Biomaterial Database

Cysteine protease activity of streptococcal pyrogenic exotoxin B. 1994

Y Ohara-Nemoto, and M Sasaki, and M Kaneko, and T Nemoto, and M Ota

Department of Microbiology, School of Dentistry, Iwate Medical University, Morioka, Japan.

Streptococcal pyrogenic exotoxin B (SPE B) was purified and its protease and mitogenic activities were investigated. The apparent molecular mass of SPE B purified in the presence of iodoacetic acid was 42 kDa, whereas 29-kDa SPE B was predominant without the reagent. A polyclonal antibody raised against the 29-kDa species reacted with both species, indicating that the 42-kDa species was a precursor of the 29-kDa entity. Both the 42- and 29-kDa species enhanced [3H]thymidine incorporation into human peripheral blood mononuclear cells, whereas neither had any effect on T cell depleted mononuclear cells. The 29-kDa SPE B possessed caseinolytic activity, with an optimal pH of 8, and the activity was specifically suppressed by the antibody. A group of cysteine protease inhibitors, but no serine-, metallo-, or acidic-protease inhibitors, limited the protease activity, whereas dithiothreitol increased the activity. The DNA sequence around a putative active cysteine residue was identical among the speB genes from Streptococcus pyogenes R70, NY-5, and T19. Taken together, these results indicate that SPE B is identical to a cysteine protease, streptopain (EC 3.4.22.10).

UI	MeSH Term	Description	Entries
D007963	Leukocytes, Mononuclear	Mature LYMPHOCYTES and MONOCYTES transported by the blood to the body's extravascular space. They are morphologically distinguishable from mature granulocytic leukocytes by their large, non-lobed nuclei and lack of coarse, heavily stained cytoplasmic granules.	Mononuclear Leukocyte,Mononuclear Leukocytes,PBMC Peripheral Blood Mononuclear Cells,Peripheral Blood Human Mononuclear Cells,Peripheral Blood Mononuclear Cell,Peripheral Blood Mononuclear Cells,Leukocyte, Mononuclear
D008565	Membrane Proteins	Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.	Cell Membrane Protein,Cell Membrane Proteins,Cell Surface Protein,Cell Surface Proteins,Integral Membrane Proteins,Membrane-Associated Protein,Surface Protein,Surface Proteins,Integral Membrane Protein,Membrane Protein,Membrane-Associated Proteins,Membrane Associated Protein,Membrane Associated Proteins,Membrane Protein, Cell,Membrane Protein, Integral,Membrane Proteins, Integral,Protein, Cell Membrane,Protein, Cell Surface,Protein, Integral Membrane,Protein, Membrane,Protein, Membrane-Associated,Protein, Surface,Proteins, Cell Membrane,Proteins, Cell Surface,Proteins, Integral Membrane,Proteins, Membrane,Proteins, Membrane-Associated,Proteins, Surface,Surface Protein, Cell
D008934	Mitogens	Substances that stimulate mitosis and lymphocyte transformation. They include not only substances associated with LECTINS, but also substances from streptococci (associated with streptolysin S) and from strains of alpha-toxin-producing staphylococci. (Stedman, 25th ed)	Mitogen,Phytomitogen,Phytomitogens
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D003546	Cysteine Endopeptidases	ENDOPEPTIDASES which have a cysteine involved in the catalytic process. This group of enzymes is inactivated by CYSTEINE PROTEINASE INHIBITORS such as CYSTATINS and SULFHYDRYL REAGENTS.
D004229	Dithiothreitol	A reagent commonly used in biochemical studies as a protective agent to prevent the oxidation of SH (thiol) groups and for reducing disulphides to dithiols.	Cleland Reagent,Cleland's Reagent,Sputolysin,Clelands Reagent,Reagent, Cleland,Reagent, Cleland's
D005098	Exotoxins	Toxins produced, especially by bacterial or fungal cells, and released into the culture medium or environment.	Exotoxin
D005798	Genes, Bacterial	The functional hereditary units of BACTERIA.	Bacterial Gene,Bacterial Genes,Gene, Bacterial