Colonization characteristics of pioneer surface-associated eukaryotes during natural biofilm formation on PDMS-based composites via 18S rRNA gene sequencing methods

Abstract

Marine biofilms formed on submerged substrates are important sources of biofouling. Despite extensive studies dedicated to the surface-biofilm bacteria, few studies focused exclusively on the colonization characteristics of pioneer surface-associated eukaryotes (PSE) in biofilms on composite surfaces. Given this, the colonization dynamics of the biofilm-forming PSE on different carbon nanotubes (CNTs)-filled polydimethylsiloxane (PDMS) composites were investigated via 18S rRNA gene sequencing. Diverse PSE with differential taxonomic compositions, structures and diversity characteristics were colonized on different CNTs/PDMS composites, and their colonization was greatly influenced after CNTs incorporation in PDMS. Bacillariophyta, Annelida and Arthropoda were the core phyla, taking 44.17% of the total; Aphelochaeta, Navicula and Pseudovorticella were the dominant genera, taking 38% of the total. These dominant taxa showed different sensitivities to the CNT incorporation. Some dominant PSE involved multiple biosynthesis and degradation pathways (e.g. Nucleoside and Nucleotide Biosynthesis, Amino Acid Biosynthesis and Fatty Acid and Lipid Degradation), and two key functional modules (Module 50 and Module 88) related to the initial colonization of Navicula were excavated via the correlation network analysis. Our study revealed the potential mechanisms on how different CNTs/PDMS composites influenced the colonization dynamics of PSE and provided fundamental guidance for future development of the anti-biofouling materials.