Fig. 4: Sequence analysis.

a Flower figure and b Venn diagram. OY-RU, the rust layer or biofilm at the oyster/steel interface; AS-RU, the rust layer or biofilm at the ascidian/steel interface; SW-RU, the rust layer or biofilm at the steel interface which not covered by macrofouling; OYS, the biofilm in oyster’s secretion; OYT, the biofilm in oyster’s tissue.