The C‐terminal region of the S component of Staphylococcal leukocidin is essential for the biological activity of the toxin

FEBS Letters

Nariya, Hirofumi¹  Kamio, Yoshiyuki¹  Izaki, Kazuo¹ 

[1] Department of Applied Biological Chemistry, Faculty of Agriculture, Tohoku University, Amamiya-machi, Aoba-ku, Sendai 981, Japan

关键词: Staphylococcal leukocidin;    S component;    Monosialoganglioside GM1;    S;    S component of leukocidin;    F;    F component of leukocidin;    GM1;    monosialoganglioside GM1;    SDS-PAGE;    sodium dodecylsulfate polyacrylamide gel electrophoresis;    HPLC;    high-performance liquid chromatography;   

DOI  :  10.1016/0014-5793(93)80225-J

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The Staphylococcal toxin leukocidin consists of two protein components, F and S. From a culture medium of Staphylococcus aureus RIMD 310925, we isolated a truncated form of S (LS₂), of which the C-terminal 17-residue segment is missing. Unlike intact S, LS₂ showed neither leukocytolytic activity in the presence of F nor affinity for monosialoganglioside G_M1 (G_M1). When excited at 280 nm, both S and LS₂ exhibited intrinsic tryptophan fluorescence with an emission maximum at 318 nm. Upon binding to G_M1, the emission maximum of S underwent a blue shift to 310 nm, whereas no change in fluorescence took place on mixing G_M1 with LS₂. We conclude that the C-terminal region of S is essential for its biological activity as well as for its binding to G_M1 and that this binding is accompanied by a conformational change of the S protein.

【 授权许可】

Unknown