Table 3.
List of the 15 most abundant undermat members (based on 16S rRNA gene amplicon sequence abundance) their relative abundance, predicted metabolic life style, and relationship to oxygen.
| OTU | Identity | Rel. abundance* (%) | Predicted metabolic lifestyle | Relationship to oxygen |
|---|---|---|---|---|
| OTU-01 | Chloroflexi, Roseiflexus sp. | 49 | Anoxygenic photomixotroph | Oxygen tolerant |
| OTU-02 | Thermotogae, Pseudothermotoga sp. | 10 | Chemoheterotroph, fermentation | Anaerobe |
| OTU-03 | Armatimonadetes (OP10) (OS Type L) | 4 | Chemoheterotroph, respiration, fermentation | Facultative anaerobe |
| OTU-04 | Aquificae, Thermocrinis sp. | 4 | Chemoautotroph, sulfur-oxidation | Aerobe |
| OTU-05 | Cyanobacteria, Synechococcus sp. B' | 4 | Oxygenic photoautotroph | Aerobe |
| OTU-06 | Chloroflexi, Ca. Roseilinea gracile | 3 | Anoxygenic photoheterotroph | Aerobe |
| OTU-07 | Atribacteria (OP9) | 2 | Chemoheterotroph, fermentation | Anaerobe |
| OTU-08 | Nitrospirae, Thermodesulfovibrio sp. | 2 | Dissimilatory sulfate-reduction | Anaerobe |
| OTU-09 | Chloroflexi, Anaerolinea-like | 1 | Chemoautotroph | Anaerobe |
| OTU-10 | Themotogae, EM3 | 1 | Chemoheterotroph, respiration | Aerobe |
| OTU-11 | Chloroflexi, Chloroflexus sp. | 1 | Anoxygenic photoauto/mixotroph | Oxygen-tolerant |
| OTU-12 | Armatimonadetes (OP10), Group 6 | 1 | Chemoheterotroph, anaerobe respiration | Anaerobe |
| OTU-13 | