Conversion of Uric Acid into Ammonium in Oil-Degrading Marine Microbial Communities: a Possible Role of Halomonads

Degradation Network Reconstruction in Uric Acid and Ammonium Amendments in Oil-Degrading Marine Microcosms Guided by Metagenomic Data

“…The starting point of this study were the meta-sequences previously obtained by direct sequencing from two microcosm sets created using sediment samples from the harbor of Ancona (Italy; 43°37′N, 13°30′15″E), as described previously ( Gertler et al, 2015 ). Both microcosm setups were identical in size, composition, incubation, sampling regime and nutrient concentration with exception of the type of nitrogen source applied.…”

“…Furthermore, sediments in Ancona harbor are heavily contaminated due to its role as a major ferry terminal and industrial port on the Adriatic Sea. We hypothesize that the microbial community shifts previously observed after addition of UA and AMM ( Gertler et al, 2015 ) may have an influence in the selection of certain catabolic pathways. Potential protein-coding genes (≥20 amino acids long) obtained by direct Illumina HiSeq sequencing of DNA material of the corresponding microcosms ( Gertler et al, 2015 ) constituted the input information in our study.…”

“…However, AMM has been proved ineffective in treatment of real oil spill due to co-precipitation with phosphates in seawater. In a recent study, we have shown that biodegradable natural fertilizers like UA can be used as cost-efficient biostimulant for enhancing bacterial growth in polluted sediments ( Gertler et al, 2015 ). Each nitrogen source has its advantages and disadvantages, yet overall results have shown that the microbial populations were initially different from those found in the absence of biostimulants and that the degradation efficiency generally increased.…”

“…We found key catabolic variations associated to changes in community structure and environmental constraints ( Bargiela et al, 2015 ). In this work, this approach was applied to draft the catabolic networks of two different enrichment microcosms set up with sediments from chronically crude oil-contaminated marine sediments from Ancona harbor (Italy) and the natural fertilizer UA or AMM as nitrogen sources ( Gertler et al, 2015 ). Ancona harbor is very close to the urban area and hosts a multi-purpose port receiving cruise liners, passenger ferries, commercial liners and fishing boats.…”

Hydrocarbon pollutants shape bacterial community assembly of harbor sediments

“…The lack of nitrogen and phosphorus in marine environments is one of the main factors negatively affecting the growth of HC-degrading bacteria in polluted sites. Recently, the use of uric acid as a natural fertilizer for the bioremediation of marine oil pollution has been proposed to overcome this limitation (Ron and Rosenberg, 2014) and a microcosm-scale study showed its rapid conversion to ammonium and a role in the selection of microbial communities encompassing known hydrocarbonoclastic bacteria (Bargiela et al, 2015b;Gertler et al, 2015). Four of the tested isolates (one A. borkumensis and three M. hydrocarbonoclasticus) were capable to degrade uric acid suggesting their potential to be responsive to uric acid amendment in bioremediation trials.…”