Purification, characterization and functional expression of a new peptide with an analgesic effect from Chinese scorpion Buthus martensii Karsch (BmK AGP-SYPU1)

In this study, a new peptide named BmK AGP‐SYPU1 with an analgesic effect was purified from the venom of Chinese scorpion Buthus martensi Karsch (BmK) through a four‐step chromatographic process. The mouse twisting test was used to identify the target peptides in every separation step. The purified BmK AGP‐SYPU1 was further qualified by RP‐HPLC and HPCE. The molecular mass determined by the MALDI‐4800‐TOF/TOF MS for BmK AGP‐SYPU1 was 7544 Da. Its primary structure of the N‐terminal was obtained using Edman degradation. The gene sequence of BmK AGP‐SYPU1 was cloned from the cDNA pool and genomic of scorpion glands, respectively, and then expressed in Escherichia coli. The sequence determination showed that BmK AGP‐SYPU1 was composed of 66 amino acid residues with a new primary structure. The metal chelating affinity column and cation exchange chromatography were used to purify the recombinant BmK AGP‐SYPU1. Consequently, the native and recombinant BmK AGP‐SYPU1 showed similar analgesic effects on mice as assayed using a mouse twisting model. These results suggested that BmK AGP‐SYPU1 is a new analgesic component found in the Chinese scorpion Buthus martensi Karsch. Copyright © 2010 John Wiley & Sons, Ltd.