کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
10804375 | 1057260 | 2005 | 9 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
A chymotrypsin-like proteinase from the midgut of Tenebrio molitor larvae
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
STISUCTPCKTLCKE-64GLPpyroglutamylTenebrio molitorKunitz soybean trypsin inhibitorPMSFtosyl-l-phenylalanine chloromethyl ketonePNADMFp-Nitroanilide - p-nitroanilideAcetyl - استیلbenzoyl - بنزویلdimethyl formamide - دی متیل فرمامیدSuccinyl - ساکنینیلphenylmethylsulfonyl fluoride - فنیل متیل سولفونیل فلورایدposterior midgut - مرطوب خلفیanterior midgut - مرهم قدامیMidgut - میدگوستYellow mealworm - کرم خوراکی زردchymotrypsin - کیموتریپسین
موضوعات مرتبط
علوم زیستی و بیوفناوری
بیوشیمی، ژنتیک و زیست شناسی مولکولی
زیست شیمی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
A chymotrypsin-like proteinase was isolated from the posterior midgut of larvae of the yellow mealworm, Tenebrio molitor, by ion-exchange and gel filtration chromatography. The enzyme, TmC1, was purified to homogeneity as determined by SDS-PAGE and postelectrophoretic activity detection. TmC1 had a molecular mass of 23.0 kDa, pI of 8.4, a pH optimum of 9.5, and the optimal temperature for activity was 51 °C. The proteinase displayed high stability at temperatures below 43 °C and in the pH range 6.5-11.2, which is inclusive of the pH of the posterior and middle midgut. The enzyme hydrolyzed long chymotrypsin peptide substrates SucAAPFpNA, SucAAPLpNA and GlpAALpNA and did not hydrolyze short chymotrypsin substrates. Kinetic parameters of the enzymatic reaction demonstrated that the best substrate was SucAAPFpNA, with kcat app 36.5 s-1 and Km 1.59 mM. However, the enzyme had a lower Km for SucAAPLpNA, 0.5 mM. Phenylmethylsulfonyl fluoride (PMSF) was an effective inhibitor of TmC1, and the proteinase was not inhibited by either tosyl-l-phenylalanine chloromethyl ketone (TPCK) or Nα-tosyl-l-lysine chloromethyl ketone (TLCK). However, the activity of TmC1 was reduced with sulfhydryl reagents. Several plant and insect proteinaceous proteinase inhibitors were active against the purified enzyme, the most effective being Kunitz soybean trypsin inhibitor (STI). The N-terminal sequence of the enzyme was IISGSAASKGQFPWQ, which was up to 67% similar to other insect chymotrypsin-like proteinases and 47% similar to mammalian chymotrypsin A. The amino acid composition of TmC1 differed significantly from previously isolated T. molitor enzymes.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biochimie - Volume 87, Issue 8, August 2005, Pages 771-779
Journal: Biochimie - Volume 87, Issue 8, August 2005, Pages 771-779
نویسندگان
E.N. Elpidina, T.A. Tsybina, Y.E. Dunaevsky, M.A. Belozersky, D.P. Zhuzhikov, B. Oppert,