Biomaterial Database

Assembly of Staphylococcus aureus gamma-hemolysin into a pore-forming ring-shaped complex on the surface of human erythrocytes. 1997

N Sugawara, and T Tomita, and Y Kamio

Department of Applied Biological Chemistry, Faculty of Agriculture, Tohoku University, Aoba-Ku, Sendai, Japan.

Staphylococcal gamma-hemolysin consists of Hlg1 (or Luk F) of 34 kDa and Hlg2 of 32 kDa, which cooperatively lyse human erythrocytes. Since gamma-hemolysin caused swelling of human erythrocytes prior to lysis, we studied pore-forming nature of the toxin by use of polyethylene glycols as osmotic protectants and determined the functional diameter of the pore. To elucidate the molecular architecture of the membrane pore formed by gamma-hemolysin, we solubilized the pore complex with 2% sodium dodecyl sulfate, separated it from erythrocyte membrane proteins by sucrose gradient ultracentrifugation, and observed the isolated complex under an electron microscope. Our data showed that Hlg1 and Hlg2 of gamma-hemolysin assemble into a ring-shaped 195 kDa complex in a molar ratio of 1 : 1, which may form a membrane pore with a functional diameter of 2.1-2.4 nm.

UI	MeSH Term	Description	Entries
D002462	Cell Membrane	The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.	Plasma Membrane,Cytoplasmic Membrane,Cell Membranes,Cytoplasmic Membranes,Membrane, Cell,Membrane, Cytoplasmic,Membrane, Plasma,Membranes, Cell,Membranes, Cytoplasmic,Membranes, Plasma,Plasma Membranes
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
D006460	Hemolysin Proteins	Proteins from BACTERIA and FUNGI that are soluble enough to be secreted to target ERYTHROCYTES and insert into the membrane to form beta-barrel pores. Biosynthesis may be regulated by HEMOLYSIN FACTORS.	Hemolysin,Hemolysins,Hemalysins,Proteins, Hemolysin
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001426	Bacterial Proteins	Proteins found in any species of bacterium.	Bacterial Gene Products,Bacterial Gene Proteins,Gene Products, Bacterial,Bacterial Gene Product,Bacterial Gene Protein,Bacterial Protein,Gene Product, Bacterial,Gene Protein, Bacterial,Gene Proteins, Bacterial,Protein, Bacterial,Proteins, Bacterial
D001427	Bacterial Toxins	Toxic substances formed in or elaborated by bacteria; they are usually proteins with high molecular weight and antigenicity; some are used as antibiotics and some to skin test for the presence of or susceptibility to certain diseases.	Bacterial Toxin,Toxins, Bacterial,Toxin, Bacterial