Primary structure of two cytolysin isoforms from Stichodactyla helianthus differing in their hemolytic activity.
Sticholysin I (St-I) and sticholysin II (St-II) are cytolysins purified from the sea anemone Stichodactyla helianthus with a high degree of sequence identity (93%) but clearly differenced in their hemolytic activity. In order to go further into the structural determinants for the different behavior of St-I and St-II, we report here the complete amino acid sequences and the consensus secondary structure prediction of both proteins. The complete determination of St-II primary structure confirms the partial revision of cytolysin III amino acid sequence. All nonconservative changes between St-I and St-II are located at the N-terminal. According to our prediction these changes could be located at the same face of an alpha-helix during pore formation events and could account for the observed differences in hemolytic activity between St-I and St-II.
Huerta
V
V
Physical-Chemistry Division, Protein Structure Department, Center for Genetic Engineering and Biotechnology, P.O. Box 6162, Havana City, Cuba.
Morera
V
V
Guanche
Y
Y
Chinea
G
G
González
L J
LJ
Betancourt
L
L
Martínez
D
D
Alvarez
C
C
Lanio
M E
ME
Besada
V
V
D000595:Amino Acid Sequence; D000818:Animals; D003064:Cnidarian Venoms / Q000737:chemistry* / Q000633:toxicity; D006460:Hemolysin Proteins / Q000737:chemistry* / Q000633:toxicity; D006461:Hemolysis / Q000187:drug effects*; D008969:Molecular Sequence Data; D009930:Organic Chemicals; D017433:Protein Structure, Secondary
D003064:Cnidarian Venoms; D006460:Hemolysin Proteins; D009930:Organic Chemicals; C404794:sticholysin II; C121348:stycholysin I