Biomaterial Database

Cleavage of the protein III and major iron-regulated protein of Neisseria gonorrhoeae by lysosomal cathepsin G. 1987

W M Shafer, and S A Morse

Department of Microbiology and Immunology, School of Medicine, Emory University, Atlanta, GA 30322.

Incubation of either 125I-labelled or unlabelled Neisseria gonorrhoeae with enzymically active preparations of human polymorphonuclear leucocyte lysosomal cathepsin G revealed that surface-exposed outer-membrane proteins were susceptible to proteolytic modification. Electroimmunoblotting experiments confirmed that outer-membrane protein III (PIII) and the major iron-regulated protein (MIRP), two conserved gonococcal proteins, were cleaved by cathepsin G. A direct relationship was observed between susceptibility to the antibacterial properties of cathepsin G and cleavage of PIII among isogenic strains differing in their level of resistance to the bactericidal activity of cathepsin G. Although the antibacterial property of cathepsin G is known to be independent of serine-esterase activity, the data suggest that gonococcal outer-membrane proteins are involved in the binding of cathepsin G, and that variation in the level of resistance reflects the degree to which target outer-membrane proteins such as PIII are exposed.

UI	MeSH Term	Description	Entries
D007158	Immunologic Techniques	Techniques used to demonstrate or measure an immune response, and to identify or measure antigens using antibodies.	Antibody Dissociation,Immunologic Technic,Immunologic Technics,Immunologic Technique,Immunological Technics,Immunological Techniques,Technic, Immunologic,Technics, Immunologic,Technique, Immunologic,Techniques, Immunologic,Antibody Dissociations,Dissociation, Antibody,Dissociations, Antibody,Immunological Technic,Immunological Technique,Technic, Immunological,Technics, Immunological,Technique, Immunological,Techniques, Immunological
D009344	Neisseria gonorrhoeae	A species of gram-negative, aerobic bacteria primarily found in purulent venereal discharges. It is the causative agent of GONORRHEA.	Diplococcus gonorrhoeae,Gonococcus,Gonococcus neisseri,Merismopedia gonorrhoeae,Micrococcus der gonorrhoe,Micrococcus gonococcus,Micrococcus gonorrhoeae
D002403	Cathepsins	A group of lysosomal proteinases or endopeptidases found in aqueous extracts of a variety of animal tissues. They function optimally within an acidic pH range. The cathepsins occur as a variety of enzyme subtypes including SERINE PROTEASES; ASPARTIC PROTEINASES; and CYSTEINE PROTEASES.	Cathepsin
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
D001345	Autoradiography	The making of a radiograph of an object or tissue by recording on a photographic plate the radiation emitted by radioactive material within the object. (Dorland, 27th ed)	Radioautography
D001425	Bacterial Outer Membrane Proteins	Proteins isolated from the outer membrane of Gram-negative bacteria.	OMP Proteins,Outer Membrane Proteins, Bacterial,Outer Membrane Lipoproteins, Bacterial
D012697	Serine Endopeptidases	Any member of the group of ENDOPEPTIDASES containing at the active site a serine residue involved in catalysis.	Serine Endopeptidase,Endopeptidase, Serine,Endopeptidases, Serine
D056649	Cathepsin G	A serine protease found in the azurophil granules of NEUTROPHILS. It has an enzyme specificity similar to that of chymotrypsin C.