The incorporation into the thiazole moiety of thiamine of several labeled compounds has been studied on short time incubations of washed-cells suspensions. No incorporation of radioactivity from [G-14C] methionine was found in a mutant auxotrophic for methionine. No radioactivity was incorporated from [U-14C] aspartate or from [U-14C] serine. The incorporation of 35S from sulphate was lowered by cysteine or glutathione but was unaffected by methionine or homocystine. Although the synthesis of thiazole is dependent on methionine, neither the sulphur atom nor the carbon chain of thiazole originate from methonine in E. coli. No carbon originates from cysteine which is the likely direct donor of sulphur.
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http://dx.doi.org/10.1016/s0300-9084(77)80219-8 | DOI Listing |
Proc Natl Acad Sci U S A
January 2025
Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114.
Ependymoma (EPN) is a common form of brain tumor in children, often resistant to available cytotoxic therapies. Molecular profiling studies have led to a better understanding of EPN subtypes and revealed a critical role of oncogenes ZFTA-RELA fusion and EPHB2 in supratentorial ependymoma (ST-EPN). However, the immune system's role in tumor progression and response to therapy remains poorly understood.
View Article and Find Full Text PDFNat Commun
January 2025
Department of Chemistry and Biochemistry, University of California, San Diego, CA, USA.
Cryo-EM structure determination of protein-free RNAs has remained difficult with most attempts yielding low to moderate resolution and lacking nucleotide-level detail. These difficulties are compounded for small RNAs as cryo-EM is inherently more difficult for lower molecular weight macromolecules. Here we present a strategy for fusing small RNAs to a group II intron that yields high resolution structures of the appended RNA.
View Article and Find Full Text PDFArch Pharm (Weinheim)
January 2025
Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Anadolu University, Eskişehir, Turkey.
Quinolone antibiotics are known for their antibacterial activity by inhibiting the enzyme DNA gyrase. Inspired by their mechanism, new compounds combining 1,4-dihydropyrimidine, a quinolone isostere, with pyridine/pyrimidine rings were synthesized. These derivatives showed antibacterial effects, likely through DNA gyrase inhibition, as supported by molecular docking and dynamics simulations.
View Article and Find Full Text PDFBMC Gastroenterol
January 2025
Department of Anesthesiology, First Affiliated Hospital, Fujian Medical University, No. 20, Cha Zhong Road, Fuzhou, Fujian Province, People's Republic of China.
Background: Visceral pain sensitization and emotional reactions due to irritable bowel syndrome (IBS) occur frequently in the general population. Oxidative stress plays a crucial role in the pathogenesis of IBS. Previous studies have demonstrated that activation of peroxisome proliferator-activated receptor gamma (PPARγ) has analgesic effects.
View Article and Find Full Text PDFJ Biochem Mol Toxicol
February 2025
Department of Chemistry, Science Faculty, Karabuk University, Karabuk, Turkey.
In this study, four novels 2,5,6-trisubstituted imidazothiadiazole derivative ligands and their Ag(I) complexes were synthesized and characterized using various spectroscopic analysis techniques. First, imidazo[2,1-b][1,3,4]thiadiazole derivative (3) was obtained from the reaction of 5-amino-1,3,4-thiadiazole-2-thiol with benzyl bromide in the presence of KOH in an ethanolic medium. In the next step, the resultant compound reacted sequentially with four substituted phenacyl bromide derivatives (4a-4d) under refluxed ethanol for 24 h to obtain substituted 2-(benzylthio)-6-phenylimidazo[2,1-b][1,3,4]thiadiazole derivatives (5-8).
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