Study on the Bacterial Communities of the Biofilms on Titanium, Aluminum, and Copper Alloys at 5,772 m Undersea in Yap Trench

• Published in: Frontiers in microbiology Vol. 13; p. 831984
• Main Authors: Zhai, Xiaofan, Cao, Wei, Zhang, Yimeng, Ju, Peng, Chen, Juna, Duan, Jizhou, Sun, Chengjun
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 18.03.2022
• Subjects: biofilm; hadal environment; metal alloys; microbial communities; Microbiology; Yap Trench; Yap Trench; hadal environment; microbial communities; metal alloys; biofilm
• ISSN: 1664-302X; 1664-302X
• DOI: 10.3389/fmicb.2022.831984

Biofilms formed on metal surfaces strongly affect metallic instruments serving in marine environments. However, due to sampling difficulty, less has been known about the bacterial communities of the biofilm on metallic surfaces in hadal environments, so the failure process of these deep-sea metallic instruments influenced by microbial communities could be hardly predicted. In this research, seven alloys, including titanium, aluminum, and copper alloys, were exposed in Yap Trench hadal environment for 1 year. Thus, the communities of the biofilms formed on metallic surfaces at 5,772 m undersea in Yap Trench were initially reported in previous studies. Then, 16S rRNA gene sequencing was performed to visualize the bacterial communities of the biofilms formed on titanium, aluminum, and copper alloys at 5,772 m undersea in Yap Trench. It was found that Proteobacteria was the dominant phylum in all samples, but distinct genera were discovered on various alloys. The titanium alloy provided a suitable substrate for a mutualistic symbiotic biofilm with abundant bacterial richness. Aluminum alloys without copper components showed the least bacterial richness and formed a cold-adapted and oligotrophic-adapted biofilm containing the genera and , while copper-present alloys showed relatively high bacterial richness with copper-resistant or even copper-utilizing biofilms constituting the genera , , and on the surfaces. Furthermore, among all the element components contained in alloys investigated in this research, copper element showed the strongest influences on the composition and function of microbial communities in the biofilms formed on various metallic surfaces.