Analysis of marine microbial communities colonizing various metallic materials and rust layers

Abstract

High-throughput sequencing was used to visualize microbial biocoenoses on different metallic surfaces and rust layers of highly corroded steels after immersion in coastal marine water for 30 months at Sanya, China. Distinct microbial community compositions were observed on these metallic surfaces. The dominant genus was the copper-tolerant, acid-producing Lactobacillus on copper alloys, the common aerobic surface colonizers Bacillus and Ruegeria on aluminum alloys, and aerobic biofilm-forming Pseudomonas on carbon steel. Most of these are copiotrophic microbes compared to planktonic microbes, which are oligotrophic. Additionally, sulfate-reducing prokaryotes (SRP) were detected in the rust layer, but the dominant genera changed from the outer layer to the inner part. The dominant genera detected in the outer, middle and inner rusts layers were Desulfotomaculum, Desulfonatronum (obligate anaerobe) and Desulfovibiro (electroactive), respectively. Further, the coexistence of methanogens with SRP suggests interspecies interactions.

Keywords:

• Microbial communities
• biofilm
• biocorrosion
• metal alloy
• rust layer
• seawater

Acknowledgements

This work was supported by the National Natural Science Foundation of China under Grant No.41576080, the Key Research and Development Plan of Shandong Province under Grant No. 2018GHY115003, the Strategic Leading Science & Technology Programme of the Chinese Academy of Sciences under Grant No. XDA13040403 and the National Program on Key Basic Research Project (973 Program) under Grant No. 2014CB643304.

Disclosure statement

The authors declare that they have no conflicts of interest.