Accessing and Identification of Novel Environmental Alleles of the ACC Deaminase Domain Region through a Competition Assay

Rhizosphere soil samples from four Maize inbred lines (Oh43, MS71, M37W, and NC358) were collected from a field in Missouri, USA, in 2010. PCR reactions, pooled DNA extracted from all four lines, used custom primers a2F 5'- GSAACAAGACGCGCAAG-3' and a2R 5'-CACSAGCACGCACTTCATG-3', to amplify a 37 amino acid region from the full-length accD gene. These degenerate primers were designed using an alignment of bacterial accD genes obtained from public databases.