ROLE OF BACTERIAL PYRROLOQUINOLINE QUINONE IN PHOSPHATE SOLUBILIZING ABILITY AND IN PLANT GROWTH PROMOTION ON STRAIN SERRATIA SP. S119

LUDUEÑA, LILIANA; ANZUAY, MARÍA SOLEDAD; ANGELINI, JORGE; BARROS, GERMÁN; LUNA, MARÍA FLAVIA; MONGE, MARÍA DEL PILAR; FABRA, ADRIANA; TAURIAN, TANIA

SYMBIOSIS

SPRINGER

Lugar: Berlin; Año: 2017

0334-5114

The aim of this study was to analyze if cofactor pyrroquinoline quinone fromSerratia sp. S119 is involved in the inorganic phosphate solubilizationmechanism and in its ability to promote the plant growth. Site directedmutagenesis was performed to obtain a pqqE- minus mutant of strain Serratiasp. S119. The phosphate solubilization ability, gluconate and PQQ productionof the mutant Serratia sp. RSL (pqqE-) was analyzed. Mutant RSL (pqqE-)showed significant decrease in P soluble and gluconic acid levels produced andundetectable levels of PQQ cofactor compared with wild-type strain.Complementation with synthetic PQQ cofactor restored P solubilization andgluconate production reaching the levels produced by wild-type strain. PqqEgene sequence indicated that it is highly conserved within Serratia strains andits product shows conserved motifs found in other PqqE proteins of severalbacteria. The effect of the inoculation of the PQQ- mutant on peanut and maizeplants was evaluated in pot assays. Plants growth parameters showed nodifferences among the different treatments indicating that PQQ from Serratiasp. S119 is not involved in the growth promotion of these plants. PQQcofactor is essential for phosphate solubilization ability of Serratia sp. S119but is not required for growth promotion of peanut and maize plants.