The strains are abbreviated as WSM419 for Sinorhizobium medicae WSM419, MAFF303099 for Mesorhizobium loti MAFF303099, USDA110 for Bradyrhizobium japonicum USDA110, and NGR234 for Sinorhizobium sp. NGR234. The original number means the number of proteins collected from the rhizobial strains. For MAFF303099 and NGR234, the numbers are the total numbers of proteins on both the chromosome and plasmids. The third column lists the numbers of sequences that have the tts motif in their promoters. The fourth column records the numbers of candidate effectors predicted by the SVM.