CryoSeek II: Cryo-EM Analysis of Glycofibrils from Freshwater Reveals Well-structured Glycans Coating Linear Tetrapeptide Repeats

Overview

Journal Proc Natl Acad Sci U S A

Specialty Science

Date 2024 Dec 31

PMID 39739783

Authors

Tongtong Wang

Wenze Huang

Kui Xu

Yitong Sun

Qiangfeng Cliff Zhang

Chuangye Yan

Zhangqiang Li

Nieng Yan

Affiliations

Soon will be listed here.

Abstract

Despite the recent breakthrough in structure determination and prediction of proteins, the structural investigation of carbohydrates remains a challenge. Here, we report the cryo-EM analysis of a glycofibril found in the freshwater in the Tsinghua Lotus Pond. The fibril, which we name TLP-4, is made of a linear chain of tetrapeptide repeats coated with >4 nm thick glycans. In each repeat, two glycans are O-linked to a 3,4-dihydroxyproline and another glycan attaches to the adjacent Ser or Thr. The fibril structure is entirely maintained through glycan packing. Bioinformatic analysis confirms the conservation of the TLP-4 repeats across species, suggesting the existence of a large number of glycofibrils to be discovered. Our findings not only provide valuable insights into the structural roles of glycans in bio-assemblies but also demonstrate the potential of our recently formulated research strategy of CryoSeek to find bioentities and establish prototypes for structural studies of carbohydrates.

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