Mugge Rachel L, Moseley Rachel D, Hamdan Leila J
U.S. Naval Research Laboratory, Ocean Sciences Division, Stennis Space Center, MS 39529, USA.
School of Ocean Science and Engineering, University of Southern Mississippi, Ocean Springs, MS 39564, USA.
Microorganisms. 2023 Sep 27;11(10):2416. doi: 10.3390/microorganisms11102416.
The number of built structures on the seabed, such as shipwrecks, energy platforms, and pipelines, is increasing in coastal and offshore regions. These structures, typically composed of steel or wood, are substrates for microbial attachment and biofilm formation. The success of biofilm growth depends on substrate characteristics and local environmental conditions, though it is unclear which feature is dominant in shaping biofilm microbiomes. The goal of this study was to understand the substrate- and site-specific impacts of built structures on short-term biofilm composition and functional potential. Seafloor experiments were conducted wherein steel and wood surfaces were deployed for four months at distances extending up to 115 m away from three historic (>50 years old) shipwrecks in the Gulf of Mexico. DNA from biofilms on the steel and wood was extracted, and metagenomes were sequenced on an Illumina NextSeq. A bioinformatics analysis revealed that the taxonomic composition was significantly different between substrates and sites, with substrate being the primary determining factor. Regardless of site, the steel biofilms had a higher abundance of genes related to biofilm formation, and sulfur, iron, and nitrogen cycling, while the wood biofilms showed a higher abundance of manganese cycling and methanol oxidation genes. This study demonstrates how substrate composition shapes biofilm microbiomes and suggests that marine biofilms may contribute to nutrient cycling at depth. Analyzing the marine biofilm microbiome provides insight into the ecological impact of anthropogenic structures on the seabed.
在沿海和近海区域，海底人造建筑的数量不断增加，如沉船、能源平台和管道等。这些建筑通常由钢铁或木材构成，是微生物附着和生物膜形成的基质。生物膜生长的成功与否取决于基质特性和当地环境条件，不过目前尚不清楚在塑造生物膜微生物群落方面哪种特性起主导作用。本研究的目的是了解人造建筑对短期生物膜组成和功能潜力的基质及位点特异性影响。开展了海底实验，将钢铁和木材表面放置在距离墨西哥湾三艘历史悠久（超过50年）的沉船最远115米处达四个月之久。提取了钢铁和木材上生物膜的DNA，并在Illumina NextSeq上对宏基因组进行测序。生物信息学分析表明，基质和位点之间的分类组成存在显著差异，其中基质是主要决定因素。无论位点如何，钢铁生物膜中与生物膜形成、硫、铁和氮循环相关的基因丰度较高，而木材生物膜中锰循环和甲醇氧化基因的丰度较高。本研究证明了基质组成如何塑造生物膜微生物群落，并表明海洋生物膜可能有助于深海的营养物质循环。分析海洋生物膜微生物群落有助于深入了解人为建筑对海底的生态影响。
