کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1394076 | 984032 | 2008 | 10 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Tryptophan Aminopeptidase Activity of Several Indole Prenyltransferases from Aspergillus fumigatus Tryptophan Aminopeptidase Activity of Several Indole Prenyltransferases from Aspergillus fumigatus](/preview/png/1394076.png)
SummaryRecently, five indole prenyltransferases from Aspergillus fumigatus have been proven biochemically to be responsible for prenylations of diverse substrates. In this study, we show peptidase activities of 7-DMATS, FgaPT1, CdpNPT, and FtmPT1, with preference for linear peptides containing a tryptophanyl moiety at the N terminus. Testing of 31 peptides revealed that these enzymes shared similar substrate specificity and accepted H-L-Trp-L-Ala-OH and H-L-Trp-Gly-OH as best substrates for aminopeptidase activity. By using H-L-Trp-Gly-OH as substrate, Km values at 350, 380, 300, and 420 μM and enzymatic rate constants kcat/Km at 0.51, 0.24, 0.53, and 0.14 mM−1s−1 were determined for 7-DMATS, FgaPT1, CdpNPT, and FtmPT1, respectively. In contrast to prenyltransferase activities, the aminopeptidase activities were strongly or completely inhibited by EDTA. Mn2+ increased the aminopeptidase activities of FtmPT1 and CdpNPT up to 4- and 6-fold, respectively. To the best of our knowledge, this is the first report on the catalytic promiscuity of prenyltransferases.
Journal: - Volume 15, Issue 7, 21 July 2008, Pages 729–738