Fig. 1

Taxonomic and functional profile of free-living (FL) and marine snow-attached (MA) communities in the marine snow culture system. a Alpha-diversity (Shannon index) of taxonomic and b functional composition in the FL and MA communities at both the gene and protein levels. F, significant difference in the FL fraction between the gene and protein levels (P < 0.05‒0.01); M, significant difference in the MA fraction between the gene and protein levels (P < 0.01); D, significant difference in the metagenome between the FL and MA communities (P < 0.01); P, significant difference in the metaproteome between the FL and MA communities (P < 0.05‒0.01). c Bray–Curtis dissimilarity in taxonomy and d function between the FL and MA communities at both the gene and protein levels. The boxes show the mean, median, and interquartile range (IQR); the whiskers show 1.5 times the IQR of the lower and upper quartiles or the data range. **P < 0.01. e Scatter pie charts showing the compositions and relative abundances of the gene- and f protein-based taxonomic contribution to the major functions, including C, E, J, O, and P categories, based on the Clusters of Orthologous Groups (COGs) database at the phylum level (order level for Alpha- and Gammaproteobacteria and class level for other proteobacteria). C, control community