Collagen is the most abundant structural protein in all animals. It is not only an important structural protein widely existing in connective tissue, but also plays a key role in cell division, tissue regeneration and other processes.

The specific triple-helical structure of collagen is always the hot topic in the protein research. And synthetic triple-helical peptides (THPs) that mimic the structure of native collagens have been used to investigate collagen protein interactions as well as collagen structure and stability. Numerous scaffolds have been used to create stable THPs which can be divided two categories (a) a scaffold to which the peptides are covalently attached (b) the use of metal ions for non-covalent association.

In Stawikowski et al work, they presented a convenient strategy for the synthesis of C-terminally branched, homotrimeric THPs compatible with Fmoc solid-phase chemistry. They constructed peptoid-containing THPs using solid-phase methodology while incorporating tricine as a branching scaffold and 1, 2-diaminoethane (DAE) or 1, 4-diaminobutane (DAB) as a linker. In their work, the peptide sequence was incorporated directly onto the linker and scaffold during solid-phase synthesis without additional manipulations.

The prepared THPs were compared to the unbranched sequence. And triple-helical conformations of these THPs were evaluated by circular dichroism spectroscopy. At room temperature, all peptides exhibited typical features of a collagen-like conformation. And thermal stabilities of the peptides were evaluated. The experimental results showed that the tricine branch did not enhance the thermal stability of the branched peptide compared with the unbranched one. They also studied if tricine-branched THPs could be used for the development of MMP substrates and inhibitors. The THP with DAE as a linker was incubated with MMP-1 at 25 °C. HPLC and Mass spectrometric analysis revealed that the THP behaved similarly to the unbranched substrate.

In a word, tricine-based branch reported represents the simplest synthetic scaffold for the convenient synthesis of covalently linked homomeric collagen-model THPs.

Edited by Suzhou Yacoo Science Co., Ltd.