Changing bacterial profile of Sundarbans, the world heritage mangrove: Impact of anthropogenic interventions

Abstract

Mangrove microbial communities and their associated activities have profound impact on biogeochemical cycles. Although microbial composition and structure are known to be influenced by biotic and abiotic factors in the mangrove sediments, finding direct correlations between them remains a challenge. In this study we have explored sediment bacterial diversity of the Sundarbans, a world heritage site using a culture-independent molecular approach. Bacterial diversity was analyzed from three different locations with a history of exposure to differential anthropogenic activities. 16S rRNA gene libraries were constructed and partial sequencing of the clones was performed to identify the microbial strains. We identified bacterial strains known to be involved in a variety of biodegradation/biotransformation processes including hydrocarbon degradation, and heavy metal resistance. Canonical Correspondence Analysis of the environmental and exploratory datasets revealed correlations between the ecological indices associated with pollutant levels and bacterial diversity across the sites. Our results indicate that sites with similar exposure of anthropogenic intervention reflect similar patterns of microbial diversity besides spatial commonalities.

Bioinformatic Approaches Including Predictive Metagenomic Profiling Reveal Characteristics of Bacterial Response to Petroleum Hydrocarbon Contamination in Diverse Environments

“…Pathogenic microorganisms are known to be important degraders of petroleum hydrocarbons. Several strains of infectious microbes such as Burkholderia 32 , Stenotrophomonas 33, 34 and Mycobacterium 35 have been shown to harbor impressive capabilities for degradation of a variety of petroleum hydrocarbons. In the present study, pathogens such as Mycobacterium and Burkholderia , were identified as genus level biomarkers for C samples and Tb samples respectively.…”

“…In the M samples, two component systems for starvation of phosphate (M00434), a limiting nutrient for mangroves 34 and metal tolerance (M00499) were detected as differentially abundant (Fig. 3, Supplementary Fig.…”

Diverse Profiles of AI-1 Type Quorum Sensing Molecules in Cultivable Bacteria from the Mangrove (Kandelia obovata) Rhizosphere Environment

“…Biogeography (distinct soil depths and locations) may be a major determinant factor that influences bacterial structure. In addition, anthropogenic interference may contribute to this difference, because various degrees of human activities (urbanization, pollution, and aquaculture) have different effects on environmental competitiveness and co-shaping the microbial communities (Marcial et al, 2008; Basak et al, 2015; Chakraborty et al, 2015). …”

Metagenomic Characteristics of Bacterial Response to Petroleum Hydrocarbon Contamination in Diverse Environments as Revealed by Functional Taxonomic Strategies

“…S2, Supplementary Table S3). In the M samples, two component systems for starvation of phosphate (M00434), a limiting nutrient for mangroves 59 and metal tolerance (M00499) were detected as differentially abundant (Fig. 5, Supplementary Fig.…”