Proteome of Gluconacetobacter diazotrophicus co-cultivated with sugarcane plantlets.
Gluconacetobacter diazotrophicus is a micro-aerobic bacterium able to fix atmospheric nitrogen in endophytic mode. A proteomic approach was used to analyze proteins differentially expressed in the presence and absence of sugarcane plantlets. Two-dimensional gel electrophoresis (2-DE) showed 42 spots with altered levels of expression. Analysis of these spots by matrix-assisted laser desorption ionization time-of-flight in tandem (MALDI-TOF-TOF) identified 38 proteins. Differentially expressed proteins were associated with carbohydrate and energy metabolism, folding, sorting and degradation processes, and transcription and translation. Among proteins expressed in co-cultivated bacteria, four belong to membrane systems; others, like a transcription elongation factor (GreA), a 60 kDa chaperonin (GroEL), and an outer membrane lipoprotein (Omp16) have also been described in other plant-bacteria associations, indicating a common protein expression pattern as a result of symbiosis. A high protein content of 60kDa chaperonin isoforms was detected as non-differentially expressed proteins of the bacteria proteome. These results allow the assessment of the physiological significance of specific proteins to G. diazotrophicus metabolism and to the pathways involved in bacteria-host endophytic interaction.
dos Santos
Marise Fonseca
MF
Federal University of Paraná, Campus Palotina, Brazil.
Muniz de Pádua
Vânia Lúcia
VL
de Matos Nogueira
Eduardo
E
Hemerly
Adriana Silva
AS
Domont
Gilberto Barbosa
GB
D001426:Bacterial Proteins / Q000032:analysis*; D050260:Carbohydrate Metabolism / Q000235:genetics; D018920:Coculture Techniques; D004734:Energy Metabolism / Q000235:genetics; D041821:Gluconacetobacter / Q000235:genetics* / Q000378:metabolism; D054884:Host-Pathogen Interactions / Q000235:genetics*; D020543:Proteome / Q000032:analysis*; D031786:Saccharum / Q000382:microbiology*; D013559:Symbiosis / Q000235:genetics
D001426:Bacterial Proteins; D020543:Proteome