The metagenomic landscape of xenobiotics biodegradation in mangrove sediments

Author(s)

Cabral, Lucelia ^{[1, 2]} ; Noronha, Melline Fontes ^{[1, 2]} ; Pereira de Sousa, Sanderson Tarciso ^{[1, 2]} ; Lacerda-Junior, Gileno Vieira ^{[1, 2]} ; Richter, Larissa ^[3] ; Fostier, Anne Helene ^[3] ; Andreote, Fernando Dini ^[4] ; Hess, Matthias ^[5] ; de Oliveira, Valeria Maia ^[1]

Affiliation

^[1] Univ Estadual Campinas, Ctr Chem Biol & Agr CPQBA, UNICAMP, Campinas, SP - Brazil

^[2] Univ Estadual Campinas, UNICAMP, IB, Campinas, SP - Brazil

^[3] Univ Estadual Campinas, UNICAMP, Inst Chem, Campinas, SP - Brazil

^[4] Univ Sao Paulo, Luiz de Queiroz Coll Agr, Dept Soil Sci, Piracicaba, SP - Brazil

^[5] Univ Calif Davis, Dept Anim Sci, Davis, CA 95616 - USA

• Document type: Journal article
• Source: ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY; v. 179, p. 232-240, SEP 15 2019.
• Web of Science Citations: 0

Abstract

Metagenomics is a powerful approach to study microorganisms present in any given environment and their potential to maintain and improve ecosystem health without the need of cultivating these microorganisms in the laboratory. In this study, we combined a cultivation-independent metagenomics approach with functional assays to identify the detoxification potential of microbial genes evaluating their potential to contribute to xenobiotics resistance in oil-impacted mangrove sediments. A metagenomic fosmid library containing 12,960 clones from highly contaminated mangrove sediment was used in this study. For assessment of metal resistance, clones were grown in culture medium with increasing concentrations of mercury. The analyses metagenomic library sequences revealed the presence of genes related to heavy metals and antibiotics resistance in the oil-impacted mangrove microbiome. The taxonomic profiling of these sequences suggests that at the genus level, Geobacter was the most abundant genus in our dataset. A functional screening assessment of the metagenomic library successfully detected 24 potential heavy metal tolerant clones, six of which were capable of growing with increased concentrations of mercury. The genetic characterization of selected clones allowed the detection of genes related to detoxification processes, such as chromate transport protein ChrA, haloacid dehalogenase-like hydrolase, lipopolysaccharide transport system, and 3-oxoacyl-{[}acyl-carrier-protein] reductase. Clones were capable of growing in medium containing increased concentrations of metals and antibiotics, but none manifested strong mercury removal from culture medium characteristic of mercuric reductase activity. These results suggest that resistance to xenobiotic stress varies greatly and that additional studies to elucidate the potential of metal biotransformation need to be carried out with the goal of improving bioremediation application. (AU)

• FAPESP's process: 13/20670-0 - Assessment of the functional diversity and bioprospection of genes involved in degradation of hydrocarbons and transformation of heavy metals in mangrove sediments
• Grantee: Lucélia Cabral
• Support type: Scholarships abroad - Research Internship - Post-doctor
• FAPESP's process: 12/16850-0 - Assessment of the functional diversity and bioprospection of genes involved in degradation of hydrocarbons and transformation of heavy metals in mangrove sediments
• Grantee: Lucélia Cabral
• Support type: Scholarships in Brazil - Post-Doctorate
• FAPESP's process: 12/06245-2 - Metatranscriptomics and genomic context of microbial genes related to biogeochemical cycles in mangroves
• Grantee: Fernando Dini Andreote
• Support type: Regular Research Grants