Abstract
Here we report the oil degradation
genetic potential of six oil-degrading bacteria (ODB), previously used
as a bioremediation consortium, isolated from the hydrocoral Millepora
alcicornis and seawater. The strains were identified as Halomonas sp.
(LC_1), Cobetia sp. (LC_6), Pseudoalteromonas shioyasakiensis (LC_2),
Halopseudomonas aestusnigri (LC_3), Shewanella algae (LC_4), and
Brucella intermedia (LC_5). The taxonomic identification differed from
that of the original paper when we used whole genome gene markers
instead of just 16S rRNA gene. Genes responsible for the degradation of
aromatic hydrocarbons and n-alkanes were found in all genomes, although
different (and complementary) steps of the metabolic pathways were
unique to each strain. Genes for naphthalene and toluene degradation
were found in various strains. We annotated quinate degradation genes in
LC_6, while LC_3 and LC_5 presented genes for biosurfactant and
rhamnolipid biosynthesis. We also annotated genes related to beneficial
mechanisms for corals, such as genes involved in nitrogen and DMSP
metabolism, cobalamin biosynthesis and antimicrobial compounds
production. Our findings reinforce the importance of using bacterial
consortia for bioremediation approaches instead of single strains, due
to their complementary genomic arsenals. We also propose a genome-based
framework to select complementary ODB that can provide additional
benefits to coral health.
Keywords
PAH
Oil-degrading bacteria
Genome-based framework
Coral reefs
Bacteria