Details

Autor(en) / Beteiligte

• Mariano, Caylla
• Mello, Ivani Souza
• Barros, Breno Martins
• da Silva, Gilvan Ferreira
• Terezo, Ailton Jose
• Soares, Marcos Antônio

Titel

Mercury alters the rhizobacterial community in Brazilian wetlands and it can be bioremediated by the plant-bacteria association

Ist Teil von

• Environmental science and pollution research international, 2020-04, Vol.27 (12), p.13550-13564

Ort / Verlag

Berlin/Heidelberg: Springer Berlin Heidelberg

Erscheinungsjahr

2020

Quelle

MEDLINE

Beschreibungen/Notizen

• This study examined how soil mercury contamination affected the structure and functionality of rhizobacteria communities from Aeschynomene fluminensis and Polygonum acuminatum and how rhizobacteria mediate metal bioremediation. The strains were isolated using culture-dependent methods, identified through 16S rDNA gene sequencing, and characterized with respect to their functional traits related to plant growth promotion and resistance to metals and antibiotics. The bioremediation capacity of the rhizobacteria was determined in greenhouse using corn plants. The isolated bacteria belonged to the phyla Actinobacteria, Deinococcus-Thermus, Firmicutes, and Proteobacteria, with great abundance of the species Microbacterium trichothecenolyticum. The rhizobacteria abundance, richness, and diversity were greater in mercury-contaminated soils. Bacteria isolated from contaminated environments had higher minimum inhibitory concentration values, presented plasmids and the merA gene, and were multi-resistant to metals and antibiotics. Enterobacter sp. _ C35 and M . trichothecenolyticum_ C34 significantly improved (Dunnett’s test, p  < 0.05) corn plant growth in mercury-contaminated soil. These bacteria helped to reduce up to 87% of the mercury content in the soil, and increased the mercury bioaccumulation factor by up to 94%. Mercury bioremediation mitigated toxicity of the contaminated substrate. Enterobacter sp._C35, Bacillus megaterium _C28, and Bacillus mycoides _C1 stimulated corn plant growth and could be added to biofertilizers produced in research and related industries.