352-97-6Relevant articles and documents
Biosynthesis of a New Fusaoctaxin Virulence Factor in Fusarium graminearum Relies on a Distinct Path to Form a Guanidinoacetyl Starter Unit Priming Nonribosomal Octapeptidyl Assembly
Chen, Dandan,Liu, Wen,Tang, Haoyu,Tang, Weihua,Tang, Zhijun,Wang, Wanqiu,Xue, Yufeng
, p. 19719 - 19730 (2021/11/30)
Fusarium graminearum is a pathogenic fungus causing huge economic losses worldwide via crop infection leading to yield reduction and grain contamination. The process through which the fungal invasion occurs remains poorly understood. We recently characterized fusaoctaxin A in F. graminearum, where this octapeptide virulence factor results from an assembly line encoded in fg3_54, a gene cluster proved to be involved in fungal pathogenicity and host adaptation. Focusing on genes in this cluster that are related to fungal invasiveness but not to the biosynthesis of fusaoctaxin A, we here report the identification and characterization of fusaoctaxin B, a new octapeptide virulence factor with comparable activity in wheat infection. Fusaoctaxin B differs from fusaoctaxin A at the N-terminus by possessing a guanidinoacetic acid (GAA) unit, formation of which depends on the combined activities of the protein products of fgm1-3. Fgm1 is a cytochrome P450 protein that oxygenates l-Arg to 4(R)-hydroxyl-l-Arg in a regio- and stereoselective manner. Then, Cβ-Cγ bond cleavage proceeds in the presence of Fgm3, a pyridoxal-5′-phosphate-dependent lyase, giving guanidinoacetaldehyde and l-Ala. Rather than being directly oxidized to GAA, the guanidine-containing aldehyde undergoes spontaneous cyclization and subsequent enzymatic dehydrogenation to provide glycociamidine, which is linearized by Fgm2, a metallo-dependent amidohydrolase. The GAA path in F. graminearum is distinct from that previously known to involve l-Arg:l-Gly aminidotransferase activity. To provide this nonproteinogenic starter unit that primes nonribosomal octapeptidyl assembly, F. graminearum employs new chemistry to process l-Arg through inert C-H bond activation, selective C-C bond cleavage, cyclization-based alcohol dehydrogenation, and amidohydrolysis-associated linearization.
Clean production method of mercaptan compound
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Paragraph 0022, (2017/01/02)
The invention provides a clean production method of a mercaptan compound. There are two technological steps: Step 1, thiourea and halogenated hydrocarbon or active conjugated alkene react at 20-150 DEG C for 1-18 h, and after neutralization, S-alkylisothiourea is obtained; and Step 2, S-alkylisothiourea and aliphatic primary amine or secondary amine react at 20-180 DEG C for 1-24 h to obtain the mercaptan compound, and simultaneously, a substituted guanidino compound is coproduced. The mercaptan production technology has mild condition and high yield, hardly has discharge of ''three wastes (waste gas, waste water and industrial residue) '', and is a clean production method.
Meteorites as catalysts for prebiotic chemistry
Saladino, Raffaele,Botta, Giorgia,Delfino, Michela,Di Mauro, Ernesto
, p. 16916 - 16922 (2014/01/06)
From outer space: Twelve meteorite specimens, representative of their major classes, catalyse the synthesis of nucleobases, carboxylic acids, aminoacids and low-molecular-weight compounds from formamide (see figure). Different chemical pathways are identified, the yields are high for a prebiotic process and the products come in rich and composite panels.
