Rodríguez-Martínez, Enid M.

Profile Picture

Filters

20061
Reset filters

Settings

Citations

Publication Search Results

Now showing 1 - 1 of 1
  • Thumbnail Image
    Publication
    Microbial diversity of a fluidized-bed bioreactor treating diesel-contaminated groundwater (Vega Baja, Puerto Rico)
    (2006) Rodríguez-Martínez, Enid M.; Massol-Deyá, Arturo A.; College of Arts and Sciences - Sciences; Montalvo-Rodríguez, Rafael R.; Ayala-del-Río, Héctor; Schadt, Christopher W.; Department of Biology; Pérez, Ana
    Culture and culture-independent techniques were used to characterize the microbial community structure within a fluidized bed reactor (FBR) used to remediate a dieselcontaminated aquifer. Under normal operating conditions, greater than 98% of total hydrocarbons were constantly removed. Over 25 different cultures were isolated, 92% utilized diesel constituents as carbon source and 20% were denitrifiers. Analysis of 16S rDNA demonstrated ample diversity with most cultures related to the Proteobacteria group. In order to better understand the dominant community structure, 16S rDNA clone libraries, Terminal Restriction Fragment Length Polymorphism (T-RFLP), and Functional Gene Microarrays (FGA) were analyzed from total community DNA samples. Clone libraries revealed at 61-days that the community was composed of 75% ßproteobacteria, 17% γ-proteobacteria and 8% α-proteobacteria while at 212-days was dominated by 77% γ-proteobacteria and 23% of ß-proteobacteria members. T-RFLP and FGA analysis revealed a core community structure with successional changes leading toward higher levels of richness and diversity as indicated by Shannon, Jaccard, and Schao statistical indexes. A total of 270 genes for organic contaminant degradation (including naphthalene, toluene [aerobic and anaerobic], octane, biphenyl, pyrene, xylene, phenanthrene, and benzene); and 333 genes involved in metabolic activities (nitrite and nitrous oxide reductases [nirS, nirK, and nosZ], dissimilatory sulfite reductases [dsrAB], potential metal reducing C-type cytochromes, and methane monooxygenase [pmoA]) were constantly detected. Genes for the degradation of MTBE, explosives, and chlorinated compounds were also present, indicating the broad catabolic potential of the microbial community present in the FBR unit.