Fig. 4

Relative abundances of transcripts associated with the in situ functional activities of the three sediment sample communities receiving enrichment treatment. Genes involved with environment stress resistance, glycolysis/gluconeogenesis (KO00010), the citrate cycle (TCA cycle, KO00020), the pentose phosphate pathway (KO00030), oxidative phosphorylation (KO00190), nitrogen metabolism (KO00910), sulfur metabolism (KO00920), amino acid metabolism (KO00250, KO00260, KO00280), ABC transporters (KO02010), two-component systems (KO02020), flagellar assembly (KO02040), and the bacterial secretion system (KO03070). Light blue indicates the control treatment, and orange indicates 5 days of enrichment culturing. Gray indicates 12 days of enrichment culturing, yellow indicates 21 days of enrichment culturing, and dark blue indicates 30 days of enrichment culturing. The size of a pie slice indicates the total fragments per kilobase of transcript per million fragments mapped (FPKM) of the corresponding gene in each sediment sample. HGD, S, and XSD indicate the three marine sediment samples