51-45-6Relevant academic research and scientific papers
Development of a novel L-histidine assay method using histamine dehydrogenase and a stable mutant of histidine decarboxylase
Yamaguchi, Hiroki,Nakata, Kunio,Tatsumi, Moemi,Sugiki, Masayuki,Miyano, Hiroshi,Mizukoshi, Toshimi
, p. 13 - 20 (2019)
L-Histidine analysis is essential in physiological research and clinical applications because L-histidine concentrations in biofluids are associated with various diseases. However, an enzymatic method for L-histidine quantitation has not yet been established. Here, we describe a novel L-histidine quantitation assay using a combination of histidine decarboxylase (HDC) and histamine dehydrogenase (HDH) enzymes. Wild-type HDC is unstable and completely lost its activity within 50 days of storage at 4 °C in solution. We rationally designed a HDC C57S mutant with markedly improved stability (storage at 4 °C for over 200 days) without altering the enzyme's substrate specificity. Together with HDH, the HDC C57S mutant was applied to quantify L-histidine concentrations in human plasma. The assay showed high precision (2.0% inter-assay variation) and high accuracy (5.8% deviation from the results of LC/MS).
Imidazole-modified porphyrin as a pH-responsive sensitizer for cancer photodynamic therapy
Zhu, Xianchun,Lu, Wentong,Zhang, Yazhou,Reed, Aisha,Newton, Brandon,Fan, Zhen,Yu, Hongtao,Ray, Paresh C.,Gao, Ruomei
, p. 10311 - 10313 (2011)
5,10,15,20-Tetrakis(N-(2-(1H-imidazol-4-yl)ethyl)benzamide)porphyrin produced twice as many singlet oxygen (1O2) molecules at pH 5.0 (quantum yield 0.53 ± 0.01) than at pH 7.4, whereas the 1O2 quenching rate was reduced by a factor of 2.5 for a pH change from 7.4 to 5.0.
The intrinsic basicity of 4(5)-2′-aminoethylimidazole (histamine)
Hernández-Laguna,Abboud,Notario,Homan,Smeyers
, p. 1450 - 1454 (1993)
The gas-phase basicity (GB) of histamine (1) relative to ammonia (defined as the standard Gibbs energy change for reaction 1) has been measured by means of Fourier transform ion cyclotron resonance spectroscopy (FT-ICR): 1H+(g) + NH3(g) ? 1(g) + NH4+(g). The various tautomer/conformers of 1H+(g) were studied by means of ab initio SCF-LCAO-MO calculations at the 6-31G//6-31G level. The calculated proton affinity agrees well with that estimated from FT-ICR results. Ring protonation is slightly preferred over side-chain protonation. Chelation provides a major contribution to the stability of 1H+(g). Comparison of these results with aqueous solution data reveals dramatic differences due to solvation.
Partial Purification and Characterization of A Novel Histidine Decarboxylase from Enterobacter aerogenes DL-1
Zou, Yu,Hu, Wenzhong,Jiang, Aili,Tian, Mixia
, p. 605 - 615 (2015)
Histidine decarboxylase (HDC) from Enterobacter aerogenes DL-1 was purified in a three-step procedure involving ammonium sulfate precipitation, Sephadex G-100, and DEAE-Sepharose column chromatography. The partially purified enzyme showed a single protein band of 52.4 kD on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The optimum pH for HDC activity was 6.5, and the enzyme was stable between pH 4 and 8. Enterobacter aerogenes HDC had optimal activity at 40°C and retained most of its activity between 4 and 50°C. HDC activity was reduced in the presence of numerous tested compounds. Particularly with SDS, it significantly (p 2+ and Mn2+ showed prominent activation effects (p m and Vmax values of the enzyme for L-histidine were 0.21 mM and 71.39 μmol/min, respectively. In comparison with most HDCs from other microorganisms and animals, HDC from E. aerogenes DL-1 displayed higher affinity and greater reaction velocity toward L-histidine.
