کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1987606 1540320 2007 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Inhibitory kinetics of bromacetic acid on β-N-acetyl-d-glucosaminidase from prawn (Penaeus vannamei)
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
Inhibitory kinetics of bromacetic acid on β-N-acetyl-d-glucosaminidase from prawn (Penaeus vannamei)
چکیده انگلیسی

β-N-Acetyl-d-glucosaminidase (NAGase, EC.3.2.1.52), a composition of chitinases, cooperates with endo-chitinase and exo-chitinase to disintegrate chitin into N-acetylglucosamine (NAG). NAGase from prawn (Penaeus vannamei) is involved in digestion and molting processes. The investigation of enzymatic properties, functional groups and catalytic mechanism is an essential mission to its commercial application. Bromacetic acid (BrAc) is a specific modifier for the histidine residue in specific condition. In this paper, the effect of BrAc on prawn NAGase activity for the hydrolysis of pNP-NAG has been investigated. The results showed that BrAc can reversibly and non-competitively inhibit the enzyme activity at appropriate concentrations and the value of IC50 was estimated to be 17.05 ± 0.65 mM. The inhibition kinetics of the enzyme by BrAc has been studied using the kinetic method of the substrate reaction. And the inhibition model was set up and the microscopic rate constants for the reaction of the inhibitor with free enzyme and the enzyme–substrate complexes were determined for inactivation and reactivation. The rate constant of the forward inactivation (k+0), which is 1.25 × 10−3 s−1, is about eight times as much as that of the reverse reactivation (k−0), which is 1.64 × 10−4 s−1. Therefore, when the BrAc concentration is sufficiently large, the enzyme is completely inactivated.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Biological Macromolecules - Volume 41, Issue 3, 1 August 2007, Pages 308–313
نویسندگان
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