1. Department of Molecular Biology of Plant-Microbe Interactions; Albrecht-von-Haller Institute of Plant Sciences, Schwann-Schleiden Research Center for Molecular Cell Biology, Georg-August-Universität Göttingen; Julia-Lermontowa-Weg 3 Göttingen 37077 Germany
2. Department of Organismic Interactions; Max Planck Institute for Terrestrial Microbiology; Karl-von-Frisch Straße 10 Marburg 35043 Germany
3. Department of Plant Biotechnology; National Research Centre; Cairo 12311 Egypt
4. Department of Microbial Genetics; Institute of Applied Microbiology, Aachen Biology and Biotechnology, RWTH Aachen University; Worringer Weg 1 Aachen 52074 Germany