摘要

To express an increased level of recombinant Mefp1(marine mussel adhesive protein) in soluble form, we constructed expression vectors encoding truncated OmpA signal peptide-Mefp1 fusion proteins. OmpA signal peptide (OmpASP) is the 21 residue peptide fragment of the 23 residue OmpA signal sequence cleavable by signal peptidase 1. We successfully produced increased levels of soluble recombinant Mefp1 (rMefp1) with various deletions of OmpASP, and found that the increased expression was caused by the increased pl of the N-terminus of the fusion proteins (<= 10.55). All the OmpA signal peptide segments of 3-21 amino acids in length had the same pl value (10.55). Our results suggest that the pl value of the truncated Omp-ASP (OmpASPO(tr)) play an important role in directional signaling for the fusion protein, but we found no evidence for the presence of a secretion enhancer in OmpASP. For practical applications, we increased the expression of soluble rMefp1 with OmpASP(tr) peptides as directional signals, and obtained rMefp1 with the native amino terminus (nN-rMefp1) using an OmpASP(tr)vertical bar Xa leader sequence that contains the recognition site for Xa protease.

  • 出版日期2008-7-31