Open AccessBoth Cycloclasticus spp. and Pseudomonas spp. as PAH‐degrading bacteria in the Seine estuary (France)
Author(s) -
Niepceron Maïté,
PortetKoltalo Florence,
Merlin Chloé,
MotelayMassei Anne,
Barray Sylvie,
Bodilis Josselin
Publication year - 2010
Publication title -
fems microbiology ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.377
H-Index - 155
eISSN - 1574-6941
pISSN - 0168-6496
DOI - 10.1111/j.1574-6941.2009.00788.x
Subject(s) - phenanthrene , microcosm , polycyclic aromatic hydrocarbon , naphthalene , environmental chemistry , pseudomonas , temperature gradient gel electrophoresis , biology , bioremediation , estuary , biodegradation , seawater , pyrene , microbiology and biotechnology , bacteria , 16s ribosomal rna , ecology , contamination , chemistry , organic chemistry , astrobiology , genetics
Like other highly urbanized and industrialized estuaries, the Seine estuary (France) has, for decades, received high inputs of polycyclic aromatic hydrocarbons (PAHs). In order to estimate the bioremediation potentials and to identify the bacterial species involved in hydrocarbon degradation, we used microcosms containing seawater from the Seine estuary supplemented with either naphthalene, phenanthrene, fluorene or pyrene. In the microcosms enriched with naphthalene or phenanthrene, hydrocarbon biodegradation was significant within 9 weeks (43% or 46%, respectively), as shown by analyses in GC‐MS. In similar microcosms incubated also with naphthalene or phenanthrene, analysis of the 16S rRNA gene sequences (DNA and cDNA) with denaturing gradient gel electrophoresis and clone libraries indicated that the PAH‐degrading communities were dominated by Cycloclasticus spp., confirming their universal key role in degradation of low‐molecular‐weight PAHs in marine environments. However, in contrast to previous studies, we found that Pseudomonas spp. also degraded naphthalene and phenanthrene in seawater; this occurred only after 21 days, as was confirmed by real‐time PCR. Although this genus has been abundantly described in the literature as a good PAH‐degrading bacterial group in soil or in sediment, to our knowledge, this is the first evidence of a significant fitness in PAH degradation in seawater.