Table 1.

Operational taxonomic units (OTUs) highly expressing 16S rRNA after the 5-day anoxic incubation of nitrate-amended marine sediments.

OTU ID	Closely related species	Similarity (%)	Accession number	Phylum/Class	Family	Relative abundance (%)a	Increasing ratio (fold)b	Putative functionc
4053	Sulfurimonas denitrificans	98.4	NR121690	Epsilonproteobacteria	Helicobacteraceae	14.64	2421.7	Sulfur oxidation
566	Cellulomonas oligotrophica	98.8	KF817659	Actinobacteria	Cellulomonadaceae	2.60	430.2	Fermentation, nitrate reduction
13536	Thioalkalispira microaerophila	97.6	NR025239	Gammaproteobacteria	Thioalkalispiraceae	0.82	269.8	Sulfur oxidation
11183	Thioalbus denitrificans	96.8	NR122087	Gammaproteobacteria	Ectothiorhodospiraceae	0.43	143.1	Sulfur oxidation
8007	Geobacter bremensis	100	KF800712	Deltaproteobacteria	Geobacteraceae	6.78	93.5	Iron(III) reduction
3944	Thioalbus denitrificans	100	NR122087	Gammaproteobacteria	Ectothiorhodospiraceae	13.37	38.8	Sulfur oxidation
2401	Geothrix fermentans	99.2	NR036779	Acidobacteria	Holophagae	0.21	34.7	Iron(III) reduction
14834	Thioalbus denitrificans	96.8	NR122087	Gammaproteobacteria	Ectothiorhodospiraceae	0.20	33.7	Sulfur oxidation
7917	Thioprofundum lithotrophicum	95.2	NR112829	Gammaproteobacteria	Thioalkalispiraceae	0.09	30.7	Sulfur oxidation
2865	Pelobacter carbinolicus	95.2	NR075013	Deltaproteobacteria	Pelobacteraceae	0.09	28.6	Iron(III) reduction, sulfate reduction
425	Geobacter luticola	99.6	NR114303	Deltaproteobacteria	Geobacteraceae	6.02	26.5	Iron(III) reduction
20	Thioprofundum lithotrophicum	94.5	NR112829	Gammaproteobacteria	Thioalkalispiraceae	0.07	22.5	Sulfur oxidation
12681	Thioprofundum lithotrophicum	96.4	NR112829	Gammaproteobacteria	Thioalkalispiraceae	0.33	22.1	Sulfur oxidation
5722	Thioalkalispira microaerophila	96.8	NR025239	Gammaproteobacteria	Thioalkalispiraceae	10.17	21.4	Sulfur oxidation
15348	Thioprofundum lithotrophicum	95.3	NR112829	Gammaproteobacteria	Thioalkalispiraceae	0.31	17.4	Sulfur oxidation
13687	Desulfovibrio butyratiphilus	95.3	NR112679	Deltaproteobacteria	Desulfovibrionales	0.09	15.3	Butyrate oxidation, sulfate reduction
3917	Geobacter pelophilus	97.6	NR026077	Deltaproteobacteria	Geobacteraceae	0.12	12.9	Iron(III) reduction
14604	Desulfocapsa sulfexigens	93.3	KF952439	Deltaproteobacteria	Desulfobacterales	0.06	10.2	Sulfur disproportionation
12930	Thioalkalispira microaerophila	97.6	NR025239	Gammaproteobacteria	Thioalkalispiraceae	0.12	9.7	Sulfur oxidation
17265	Desulfomonile tiedjei	98.4	NR074118	Deltaproteobacteria	Syntrophaceae	0.09	7.7	Sulfate reduction
9626	Desulfobulbus mediterraneus	94.5	NR025150	Deltaproteobacteria	Desulfobulbaceae	4.05	6.2	Sulfate reduction
1714	Thioprofundum lithotrophicum	96.0	NR112829	Gammaproteobacteria	Thioalkalispiraceae	0.06	6.1	Sulfur oxidation

^aThe relative abundance of the 16S rRNA transcripts in the NT5 library. More than 0.05% of the abundance is shown.

^bThe increasing ratio was calculated from the relative abundance in the NT5 library to that in the CT5 library.

^cThe putative function was determined by the reported physiology of the closely related species.