Figure 1.

Phylum-level composition of the biofilms in the signal molecules treatment experiment. Biofilms that had been growing for 9 days in the subtidal zone of Hong Kong waters were collected and subjected to different signal molecules treatments in the laboratory. Then, the genomic DNA of each biofilm sample was sequenced for metagenomic analysis. The biofilms treated with seawater were labeled as “control,” and the untreated biofilm was labeled as “initial.” Except for the “initial” biofilm, each treatment had two biological replicates. Proteobacteria were classified down to the class level. The 30 most abundant taxa (ranked by maximum abundance) are shown, and the other taxa are included under the classification of “Others.”