Abstract
Insect glutathione S-transferases (GSTs) play important roles in insecticide/drug resistance and stress response. Medically, GSTs of house dust mites (Dermatophagoides pteronyssinus and Blomia tropicalis) and German cockroach (Blattella germanica) are human allergens. In this study, classes, isoforms and B-cell and allergenic epitopes of GST of American cockroach, Periplaneta americana, the predominant species in the tropics and subtropics were investigated for the first time. Enzymatically active native and recombinant Pamericana-GSTs bound to IgE in sera of all Pamericana allergic patients that were tested. By gel-based proteomics and multiple sequence alignments, the native GST comprises three isoforms of delta and sigma classes.