کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1975527 | 1060633 | 2012 | 8 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Purification, characterization and cDNA cloning of a trypsin from the hepatopancreas of snakehead (Channa argus)
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کلمات کلیدی
موضوعات مرتبط
علوم زیستی و بیوفناوری
بیوشیمی، ژنتیک و زیست شناسی مولکولی
زیست شیمی
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چکیده انگلیسی
A trypsin was purified from the hepatopancreas of snakehead (Channa argus) by ammonium sulfate fractionation and a series of column chromatographies including DEAE-Sepharose, Sephacryl S-200 HR and Hi-Trap Capto-Q. The molecular mass of the purified trypsin was about 22 kDa, as estimated by SDS-PAGE. The optimum pH and temperature of the purified trypsin were 9.0 and 40 °C, respectively. The trypsin was stable in the pH range of 7.5-9.5 and below 45 °C. The enzymatic activity was strongly inhibited by serine proteinase inhibitors, such as MBTI, Pefabloc SC, PMSF, LBTI and benzamidine. Peptide mass fingerprinting (PMF) of the purified protein obtained 2 peptide fragments with 25 amino acid residues and were 100% identical to the trypsinogen from pufferfish (Takifugu rubripes). The activation energy (Ea) of this enzyme was 24.65 kJ·Mâ 1. Apparent Km was 1.02 μM and kcat was 148 Sâ 1 for fluorogenic substrate Boc-Phe-Ser-Arg-MCA. A trypsinogen gene encoding 247 amino acid residues was further cloned on the basis of the sequence obtained from PMF and the conserved site peptide of trypsinogen together with 5â²-RACE and 3â²-RACE. The deduced amino acid sequence contains a signal peptide of 15 residues and an activation peptide of 9 amino acid residues with a mature protein of 223 residues. The catalytic triad His-64, Asp-107, Ser-201 and 12 Cys residues which may form 6 disulfide bonds were conserved. Compared with the PMF data, only 2 amino acid residues difference were identified, suggesting the cloned trypsinogen is quite possibly the precursor of the purified trypsin.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology - Volume 161, Issue 3, March 2012, Pages 247-254
Journal: Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology - Volume 161, Issue 3, March 2012, Pages 247-254
نویسندگان
Long-Zhen Zhou, Mi-Mi Ruan, Qiu-Feng Cai, Guang-Ming Liu, Le-Chang Sun, Wen-Jin Su, Min-Jie Cao,