title: Screening beneficial rhizobacteria from Spartina maritima for phytoremediation of metal polluted salt marshes: comparison of gram-positive and gram-negative strains.
abstract: The aim of our work was the isolation and characterization of bacteria from the rhizosphere of Spartina maritima in the metal contaminated Odiel estuary (Huelva, SW Spain). From 25 strains, 84 % were identified as gram-positive, particularly Staphylococcus and Bacillus. Gram-negative bacteria were represented by Pantoea and Salmonella. Salt and heavy metal tolerance, metal bioabsorption, plant growth promoting (PGP) properties, and biofilm formation were investigated in the bacterial collection. Despite the higher abundance of gram-positive bacteria, gram-negative isolates displayed higher tolerance toward metal(loid)s (As, Cu, Zn, and Pb) and greater metal biosorption, as deduced from ICP-OES and SEM-EDX analyses. Besides, they exhibited better PGP properties, which were retained in the presence of metals and the ability to form biofilms. Gram-negative strains Pantoea agglomerans RSO6 and RSO7, together with gram-positive Bacillus aryabhattai RSO25, were selected for a bacterial consortium aimed to inoculate S. maritima plants in metal polluted estuaries for phytoremediation purposes.
authors.affiliation: Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad de Sevilla, c/Profesor García González, 2, 41012, Sevilla, Spain.
authors.forename: Karina I
authors.initials: KI
authors.lastname: Paredes-Páliz
authors.affiliation: Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad de Sevilla, c/Profesor García González, 2, 41012, Sevilla, Spain.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Caviedes
authors.affiliation: Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad de Sevilla, c/Profesor García González, 2, 41012, Sevilla, Spain.
authors.forename: Bouchra
authors.initials: B
authors.lastname: Doukkali
authors.affiliation: Departamento de Biología Vegetal y Ecología, Facultad de Biología, Universidad de Sevilla, c/Profesor García González, 4, 41012, Sevilla, Spain.
authors.forename: Enrique
authors.initials: E
authors.lastname: Mateos-Naranjo
authors.affiliation: Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad de Sevilla, c/Profesor García González, 2, 41012, Sevilla, Spain.
authors.forename: Ignacio D
authors.initials: ID
authors.lastname: Rodríguez-Llorente
authors.affiliation: Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad de Sevilla, c/Profesor García González, 2, 41012, Sevilla, Spain. epajuelo@us.es.
authors.forename: Eloísa
authors.identifier: http://orcid.org/0000-0002-1084-5301
authors.initials: E
authors.lastname: Pajuelo
mesh_terms: D001151:Arsenic / Q000378:metabolism*; D001673:Biodegradation, Environmental; D063366:Estuaries; D006090:Gram-Negative Bacteria / Q000378:metabolism*; D006094:Gram-Positive Bacteria / Q000378:metabolism*; D019216:Metals, Heavy / Q000378:metabolism*; D006109:Poaceae / Q000254:growth & development / Q000382:microbiology*; D058441:Rhizosphere; D054712:Salinity; D013030:Spain; D053833:Wetlands
chemical_list: D019216:Metals, Heavy; D001151:Arsenic
keywords: Biofilms; Estuaries; Heavy metals; Metal biosorption; Odiel River; Phytoremediation; Plant growth promoting rhizobacteria (PGPR); Spartina maritima