Expression of alkane monooxygenase (alkB) genes by plant-associated bacteria in the rhizosphere and endosphere of Italian ryegrass (Lolium multiflorum L.) grown in diesel contaminated soil.
For phytoremediation of organic contaminants, plants have to host an efficiently degrading microflora. To assess the role of endophytes in alkane degradation, Italian ryegrass was grown in sterile soil with 0, 1 or 2% diesel and inoculated either with an alkane degrading bacterial strain originally derived from the rhizosphere of Italian ryegrass or with an endophyte. We studied plant colonization of these strains as well as the abundance and expression of alkane monooxygenase (alkB) genes in the rhizosphere, shoot and root interior. Results showed that the endophyte strain better colonized the plant, particularly the plant interior, and also showed higher expression of alkB genes suggesting a more efficient degradation of the pollutant. Furthermore, plants inoculated with the endophyte were better able to grow in the presence of diesel. The rhizosphere strain colonized primarily the rhizosphere and showed low alkB gene expression in the plant interior.
AIT Austrian Institute of Technology GmbH, Bioresources Unit, A-2444 Seibersdorf, Austria.
Verania
V
Andria
Thomas G
TG
Reichenauer
Angela
A
Sessitsch
D001419:Bacteria / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001673:Biodegradation, Environmental; D042926:Cytochrome P-450 CYP4A / Q000235:genetics* / Q000378:metabolism; D060026:Endophytes / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D005742:Gasoline / Q000032:analysis; D015964:Gene Expression Regulation, Bacterial; D015971:Gene Expression Regulation, Enzymologic; D008129:Lolium / Q000254:growth & development / Q000382:microbiology*; D058441:Rhizosphere; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism*
D001426:Bacterial Proteins; D005742:Gasoline; D012989:Soil Pollutants; D042926:Cytochrome P-450 CYP4A