137-00-8Relevant articles and documents
Structure of a Clostridium botulinum C143S thiaminase I/thiamin complex reveals active site architecture
Sikowitz, Megan D.,Shome, Brateen,Zhang, Yang,Begley, Tadhg P.,Ealick, Steven E.
, p. 7830 - 7839 (2013)
Thiaminases are responsible for the degradation of thiamin and its metabolites. Two classes of thiaminases have been identified based on their three-dimensional structures and their requirements for a nucleophilic second substrate. Although the reactions of several thiaminases have been characterized, the physiological role of thiamin degradation is not fully understood. We have determined the three-dimensional X-ray structure of an inactive C143S mutant of Clostridium botulinum (Cb) thiaminase I with bound thiamin at 2.2 A resolution. The C143S/thiamin complex provides atomic level details of the orientation of thiamin upon binding to Cb-thiaminase I and the identity of active site residues involved in substrate binding and catalysis. The specific roles of active site residues were probed by using site directed mutagenesis and kinetic analyses, leading to a detailed mechanism for Cb-thiaminase I. The structure of Cb-thiaminase I is also compared to the functionally similar but structurally distinct thiaminase II.
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Buchman
, p. 1803 (1936)
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Oxygen Vacancy-Engineered PEGylated MoO3 ?x Nanoparticles with Superior Sulfite Oxidase Mimetic Activity for Vitamin B1 Detection
Chen, Yuan,Chen, Tongming,Wu, Xiaoju,Yang, Guowei
, (2019)
Sulfite oxidase (SuOx) is a molybdenum-dependent enzyme that catalyzes the oxidation of sulfite to sulfate to maintain the intracellular levels of sulfite at an appropriate low level. The deficiency of SuOx would cause severe neurological damage and infant diseases, which makes SuOx of tremendous biomedical importance. Herein, a SuOx mimic nanozyme of PEGylated (polyethylene glycol)-MoO3 ?x nanoparticles (P-MoO3 ?x NPs) with abundant oxygen vacancies created by vacancy-engineering is reported. Their level of SuOx-like activity is 12 times higher than that of bulk-MoO3. It is also established that the superior increased enzyme mimetic activity is due to the introduction of the oxygen vacancies acting as catalytic hotspots, which allows better sulfite capture ability. It is found that vitamin B1 (VB1) inhibits the SuOx mimic activity of P-MoO3 ?x NPs through the irreversible cleavage by sulfite and the electrostatic interaction with P-MoO3 ?x NPs. A colorimetric platform is developed for the detection of VB1 with high sensitivity (the low detection limit is 0.46 μg mL?1) and good selectivity. These findings pave the way for further investigating the nanozyme which possess intrinsic SuOx mimicing activity and is thus a promising candidate for biomedical detection.
Karrer et al.
, p. 1523,1525 (1945)
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Hatcher
, p. 465 (1947)
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Characterization of 2-methyl-4-amino-5-(2-methyl-3-furylthiomethyl)pyrimidine from thermal degradation of thiamin
Jhoo, Jin-Woo,Lin, Ming-Chi,Sang, Shengmin,Cheng, Xiaofang,Zhu, Nanqun,Stark, Ruth E.,Ho, Chi-Tang
, p. 4055 - 4058 (2002)
Thiamin hydrochloride was thermally degraded in phosphate buffer (pH 6.5) at 110 °C for 2 h. A major decomposition product was isolated by column chromatography and structurally identified by spectrometric techniques (1H NMR, 13C NMR
Kinetics and mechanistic study of manganese(II)-catalyzed cerium(IV) oxidation of thiamine hydrochloride in aqueous perchloric acid medium by stopped flow technique
Naik,Byadagi,Nandibewoor,Chimatadar
, p. 1307 - 1317 (2013)
The kinetics of the manganese(II)-catalyzed oxidation of thiamine hydrochloride by cerium(IV) in aqueous perchloric acid medium at a constant ionic strength of 1.10 mol dm-3 was studied spectrophotometrically at 15, 25, 35, and 45 C by the stopped flow technique. The reaction between thiamine hydrochloride and cerium(IV) in the acid medium exhibits 1:3 stoichiometry. The main products were identified by spot test, IR, 1H NMR, and GC-MS studies. The reaction is first order in cerium(IV) and manganese(II) and has less than unit order in thiamine hydrochloride. As the acid concentration increases the rate of reaction decreases. The added product cerium(III) retards the rate of reaction. The active catalyst and oxidant species were identified as [Mn(H2O)4]2+ and [Ce(OH)]3+, respectively. A probable mechanism involving free radicals and the formation of a complex between substrate and catalyst is proposed. The reaction constants, activation parameters, and thermodynamic quantities are calculated and discussed.
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Rubtsov,Shapira
, (1970)
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Synthetic method of thiazoles (by machine translation)
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Paragraph 0016; 0020-0021; 0025-0026; 0030, (2020/09/16)
4 - Acetoxy 3 - acetyl -3 - chloropropyl acetate is hydrolyzed under acidic conditions to prepare 4 -mercapto -2 - methyl -2 - (β - acetoxyethyl)-thiazole; the step of preparing -2 - methyl -2 - (β - acetoxyethyl)-thiazole with 3 - methyl -3 - (β - acetoxyethyl)-thiazole under acidic condition is carried out under an acidic condition by adding an oxidizing agent under an acidic condition in 3 -chloro -3 -methyl 2 - (β - acetoxyethyl)-thiazole in an acidic condition under an acidic condition by adding 4 - an oxidizing agent under an acidic condition; and a -5 - method -5 - for synthesizing thiazoles -4 - and -5 -mercapto 2 -methyl-ethyl)-thiazole in an acidic condition by adding an -5 - oxidizing agent under an -5 - 4 - acidic condition; and the method comprises the following steps: preparing -4 -4 - ethyl acetoxyethyl)-thiazole. The synthesis method is mild in overall reaction condition, simple in post-treatment and suitable for pilot scale test and industrial production. (by machine translation)
Biosynthesis of a thiamin antivitamin in clostridium botulinum
Cooper, Lisa E.,O'Leary, Seán E.,Begley, Tadhg P.
, p. 2215 - 2217 (2014/05/06)
Bacimethrin-derived 2′-methoxythiamin pyrophosphate inhibits microbial growth by disrupting metabolic pathways dependent on thiamin-utilizing enzymes. This study describes the discovery of the bacimethrin biosynthetic gene cluster of Clostridium botulinum A ATCC 19397 and in vitro reconstitution of bacimethrin biosynthesis from cytidine 5′-monophosphate.
