Differential proteomic response to phosphorus deficiency and aluminum stress of the Al-tolerant phosphobacteria strain Enterobacter sp. RJAL6 isolated from acidic soils.

ABSTRACT: Aluminum (Al)–tolerant phosphobacteria can improve plant performance in acidic soils by increasing Al complexing and phosphorus (P) availability. However, it is almost unknown how Al stress along with P deficiency affect the bacterial biochemistry and physiology. Because high Al levels and low P availability often occur simultaneously in acidic soils, we have evaluated the single and mutual effects of a high Al stress and P deficiency on the proteome of the Al‒tolerant phosphobacteria strain Enterobacter sp. RJAL6. This strain was previously isolated from the rhizosphere of Lollium perenne plants grown in acidic soil. The strain was cultivated in mineral media modified to contain i) high P (1.4 mM) in the absence of Al, ii) high P (1.4 mM) and high Al (10 mM), iii) low P (0.05 mM) in the absence of Al, and iv) low P (0.05 mM) and high Al (10 mM). Total proteins from bacterial cells were extracted at the end of the exponential phase of growth and subjected to high–throughput proteomics analysis. The results showed that P deficiency was mainly associated with an upregulation of the P metabolism proteins subject to Pho regulon control, including phosphatases and transporters involved in the uptake of organophosphorus compounds such as phosphomonoesters, phosphonates and glycerol–3–phosphate. Aluminum exposure primarily decreased the expression of iron (Fe)–sulfur and haem-containing proteins with a concomitant upregulation of Fe acquisition and metabolism proteins, including siderophore precursors and receptors of Fe–chelator complexes. Here, we demonstrated the preponderant role that Al plays in the adjustment of Fe homeostasis, and consequently in the central metabolism of the bacteria. This is the first report of a proteomic study of the interaction between high Al and P deficiency in acidic soil–adapted bacteria. This knowledge is crucial for developing bioinoculants for crops affected by both Al toxicity and P deficiency.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Enterobacter Sp. Rjal6

SUBMITTER: Stephane Claverol  

LAB HEAD: Stephane Claverol

PROVIDER: PXD041868 | Pride | 2023-09-27

REPOSITORIES: Pride