Patent ID: 7217793

Claim:
An isolated or purified protein consisting of one of the following amino acid sequences: (1) amino acids 161–297; 146–297; 131–297, or 118–297 of Lysenin-1; (2) an amino acid sequence derived from amino acids 161–297, 146–297, 131–297, or 118–297 of Lysenin 1 by substitution, deletion, and/or addition of 1 to 10 amino acids, wherein the 187 th , 245 th , and 291 st tryptophan residues of the amino acid sequence derived from amino acids 161–297, 146–297, 131–297, or 118–297 of Lysenin-1 are not deleted or substituted, which specifically recognizes sphingomyelin and has cytotoxicity lower than that of Lysenin 1, as measured by hemolysis.