| RRC ID |
36035
|
| Author |
Kiyokawa E, Makino A, Ishii K, Otsuka N, Yamaji-Hasegawa A, Kobayashi T.
|
| Title |
Recognition of sphingomyelin by lysenin and lysenin-related proteins.
|
| Journal |
Biochemistry
|
| Abstract |
Lysenin is a sphingomyelin (SM)-specific toxin isolated from the coelomic fluid of the earthworm Eisenia foetida. Lysenin comprises a family of proteins together with lysenin-related protein 1 (LRP-1, lysenin 2) and LRP-2 (lysenin 3). In the present study, we characterized LRP-1 and LRP-2 together with lysenin using maltose-binding-protein-tagged recombinant proteins. LRP-2 specifically bound SM and induced hemolysis like lysenin. In contrast the binding and hemolytic activities of LRP-1 were 10 times less than those of lysenin and LRP-2. Lysenin and LRP-2 share 30 common sites of aromatic amino acids. Among them, only one position, phenylalanine 210, is substituted for isoleucine in LRP-1. The activity of LRP-1 was dramatically increased by introducing a single amino acid substitution of isoleucine 210 to phenylalanine, suggesting the importance of this aromatic amino acid in biological activities of lysenin and LRPs. The importance of aromatic amino acids was further indicated by a systematic tryptophan to alanine mutation of lysenin. Lysenin contains six tryptophan residues of which five are conserved in LRP-1 and -2. We showed that the conserved tryptophans but not the nonconserved one were required both in the recognition of SM and in the hemolytic activity of lysenin. Our results suggest the importance of tryptophan in the toxin function likely due to a direct recognition of SM or in maintaining the protein structure.
|
| Volume |
43(30)
|
| Pages |
9766-73
|
| Published |
2004-8-3
|
| DOI |
10.1021/bi049561j
|
| PMID |
15274631
|
| MeSH |
Amino Acid Sequence
Amino Acid Substitution / genetics
Animals
Carrier Proteins / chemistry
Cell Line, Tumor
Cells, Cultured
Cytotoxins / chemistry
Cytotoxins / genetics
Cytotoxins / metabolism
Hemolysis / genetics
Humans
Isoleucine / genetics
Maltose-Binding Proteins
Mice
Molecular Sequence Data
Oligochaeta*
Phenylalanine / genetics
Protein Binding / genetics
Proteins / chemistry*
Proteins / genetics
Proteins / metabolism*
Recombinant Proteins / chemistry
Recombinant Proteins / genetics
Recombinant Proteins / metabolism
Sphingomyelins / chemistry
Sphingomyelins / metabolism*
Structural Homology, Protein*
Toxins, Biological
Tryptophan / chemistry
Tryptophan / genetics
|
| IF |
2.865
|
| Times Cited |
55
|
|
WOS Category
|
BIOCHEMISTRY & MOLECULAR BIOLOGY
|
| Resource |
| DNA material |
pMAL/MBP-lysenin (RDB13958) |
