Circular map of the pSymA megaplasmid of S. meliloti, showing FRT-flanked regions generated in this study. Solid-line regions, Flp transconjugants recovered and deletions (Δ) confirmed. Dotted-line regions, Flp transconjugants not recovered. Predicted TA encoded proteins on the pSymA megaplasmid: 1, Sma5001; 2, Sma0191/Sma0193; 3, Sma0285/Sma0286; 4, Sma0319; 5, Sma0453; 6, Sma0471/Sma0473; 7, Sma0545/Sma0548; 8, Sma0572; 9, Sma0592/Sma0594; 10, Sma0917; 11, Sma5006/Sma5007; 12, Sma0967; 13, Sma0981; 14, Sma1056; 15, Sma1076; 16, Sma1253; 17, Sma5008; 18, Sma1413; 19, Sma1455/Sma1456; 20, Sma1476; 21, Sma1497; 22, Sma1725; 23, Sma1749; 24, Sma1770; 25, Sma1822; 26, Sma1823; 27, Sma1825; 28, Sma1924; 29, Sma1990; 30, Sma2105; 31, Sma2133; 32, Sma2151; 33, Sma2163; 34, Sma2231; 35, Sma2253/Sma2255; 36, Sma2273/Sma2275; 37, Sma2279/Sma2281; 38, Sma2315; 39, Sma2319.