title: Localization of biologically important regions on toxic shock syndrome toxin 1.
abstract: Toxic shock syndrome toxin 1 (TSST-1) contains a long central alpha helix that forms the base of two grooves on opposite sides of the molecule. Previous studies indicated that residues 132, 135, and 140 along the back of the central alpha helix are important in the biological activities. We made mutations of additional central alpha-helix residues exposed along this groove on the back of TSST-1. The proteins were purified, shown not to have gross alteration in structure, and tested for both superantigenicity and ability to elicit lethal TSS, using the superantigenicity, likely to because of alteration in T-cell receptor binding. Mutants H135A, Q136A, and E132K/ Q136K lost the ability to induce lethal TSS. The mutant Q136A was most increasing because it was superantigenic, yet nonlethal.
authors.affiliation: Department of Microbiology, University of Minnesota Medical School, Minneapolis 55455, USA.
authors.forename: D L
authors.initials: DL
authors.lastname: Murray
authors.forename: C A
authors.initials: CA
authors.lastname: Earhart
authors.forename: D T
authors.initials: DT
authors.lastname: Mitchell
authors.forename: D H
authors.initials: DH
authors.lastname: Ohlendorf
authors.forename: R P
authors.initials: RP
authors.lastname: Novick
authors.forename: P M
authors.initials: PM
authors.lastname: Schlievert
mesh_terms: D000818:Animals; D001427:Bacterial Toxins; D004252:DNA Mutational Analysis; D004305:Dose-Response Relationship, Drug; D004768:Enterotoxins / Q000235:genetics / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D017433:Protein Structure, Secondary; D011817:Rabbits; D012772:Shock, Septic; D013211:Staphylococcus aureus / Q000276:immunology*; D013329:Structure-Activity Relationship; D018089:Superantigens / Q000235:genetics / Q000494:pharmacology*
chemical_list: D001427:Bacterial Toxins; D004768:Enterotoxins; D018089:Superantigens; C030107:enterotoxin F, Staphylococcal