The analysis of the atomic structure of OST is a major breakthrough in sugar biology.

In a new study, researchers from the Wenandel Institute in the United States have revealed the atomic structure of a molecular complex used to modify proteins, which could pave the way for the development of new drugs to treat cancer and many other diseases.
related findings published online January 22, 2018 in the journal Nature with the headline "The atomic structure of a eukaryotic oligosaccharyltransferase complex".
this compound, called oligosaccharyltransferase (Oligosaccharyltransferase, OST), plays a key role in protein glycogenesis, a widely existing cellular process that is closely related to many functions in the body.
its role is to add a sugar molecule called polysaccharide to the protein, affecting the shape of these proteins and thus their function. "The analysis of the atomic structure of OST is a major breakthrough in sugar biology," said Dr. Huilin Li, a communications author at the
paper and a professor at the Wenander Institute.
as a key enzyme in n-connected polysaccharides biosynthesis pathways, OST plays an important role in both health and disease.
We hope these findings will lead people to develop life-changing drugs to treat cancer and many other diseases.
"most oST-modified proteins are secreted out of the cell or embedded in the cell's surface membrane, where they act as a channel for the cell to connect with its environment."
, for example, their exposure to cell environments and the presence of polysaccharides make them ideal targets for the development of new drugs that often use the specific chemical characteristics of polysaccharides to destroy cancer cells.
although OST was discovered decades ago, its structure is still unclear.
in the new study, the researchers parsed the atomic structure of OST from bread yeast, a simple and elegant biomedical research model.
different from other compounds assembled through protein interactions, the eight membrane proteins that make up OST are largely "bonded" together by the seven phospholipid molecules located at the center of its structure.
these lipids make it difficult to purify this compound for structural analysis. "The complexity and novelty of the OST structure is very significant," said Dr. Lin Bai, a senior researcher at Li Labs, the first author of the
paper.
this structure is the result of more than a decade of research and provides an important clear explanation and deep understanding of the cellular processes that typically affect half of the protein in the human body.
" this structure suggests the functional role of its eight component proteins, which have evolved over billions of years and are recruited into this catalytic core enzyme.
the researchers found some of these proteins to identify donor substrates or receptor proteins, while the remaining proteins coordinate protein synthesis and protein transport complex--- processes that are essential for life support.
this structure also reveals key reaction sites that may be targeted with drugs designed to correct dysfunction in diseases such as cancer.
OST is the third molecule at the Venander Institute to successfully observe imaging using the state-of-the-art David Van Andel Advanced Cryo-Electron Microscopy Suite.
(biovalleybioon.com) References: Lin Bai, Tong Wang, Gongpu Zhao et al. The atomic structure of a eukaryotic oligos ac charyl transferase complex. Nature, Published online: 22 January 2018, doi: 10.1038/nature25755.