The amino acid sequence of an atypical single‐chain lectin from seeds of Lathyrus sphaericus (Retz)

FEBS Letters

Richardson, Michael¹  Rougé, Pierre²  Yarwood, Alan¹ 

[1] Department of Botany, University of Durham, Science Laboratories, South Road, Durham DH1 3LE, England;Laboratoire de Botanique et Biologie Cellulaire, Faculté des Sciences Pharmaceutiques, Université Paul Sabatier, 35 chemin des Maraîchers, 31062 Toulouse, France

关键词: Lectin;    Single chain;    Amino acid sequence;    Homology;    (Lathyrus sphaericus);   

DOI  :  10.1016/0014-5793(87)80773-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The major lectin from seeds of Lathyrus spaericus (Retz) was purified by fractional precipitation with (NH₄)₂SO₄, affinity chromatography on Sephadex G-100, chromatofocusing on PBE 94 and gel filtration on Biogel P-100 in the presence of 6 M guanidine HCl. The protein was found to be atypical of the lectins found in the Vicieae in that it was a dimer of two identical single polypeptide chains whose monomer molecular mass was estimated to be 27–28 kDa by SDS-PAGE. The complete amino acid sequence of the monomer was determined by analysis of peptides derived from the protein by digestion with trypsin, chymotrypsin, pepsin, the S.aureus V8 protease and a lysine-specific protease from Lysobacter enzymogenes, as well as fragments produced by cleavage with iodosobenzoic acid. The polypeptide chain contained 244 amino acids and exhibited overlapping homology with the β (heavy) and α (light) chains of the two-chain lectins found in other Lathyrus species and in genera belonging to the tribe Vicieae, but was unusual in containing additional amino acids at the N-terminus and in two other regions (insertions), some deletions, and alterations in 44 previously conserved amino acid positions.

【 授权许可】

Unknown