A single amino acid substitution converts a histidine decarboxylase to an imidazole acetaldehyde synthase
Takeshima, Daiki,Mori, Ayaka,Ito, Hideyuki,Komori, Hirofumi,Ueno, Hiroshi,Nitta, Yoko
, (2020)
Histidine decarboxylase (HDC; EC 4.1.1.22), an enzyme that catalyzes histamine synthesis with high substrate specificity, is a member of the group II pyridoxal 5′-phosphate (PLP) -dependent decarboxylase family. Tyrosine is a conserved residue among group II PLP-dependent decarboxylases. Human HDC has a Y334 located on a catalytically important loop at the active site. In this study, we demonstrated that a HDC Y334F mutant is capable of catalyzing the decarboxylation-dependent oxidative deamination of histidine to yield imidazole acetaldehyde. Replacement of the active-site Tyr with Phe in group II PLP-dependent decarboxylases, including mammalian aromatic amino acid decarboxylase, plant tyrosine/DOPA decarboxylase, and plant tryptophan decarboxylase, is expected to result in the same functional change, given that a Y-to-F substitution at the corresponding residue (number 260) in the HDC of Morganella morganii, another group II PLP-dependent decarboxylase, yielded the same effect. Thus, it was suggested that the loss of the OH moiety from the active-site Tyr residue of decarboxylase uniquely converts the enzyme to an aldehyde synthase.
Interaction pattern of histidine, carnosine and histamine with methylglyoxal and other carbonyl compounds
Ghassem Zadeh, Raheleh,Yaylayan, Varoujan
, (2021)
The ability of histidine to scavenge sugar-derived 1,2-dicarbonyl compounds was investigated using aqueous methanolic model systems containing histidine or histamine in the presence of glucose, methylglyoxal, or glyoxal. The samples were prepared either a
Organocatalytic Decarboxylation of Amino Acids as a Route to Bio-based Amines and Amides
Claes, Laurens,Janssen, Michiel,De Vos, Dirk E.
, p. 4297 - 4306 (2019/08/26)
Amino acids obtained by fermentation or recovered from protein waste hydrolysates represent an excellent renewable resource for the production of bio-based chemicals. In an attempt to recycle both carbon and nitrogen, we report here on a chemocatalytic, metal-free approach for decarboxylation of amino acids, thereby providing a direct access to primary amines. In the presence of a carbonyl compound the amino acid is temporarily trapped into a Schiff base, from which the elimination of CO2 may proceed more easily. After evaluating different types of aldehydes and ketones on their activity at low catalyst loadings (≤5 mol%), isophorone was identified as powerful organocatalyst under mild conditions. After optimisation many amino acids with a neutral side chain were converted in 28–99 % yield in 2-propanol at 150 °C. When the reaction is performed in DMF, the amine is susceptible to N-formylation. This consecutive reaction is catalysed by the acidity of the amino acid reactant itself. In this way, many amino acids were efficiently transformed to the corresponding formamides in a one-pot catalytic system.
Synthetic method of histamine dichloride
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Paragraph 0008; 0013, (2017/03/24)
The invention discloses a synthetic method of histamine dichloride, and belongs to the field of drug synthesis. The synthetic method comprises the following steps: preparing a cyano methylimidazole intermediate through oxidization of TCCA (Trichloroisocyanuric Acid) under an alkaline condition by taking L-histidine as an original raw material, and then preparing medicinal histamine dichloride through catalytic hydrogenation and one-step salifying process. In the histamine dichloride compounded through the synthetic method, the content of related substances is less than 0.5 percent, the content of a single impurity is less than 0.1 percent, and the histamine dichloride accords with medicinal level. A reagent adopted by the technology is cheap and of low-toxicity, the reaction is safe and reliable, an alcohol solvent can be recycled, after-treatment operation is simple and convenient, and the technology is environment-friendly and is beneficial for large-scale industrial production.
A histamine dihydrochloride synthetic method
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Paragraph 0027; 0028; 0029, (2017/08/25)
The invention discloses a histamine dihydrochloride synthesis method. Through addition of a catalyst (copper bromide), the decarboxylation temperature is reduced, the types and the contents of unknown impurities are reduced, the raw material conversion rate is increased, the end product purity is improved, and energy consumption reduction and easy industrialisation are realized. Through the step of injecting hydrogen chloride gas to prepare hydrochlorate, the step of preparing a hydrogen chloride solution is omitted and the operation is simplified.
HIV INTEGRASE INHIBITORS
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, (2015/09/22)
The present invention features compounds that are HIV integrase inhibitors and therefore are useful in the inhibition of HIV replication, the prevention and/or treatment of infection by HIV, and in the treatment of AIDS and/or ARC.
