1. Center for Structural Molecular Biology, BioNMR Laboratory, LNLS, Campinas, SP, Brazil, Center of Study of Social Insects, Department of Biology, Institute of Biosciences, UNESP, Rio Claro, SP, Brazil, Center for Applied Toxicology-CEPID-FAPESP, Institute Butantan, São Paulo, SP, Brazil, Department of Physics, IBILCE, UNESP, São José do Rio Preto, SP, Brazil, and Department of Experimental Medicine, Section of Chemistry and Structural Biochemistry, University of Parma, Parma, Italy