02470naa a2200217 a 450000100080000000500110000800800410001902400350006010000190009524501460011426000090026052017690026965000270203865300100206565300330207565300250210865300270213370000170216070000150217777300600219214915412018-05-24       2008    bl uuuu     u00u1 u    #d7 a10.1007/s12275-007-0245-x2DOI1 aMOTA, F. F. da  aAuxin production and detection of the gene coding for the auxin effux carrier (AEC) protein in Paenibacillus polymyxa.h[electronic resource]  c2008  aDifferent species of Paenibacillus are considered to be plant growth-promoting rhizobacteria (pGPR) due to their ability to repress soil borne pathogens, fix atmospheric nitrogen, induce plant resistance to diseases and/for produce plant growth-regulating substances such as auxins. Although it is known that indole-3-acetic acid (lAA) is the primary naturally occurring auxin excreted by Paenibacülus species, its transport mechanisms (auxin effiux carriers) have not yet been characterized. In this study, the auxin production of P. polymyxa and P. graminis, which are prevalent in the rhizospheres of maize and sorghum sown in Brazil, was evaluated. In addition, the gene encoding the Auxin Effiux Carrier (AEC) protein from P. polymyxa DSM36T was sequenced and used to determine if various strains of P. polymyxa and P. graminis possessed this gene. Each of the 68 P. polymyxa strains evaluated in this study was able to produce IAA, which was produced at concentrations varyjng from 1 to 17 ug/ml. However, auxin production was not detected in any of the 13 P. graminis strains tested in this study. Dift'erent primers were designed for the PCR amplification of the gene coding for the AEC in P. polymyxa, and the predicted protein of 319 aa was homologous to AEC from Bacillus amyloliquefaciens, B. licheniformis, and B. subtilis. However, no product was observed when these primers were used to amplify the genomic DNA of seven strains of P. graminis, which suggests that this gene is not present in this species. Moreover, none of the P. graminis genomes tested were homol-ogous to the gene coding for AEC, whereas ali of the P. polymyxa genomes evaluated were. This is the first study to demonstrate that the AEC protein is present in P. polymyxa genome.  aPaenibacillus polymyxa  aAuxin  aAuxin efflux earrier protein  aIndole-3-aeetic acid  aPaenibacillus graminis1 aGOMES, E. A.1 aSELDIN, L.  tJournal of Microbiologygv. 46, n. 3, p. 257-264, 2008.