کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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2021700 | 1069257 | 2006 | 11 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Cloning, sequencing, expression, and characterization of protealysin, a novel neutral proteinase from Serratia proteamaculans representing a new group of thermolysin-like proteases with short N-terminal region of precursor Cloning, sequencing, expression, and characterization of protealysin, a novel neutral proteinase from Serratia proteamaculans representing a new group of thermolysin-like proteases with short N-terminal region of precursor](/preview/png/2021700.png)
The gene of Serratia proteamaculans proteinase, protealysin, was cloned, sequenced, and expressed in Escherichia coli. The gene encoded a precursor of 341 amino acids (AAs) with a significant homology to thermolysin-like proteinases (TLPs). The molecular weight of the purified mature active recombinant protein was 32 kDa, the N-terminal amino acid sequence was AKTSTGGEVI. The optimum pH for azocasein hydrolysis by protealysin was seven and it was completely inhibited by o-phenanthroline. The enzyme hydrolyzed 3-(2-furyl)acryloyl-glycyl-l-leucine amide, the standard substrate for TLPs, with kcat/Km ratio of (2.52 ± 0.02) × 102 M−1 s−1. Protealysin maturation removes 50 AA from the N-terminus of the precursor. The removed region had no similarity with the preprosequence of thermolysin (232 AA) but was homologous to some other TLPs. These proteins shared a conserved 7-AA motif near the initial methionine. Such motif was also found in some nonproteolytic putative proteins; two of them were eukaryotic.
Journal: Protein Expression and Purification - Volume 47, Issue 2, June 2006, Pages 551–561