Species sorting during biofilm assembly by artificial substrates deployed in a cold seep system

Abstract

Studies focusing on biofilm assembly in deep-sea environments are rarely conducted. To examine the effects of substrate type on microbial community assembly, biofilms were developed on different substrates for different durations at two locations in the Red Sea: in a brine pool and in nearby bottom water (NBW) adjacent to the Thuwal cold seep II. The composition of the microbial communities in 51 biofilms and water samples were revealed by classification of pyrosequenced 16S rRNA gene amplicons. Together with the microscopic characteristics of the biofilms, the results indicate a stronger selection effect by the substrates on the microbial assembly in the brine pool compared with the NBW. Moreover, the selection effect by substrate type was stronger in the early stages compared with the later stages of the biofilm development. These results are consistent with the hypotheses proposed in the framework of species sorting theory, which states that the power of species sorting during microbial community assembly is dictated by habitat conditions, duration and the structure of the source community. Therefore, the results of this study shed light on the control strategy underlying biofilm-associated marine fouling and provide supporting evidence for ecological theories important for understanding the formation of deep-sea biofilms.

Genomic and Transcriptomic Evidence for Carbohydrate Consumption among Microorganisms in a Cold Seep Brine Pool

“…Biofilms were developed on six different types of materials in the brine pool for 3 and 6 days. The devices for biofilm development has been reported in Zhang et al (2014) and the schematic diagrams are also shown in Figure S1 in the present study. The materials were deployed into the brine pool by the ROV.…”

“…This brine pool is located at a depth of approximately 850 m and is characterized by a high concentration of potential electron acceptors such as nitrate (18.5 mg L −1 ) and sulfate (2.7 g L −1 ). The particulate organic carbon (POC) concentration was 3.5 mg L −1 which was 10 times greater than that of the adjacent normal deep-sea water (NDW) (Zhang et al, 2014, 2015). In contrast, methane and hydrogen sulfide were depleted with respect to NDW.…”

“…Our previous investigation on the metagenomics of biofilms developed on artificial surfaces (Zhang et al, 2014, 2015) has illustrated the developmental processes of biofilms in a brine pool associated with the Thuwal cold seeps (Batang et al, 2012) on the floor of the Red Sea. This brine pool is located at a depth of approximately 850 m and is characterized by a high concentration of potential electron acceptors such as nitrate (18.5 mg L −1 ) and sulfate (2.7 g L −1 ).…”

Family-wide Structural Characterization and Genomic Comparisons Decode the Diversity-oriented Biosynthesis of Thalassospiramides by Marine Proteobacteria

“…To create the THP-1 conditioned medium, 4 l of a 2 mM fibrillar A␤ [25][26][27][28][29][30][31][32][33][34][35] (Tocris) suspension was added to 24-well plates and allowed to air-dry. THP-1 cells were subsequently plated on the A␤-coated wells at a density of 20,000/well in Neurobasal medium.…”

“…DNA Extraction, 16S rRNA Gene Amplification, and Sequencing-DNA extraction was performed as described previously (25). Briefly, the cultured bacterial cells were pelleted by centrifugation at 4000 ϫ g for 10 min and then lysed with lysozyme, proteinase K, and 10% SDS.…”