An mRNA-display derived cyclic peptide scaffold reveals the substrate binding interactions of an N-terminal cysteine oxidase

• 全文链接

mRNA展示衍生的环肽支架揭示了N端半胱氨酸氧化酶的底物结合相互作用

关键词：

来源：

Nature Communications

全文链接：

//agri.nais.net.cn/topic/downloadFile/e5db1ee9-f9ec-450e-8d8b-117f1e8008db

来源地址：

https://www.nature.com/articles/s41467-025-59960-3

资源所属：

饲料用酶工程

类型：

学术文献

语种：

英语

原文发布日期：

2025-05-22

摘要：

N-terminal cysteine oxidases (NCOs) act as enzymatic oxygen (O2) sensors, coordinating cellular changes to hypoxia in animals and plants. They regulate the O2-dependent stability of proteins bearing an N-terminal cysteine residue through the N-degron pathway. Despite their important role in hypoxic adaptation, which renders them potential therapeutic and agrichemical targets, structural information on NCO substrate binding remains elusive. To overcome this challenge, we employed a unique strategy by which a cyclic peptide inhibitor of the mammalian NCO, 2-aminoethanethiol dioxygenase (ADO), was identified by mRNA display and used as a scaffold to graft substrate moieties. This allowed the determination of two substrate analogue-bound crystal structures of ADO. Key binding interactions were revealed, including bidentate coordination of the N-terminal residue at the metal cofactor. Subsequent structure guided mutagenesis identified aspartate-206 as an essential catalytic residue, playing a role in reactive oxygen intermediate orientation or stabilisation. These findings provide fundamental information on ADO substrate interactions, which can elucidate enzyme mechanism and act as a platform for chemical discovery.