γ‐Purothionins: amino acid sequence of two polypeptides of a new family of thionins from wheat endosperm

FEBS Letters

Rocher, Asuncion¹  Mendez, Enrique¹  Colilla, Francisco J.¹ 

[1] Servicio de Endocrinologia, Hospital Ramon y Cajal, 28034 Madrid, Spain

关键词: Wheat thionin;    Amino acid sequence;    γ-Purothionin;    γ1-P and γ2-P;    γ1- and γ2-purothionins;    RP-HPLC;    reversed-phase high-performance liquid chromatography;    SDSPAGE;    sodium dodecyl sulfate polyacrylamide gel electrophoresis;    Ch;    chymotrypsin;   

DOI  :  10.1016/0014-5793(90)81265-P

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Two homologous sulfur-rich basic polypeptides form wheat endosperm, so-called γ₁-purothionin and γ₂-purothionin, are described. Purification involves extraction with volatile solvents and ammonium bicarbonate fractionation followed by reversed-phase high-performance liquid chromatography. The complete primary structure of these two polypeptides has been determined by automatic degradation of the intact, S-carboxymethylated γ-purothionins and peptides obtained by enzymatic cleavage. γ₁-Purothionin and γ₂-purothionin consist of 47 amino acids with an assessed molecular weight of 5239 and 5151 Da, respectively and 8 cysteines organized in 4 disulfide bridges. They present a high degree of homology among themselves (89% of identity) and are the first two thionin-like polypeptides, so-called y-thionins, described from wheat endosperm.

【 授权许可】

Unknown