کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
10803609 | 1057162 | 2014 | 7 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Purification and enzymatic characterization of tobacco leaf β-N-acetylhexosaminidase
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کلمات کلیدی
PEPC(GlcNAc)3(GlcNAc)2NADP-MEN,N′-DiacetylchitobioseChitooligomersGlcNGalNAcGalNGDHN-acetyl-d-glucosamineGlcNAcRuBisCOPVPBSA - BSAd-Galactosamine - d-گالاکتوزامینd-glucosamine - D-گلوکوزامینN-Acetyl-D-Galactosamine - N-استیل D-گالاکتوزامینβ-N-acetylhexosaminidase - β-N-استیلهگزاسامینیدازbovine serum albumin - آلبومین سرم گاوNADP-malic enzyme - آنزیم NADP-malicCapillary electrophoresis - الکتروفورزمویرگیPhosphoenolpyruvate carboxylase - فسفوآنولپیروات کربوکسیلازglutamate dehydrogenase - گلوتامات دهیدروژناز
موضوعات مرتبط
علوم زیستی و بیوفناوری
بیوشیمی، ژنتیک و زیست شناسی مولکولی
زیست شیمی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
The kinetic properties of β-N-acetylhexosaminidase purified from tobacco (Nicotiana tabacum L.) leaves have been investigated. In addition to chromogenic pNP derivates, N,Nâ²-diacetylchitobiose and N,Nâ²,Nâ³-triacetylchitotriose were also used as substrates of β-N-acetylhexosaminidase. The highest reaction rate and the affinity for the substrate were observed for pNP-GlcNAc; however, an excess of this substrate inhibits the reaction. The reaction rate with pNP-GalNAc as the substrate was found to be about 85% of that obtained with pNP-GlcNAc. The hydrolysis of acetylated chitooligomers by β-N-acetylhexosaminidase followed by separation and quantification using capillary electrophoresis was slower compared to pNP-GlcNAc. The pH optimum of β-N-acetylhexosaminidase for individual substrates was found at 4.3-5.0 and the temperature optimum was 50-55 °C. Gel permeation chromatography and red native electrophoresis determined the relative molecular weight as 280 000 and the isoelectric point as 5.3. The inhibition of β-N-acetylhexosaminidase by monosaccharides GlcN, GalN, GlcNAc, GalNAc in combination with substrates pNP-GlcNAc and pNP-GalNAc was studied and the type of inhibition and the inhibition constants were determined.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biochimie - Volume 107, Part B, December 2014, Pages 263-269
Journal: Biochimie - Volume 107, Part B, December 2014, Pages 263-269
نویسندگان
Helena RyÅ¡lavá, Robert Valenta, Veronika Hýsková, TomáÅ¡ KÅÞek, JiÅà Liberda, Pavel Coufal,