, during the early stages. It is precisely these multi-component building blocks that contribute to the complexity of protein assemblies in living organisms. While coiled coils are well-understood in protein folding, determining the structural characteristics governing their lateral packing remains challenging.
View Article and Find Full Text PDFJ Nat Prod
December 2024
State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, P.R. China.
Nat Prod Res
November 2024
Center of Excellence for Innovation in Chemistry (PERCH-CIC), Department of Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand.
J Nanobiotechnology
September 2024
Key Laboratory of Emergency and Trauma of Ministry of Education, Engineering Research Center for Hainan Biological Sample Resources of Major Diseases, The Hainan Branch of National Clinical Research Center for Cancer, the First Clinical College & the First Affiliated Hospital, Hainan Medical University, Haikou, 570102, China.
Immunotherapy has shown marked progress in promoting systemic anti-colorectal cancer (CRC) clinical effects. For further effectively sensitizing CRC to immunotherapy, we have engineered a pH-sensitive zeolitic imidazolate framework-8 (CS/NPs), capable of efficient cGAS-STING pathway activation and immune checkpoint blockade, by encapsulating the chemotherapeutic mitoxantrone (MTX) and immunomodulator thymus pentapeptide (TP5) and tailoring with tumor-targeting chondroitin sulfate (CS). In this nanoframework, CS endows CS/NPs with specific tumor-targeting activity and reduced systemic toxicity.
View Article and Find Full Text PDFPharmaceutics
August 2024
Division of Technology Convergence, National Cancer Center, 323 Ilsan-ro, Goyang 10408, Republic of Korea.
The efficacy of glioblastoma treatment is closely associated with complete tumor resection. However, conventional surgical techniques often result in incomplete removal, leading to poor prognosis. A major challenge is the accurate delineation of tumor margins from healthy tissues.
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