1. Department of Zoology and Entomology, Forestry and Agricultural Biotechnology InstituteUniversity of Pretoria Pretoria 0002 South Africa
2. Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, Centre for Microbial Ecology and GeneticsUniversity of Pretoria Pretoria 0002 South Africa
3. Department of BiochemistryMax Planck Institute for Chemical Ecology Jena 07745 Germany