Microbial community response to a simulated hydrocarbon spill in mangrove sediments

Abstract

In this study, we examined the hypothesis that the microbial communities in mangrove sediments with different chemical and historical characteristics respond differently to the disturbance of a hydrocarbon spill. Two different mangrove sediments were sampled, one close to an oil refinery that had suffered a recent oil spill and another that had not been in contact with oil. Based on the sampled sediment, two sets of mesocosms were built, and oil was added to one of them. They were subjected to mimicked mangrove conditions and monitored for 75 days. Archaeal and bacterial communities were evaluated through PCR-DGGE. Both communities showed the emergence of small numbers of novel bands in response to oil pollution. 16S rRNA gene clone libraries were constructed from both mesocosms before the addition of oil and at day 75 after oil addition. LIBSHUFF analysis showed that both mangrove-based mesocosms contained similar communities at the start of the experiment and that they were different from the initial one, as well as from each other, after 75 days. These results hint at a role of environmental history that is not obvious from community diversity indicators, but is apparent from the response to the applied stress.

Diversity and identification of methanogenic archaea and sulphate-reducing bacteria in sediments from a pristine tropical mangrove

“…Both groups of organisms have been observed in previous studies based on 16S rRNA gene clone libraries (Yan et al 2006;Liang et al 2007;Lyimo et al 2009;Taketani et al 2010); however, the diversity of genes related to methanogenesis and sulphate reduction remains unexplored in mangrove sediments. The use of so-called functional genes is often regarded as a powerful tool for the study groups of organisms associated with a given metabolic process.…”

Bioremediation of polycyclic aromatic hydrocarbons by Acinetobacter species isolated from ecological sources

“…Several researchers (MacNaughton et al, 1999;Barathi and Vasudevan 2001;Dubinsky et al, 2013;Mason et al, 2014) have revealed that microorganisms play a significant role in insitu biodegradation of hydrocarbons in environment and significance of indigenous oil-degrading bacteria. Bacteria breaks down contaminants by using them as energy source or co-metabolizing them with energy source (Taketani et al, 2010). Two species of bacteria consortium isolated from petrochemical soil and identified as Bacillus cereus and Bacillus vireti (Mohandass et al, 2012).…”

Diversidade de arquéias e bactérias envolvidas na ciclagem do nitrogênio em sedimentos de manguezais

“…These changes were further validated statistically by ordination analysis, which allowed the determination of the parameters influencing the structure of these communities. Among the parameters found (distinct mangrove characteristics, salinity, and oil contamination), some were already identified for bacterial changes in mangrove sediments, as oil contamination (Taketani et al 2010a) or the mangrove location . In addition to the variables included in the ordination analysis, other environmental parameters (not included in the ordination analysis due to absence of true replicates) were distinct in the studied areas, with the most different area located at Point 1 of the Prs Mgv.…”

“…Studies of microbial life in mangroves have assessed bacterial communities in well-preserved mangroves , urban mangroves , mangroves affected by shrimp farms (Sousa et al 2006) and contaminated with hydrocarbons (Taketani et al 2010a). However, most of these studies focused on bacterial communities, neglecting the diversity of archaea in such environments.…”