Tyrosine 331 and phenylalanine 334 in Clostridium perfringens α‐toxin are essential for cytotoxic activity

FEBS Letters

Jayasekeera, Pramukh²  Lingard, Bryan²  Titball, Richard W.²  Flores-Diaz, Marietta⁴  Bullifent, Helen L.²  Crane, Dennis³  Alape-Giron, Alberto⁴  Jepson, Marie²  Moss, David¹ 

[1] Department of Crystallography, Birkbeck College, Malet St., London WCIE 7HX, UK;Defence Evaluation Research Agency, CBD Porton Down, Salisbury, UK;National Institute for Biological Standards and Control, Blanche Lane, South Mimms, UK;Microbiology and Tumor Biology Center, Karolinska Institutet, Stockholm, Sweden

关键词: Phospholipase C;    Membrane binding;    Site-directed mutant;   

DOI  :  10.1016/S0014-5793(01)02385-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Differences in the biological properties of the Clostridium perfringens phospholipase C (α-toxin) and the C. bifermentans phospholipase C (Cbp) have been attributed to differences in their carboxy-terminal domains. Three residues in the carboxy-terminal domain of α-toxin, which have been proposed to play a role in membrane recognition (D₂₆₉, Y₃₃₁ and F₃₃₄), are not conserved in Cbp (Y, L and I respectively). We have characterised D₂₆₉Y, Y₃₃₁L and F₃₃₄I variant forms of α-toxin. Variant D₂₆₉Y had reduced phospholipase C activity towards aggregated egg yolk phospholipid but increased haemolytic and cytotoxic activity. Variants Y₃₃₁L and F₃₃₄I showed a reduction in phospholipase C, haemolytic and cytotoxic activities indicating that these substitutions contribute to the reduced haemolytic and cytotoxic activity of Cbp.

【 授权许可】

Unknown