IBBM   21076
INSTITUTO DE BIOTECNOLOGIA Y BIOLOGIA MOLECULAR
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
BORDETELLA BRONCHISEPTICA LAPD INTERACTS WITH TWO DIFFERENT DIGUANYLATE CYCLASES
Autor/es:
SISTI F; AMBROSIS N; FERNANDEZ J
Lugar:
Buenos Aires
Reunión:
Congreso; Reunión Conjunta de Sociedades de Biociencia 2017; 2017
Institución organizadora:
SAIB (Sociedad Argentina de Investigaciones Bioquímicas)
Resumen:
Cyclic-di-GMP (cdG) is a widely distributed second messenger inthe bacterial world. It is produced by diguanylate cyclases (DGCs)and can direct many cellular processes like motility and biofilm formation.Over the last years our group has been working on phenotypesregulated by this molecule in the genus Bordetella. Wehave previously described that cdG regulates biofilm formation inB. bronchiseptica. This process relies, at least in part, on an effectorsystem homologue to the Pseudomonas fluorescens Lap system:LapD, LapG and BrtA.We speculate that there might be at least one DGC that physicallyinteract with LapD in order to provide cdG in a specific manner to thementioned Lap system. Using a bioinformatic methodology we havelooked into every B. bronchiseptica membrane DGC and predictedthat BdcG, a putative DGC, physically interacts with LapD. We havealso considered that BdcA could interact with LapD because our previousresults showed a strong correlation between BdcA activity andbiofilm formation.In order to advance on the knowledge of the recently found BdcG,we analyze DGC activity using two different methodologies (heterologousexpression on a P. fluorescens reporter strain and cdG directmeasurement). Neither of the approaches could confirm if BdcG isan active DGC.Bacterial Two Hybrid experiments were used to figure out if mentionedDGCs interact with LapD. Statistically significant differencesbetween LapD-BdcA, LapD-BdcG and controls were found in β-galactosidaseassays. Those results indicate that LapD physically interactswith BdcA and BdcG.Furthermore we have also generated simple and double knock-outmutants of bdcA and bdcG. We hypothesized that deletion of DGCsmay impaired biofilm formation. Neither simple nor double mutantsshowed a biofilm formation defect.Taking in mind that B. bronchiseptica genome has 10 sequencesthat encode for DGCs our results suggest that other DGCs are partof the regulation network through Lap proteins.