mr1e, a conotoxin from Conus marmoreus with a novel disulfide pattern
Authors: Wang, Yanfang1; Shao, Xiaoxia1; Li, Min1; Wang, Sumin2; Chi, Chengwu; Wang, Chunguang
Source: Acta Biochimica et Biophysica Sinica, Volume 40, Number 5, May 2008 , pp. 391-396(6)
Publisher: Blackwell Publishing
- Free Content
- New Content
- Subscribed Content
- Free Trial Content
Abstract:
Conotoxins are well known for their highly variable structures and functions. Here we report the identification of a novel conotoxin named mr1e from Conus marmoreus. mr1e is composed of 11 amino acid residues cross-linked by two disulfide bonds (CCHSSWCKHLC). The spacing of intercysteine loops in mr1e is exactly the same as that in α4/3 conotoxins. However, the native mr1e peptide co-eluted on reverse-phase HPLC with the regioselectively synthesized ribbon disulfide linkage isomer (C1-C4, C2-C3) but not the globular linkage isomer (C1-C3, C2-C4). Although this peptide has the same disulfide connectivity as the χ-conotoxins, their sequences do not share significant homology. Thus, mr1e could be defined as a novel conotoxin family. By intracranial injection into mice, mr1e showed an excitatory effect. The characterization of mr1e certainly enriches our understanding of conotoxins, and also opens an avenue for further structural and functional investigation.Keywords: conotoxin; Conus marmoreus; disulfide connectivity; mr1e
Document Type: Research article
DOI: 10.1111/j.1745-7270.2008.00414.x
Affiliations: 1: Institute of Protein Research, Tongji University, Shanghai 200092, China 2: School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
- Free Content
- New Content
- Subscribed Content
- Free Trial Content
Click here for Page Help