title: Mobilisation of bacteria in a fine-grained residual soil by electrophoresis.
abstract: An investigation of electrokinetic bacterial mobilisation in a residual soil from gneiss is presented here. The experimental program aimed at assessing the efficacy of electrophoresis against the electro-osmotic flow to transport endospores of Bacillus subtilis LBBMA 155 and nitrogen-starved cells of Pseudomonas sp. LBBMA 81. Electrokinesis was performed on a low hydraulic reconstituted clayey soil column submitted to a 5mA electrical current for 24h. Cells were coccoid-shaped and characterised as possessing low surface hydrophobicity and less than 1microm in diameter. Distribution coefficient for B. subtilis in the soil was between 16.8 and 19.9 times higher than that for Pseudomonas sp. Distribution coefficient for B. subtilis between eluate and anionic exchange column was 11.8 times higher than that for Pseudomonas sp. After the electrokinesis, it was shown that cells and endospores were distributed hyperbolically through the soil probe and moved against the electro-osmotic flow; however, endospores were transported throughout all soil core and starved cells only till half of its length. The higher transport efficiency of B. subtilis endospores was attributed to their higher negative charge on cell surface. These results demonstrate that electrokinesis can be used for bacteria transport in soils with low hydraulic conductivity, even against the electro-osmotic flow.
authors.affiliation: Universidade Federal de Viçosa, Laboratório de Biotecnologia e Biodiversidade para o Meio Ambiente, Departamento de Microbiologia, Centro de Ciências Biológicas e da Saúde, Av. P.H. Rolfs S/N, 36570-000 Viçosa, Minas Gerais, Brazil.
authors.forename: Ulisses Nunes
authors.initials: UN
authors.lastname: Da Rocha
authors.forename: Marcos Rogério
authors.initials: MR
authors.lastname: Tótola
authors.forename: Denise Maria Mano
authors.initials: DM
authors.lastname: Pessoa
authors.forename: José Tavares Araruna
authors.initials: JT
authors.lastname: Júnior
authors.forename: Júlio César Lima
authors.initials: JC
authors.lastname: Neves
authors.forename: Arnaldo Chaer
authors.initials: AC
authors.lastname: Borges
mesh_terms: D001419:Bacteria; D004563:Electrochemistry; D004586:Electrophoresis / Q000295:instrumentation* / Q000379:methods*; D007700:Kinetics; D009038:Motion; D010578:Petroleum / Q000382:microbiology; D012988:Soil Microbiology
chemical_list: D010578:Petroleum