CryoSeek（酷寻）——利用冷冻电镜开启结构生物学发现的新范式
王彤彤，李张强*，颜 宁*
（1. 清华大学生命科学学院，北京 100084；2. 深圳医学科学院，深圳 广东 518107；3. 深圳湾实验室，深圳 广东 518132）
摘 要 随着冷冻电镜技术的突破以及AI辅助的结构预测和自动模型搭建算法的发展，结构生物学正在经历由目标结构解析到结构引导的未知生物大分子发现的范式转变。本综述回顾了冷冻电镜的发展历史，并介绍CryoSeek（酷寻）研究策略：利用冷冻电镜探索自然环境中完全未知的生物大分子结构。作者从清华大学的荷塘采集水样作为CryoSeek研究的起点，经过过滤和富集后，通过冷冻电镜观察到多种纤维结构，并获得了两种相似螺旋TLP-1a/b的高分辨率图谱，其原子模型由AI辅助的CryoNet自动搭建。结构分析表明TLP-1a/b通过供体链交换模式组装。结构比对和序列分析显示TLP-1a/b可能是未鉴定的细菌菌毛。以上研究表明高分辨率结构解析引导并推动了未知生物大分子的识别，标志着结构生物学研究的新兴范式的建立。
关键词 冷冻电镜；结构生物学；CryoSeek；纤维；供体链交换
中图分类号：Q-1, Q-31, Q6-3, Q6-3, Q6-3 文献标识码：ADoi:10.3969/j.issn.1000-6281.2025.01.015
CryoSeek—a new paradigm in structural biology using Cryo-EM to discover uncharacterized bio-entities
WANG Tongtong，LI Zhangqiang*，YAN Ning*
(1. School of Life Sciences, Tsinghua University, Beijing 100084；2. Shenzhen Medical Academy of Research and Translation, Guangming District, Shenzhen Guangdong 518107；3. Shenzhen Bay Laboratory, Guangming District, Shenzhen Guangdong 518132, China)
Abstract With the advancement of cryo-electron microscopy (Cryo-EM), AI-facilitated structure prediction, and automated model building, structural biology is shifting from target-specific structural analysis to structure- Guangdong, China)guided discovery of unknown bio-entities. This review brief summarizes the history of Cryo-EM and introduces a new research strategy, named CryoSeek, which uses Cryo-EM to explore the structures of entirely unknown bio-entities in natural environments or native samples. We initiated CryoSeek by collecting water samples from the Tsinghua Lotus Pond. After filtration and enrichment, various fibril structures were observed using Cryo-EM, and high-resolution EM maps of two similar helices, TLP-1a and TLP-1b, were obtained. Their structures were automatically built using AI-facilitated software CryoNet. Structural analysis revealed that TLP-1a/b assemble via a donor-strand exchange mechanism. Structural comparison and sequence analysis suggest that TLP-1a/b may represent uncharacterized bacterial pili. This result highlights the role of high-resolution structural analysis in guiding and driving the identification of unknown bio-entities, signifying a new emerging paradigm in structural biology research.
Keywords Cryo-EM；structural biology；CryoSeek；fibril；donor-strand exchange
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