Biomaterial Database

Sterol structural requirements for inhibition of streptolysin O activity. 1974

K C Watson, and E J Kerr

Reduced streptolysin O, a toxin produced by certain beta-haemolytic streptococci, lyses human erythrocytes. The reaction is inhibited by cholesterol at concentrations of about 1.0mug/ml. Other sterols inhibit the lysin and there is a specific requirement for a 3beta-hydroxyl group. Inhibition was obtained with 3beta-hydroxychol-5-en-24-oic acid, containing a hydrophilic group at C-24. The mode of inhibition is likely to involve attachment to the fixation site of the lysin which attaches the molecule to cell membranes, probably to membrane cholesterol. A second streptolysin site, concerned in the final haemolytic event, may also be involved. Inhibitors of the latter site have not been characterized, other than antibody with specificity for the site.

UI	MeSH Term	Description	Entries
D002776	Cholestanes	Derivatives of the saturated steroid cholestane with methyl groups at C-18 and C-19 and an iso-octyl side chain at C-17.
D002784	Cholesterol	The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.	Epicholesterol
D003897	Desmosterol	An intermediate in the synthesis of cholesterol.	24-Dehydrocholesterol,Demosterol,24 Dehydrocholesterol
D004912	Erythrocytes	Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.	Blood Cells, Red,Blood Corpuscles, Red,Red Blood Cells,Red Blood Corpuscles,Blood Cell, Red,Blood Corpuscle, Red,Erythrocyte,Red Blood Cell,Red Blood Corpuscle
D006461	Hemolysis	The destruction of ERYTHROCYTES by many different causal agents such as antibodies, bacteria, chemicals, temperature, and changes in tonicity.	Haemolysis,Extravascular Hemolysis,Intravascular Hemolysis,Extravascular Hemolyses,Haemolyses,Hemolyses, Extravascular,Hemolyses, Intravascular,Hemolysis, Extravascular,Hemolysis, Intravascular,Intravascular Hemolyses
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D012855	Sitosterols	A family of sterols commonly found in plants and plant oils. Alpha-, beta-, and gamma-isomers have been characterized.
D013261	Sterols	Steroids with a hydroxyl group at C-3 and most of the skeleton of cholestane. Additional carbon atoms may be present in the side chain. (IUPAC Steroid Nomenclature, 1987)	Sterol
D013301	Streptolysins	Exotoxins produced by certain strains of streptococci, particularly those of group A (STREPTOCOCCUS PYOGENES), that cause HEMOLYSIS.	Streptolysin
D013329	Structure-Activity Relationship	The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.	Relationship, Structure-Activity,Relationships, Structure-Activity,Structure Activity Relationship,Structure-Activity Relationships