The chitinase-like protein YKL-40 (CHI3L1) has been implicated in the pathophysiology of inflammation and cancer. Recent studies highlight the growing interest in targeting and blocking the activity of YKL-40 to treat cancer. Some of those targeting-strategies have been developed to directly block the heparin-affinity of YKL-40 with promising results.
View Article and Find Full Text PDFProtein stability is a widely studied topic, there are still aspects however that need addressing. In this paper we examined the effects of multiple proline substitutions into loop regions of the kinetically stable proteinase K-like serine protease VPR, using the thermostable structural homologue AQUI as a template. Four locations for proline substitutions were chosen to imitate the structure of AQUI.
View Article and Find Full Text PDFBiochim Biophys Acta Proteins Proteom
February 2019
Cloning into a pET 11a vector, followed by high-level expression of the cold adapted subtilase, VPR, utilizing the rhamnose titratable T7 system of Lemo21, resulted in a dramatic increase of soluble protein compared to the older system used. Expression optimization clearly shows the importance of calcium in the medium after induction, both for stability of the proteinase and cell health. Characterization of the purified enzyme obtained in a redesigned purification protocol which removed apparent RNA contaminants, resulted in a significantly higher value for k than previously reported.
View Article and Find Full Text PDFStructural comparisons of the cold adapted subtilase VPR and its thermophilic homologue, aqualysin I (AQUI) indicated the presence of additional salt bridges in the latter. Few of those appear to contribute significantly to thermal stability of AQUI. This includes a putative salt bridge between residues Lys142 and Glu172 as its deletion did not have any significant effect on its stability or activity (Jónsdóttir et al.
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