New Analogues of Proline-Rich Protein Fragments. Synthesis and Their Effect on Resistance of Murine Thymocytes to Hydrocortisone

New analogues of proline-rich protein (PRP) fragment were synthesized by the solid phase method using Boc/Bzl procedure. Dimer of the nonapeptide as well as dimer, trimer and tetramer of hexapeptide fragments of PRP possessing immunotropic activity were obtained. Effect of the peptides on the resistance of murine thymocytes to hydrocortisone was the same as that of the reference compounds (hexapeptide and nonapeptide). Key words: PRP fragments analogues, solid phase peptide synthesis, immunotropic activity A proline-rich protein (PRP) was isolated by Janusz et al. from ovine colostrum The aim of the present paper was to obtain synthetic analogues of NP and HP, which could replace PRP isolated from colostrum and might show the same or even Biochem., 138, 9 (1984)]

Mechanism of the activation of proteinase inhibitor synthesis by systemin involves beta-sheet structure, a specific DNA-binding protein domain

We analyzed a tertiary structure of systemin, the first identified polypeptide plant hormone, using two-dimensional NMR spectroscopy. From these data and molecular dynamics calculations we concluded that the peptide can adopt a Z-like-beta-sheet structure, which has previously been found in many specific DNA-binding proteins. Using DNA-cellulose affinity chromatography, we showed that systemin binds strongly to DNA. We suggest that the specific systemin-DNA interaction, particularly in a promoter region of the proteinase inhibitors, could effect gene expression and thus explain the biological activity of systemin