Application

Streptolysin O is a toxin secreted by Streptococcus pyogenes and is a prototype member of poreforming bacterial cytolysins. It is used permeabilize cell membranes to permit cellular uptake of large or charged molecules. It is used to study macromolecule delivery. It is a potential anticancer agent and is used to study suicide cancer gene therapy.

Used to create holes (reversible pores) in cholesterol-enriched plasma membranes of eukaryotic cells allowing selective permeabilization with molecules such as proteins (up to 100 kDa) and siRNAs.

Permeabilizes membranes to permit cellular uptake of large or charged molecules.

Biochem/physiol Actions

Thiol-activated toxin that permeabilizes animal cell membranes. The protein binds as a monomer to membrane cholesterol and subsequently polymerizes into large arc- and ring-shaped structures surrounding pores of >12 nm.

Streptolysin O possesses a single polypeptide chain with a molecular weight of f62 kDa. Streptolysin O binds to membrane cholesterol and oligomerizes to create a ring structure that consists of 45 to 50 units. The ring structure inserts into the membrane to make a large pore (25 to 30 nm), which DNA, RNA, peptides and proteins may pass. It is thiol-activated. It is inhibited by allicin, an active component of garlic.

Other Notes

Keep container tightly closed in a dry and well-ventilated place. Keep in a dry place

Packaging

25KU

Physical form

Lyophilized powder containing Tris buffer salts, sodium azide, PMSF, and EDTA.

Unit Definition

One unit will cause 50% lysis of 2% red blood cell suspensions in phosphate buffered saline, pH 7.4, after incubation at 37 °C for 30 min.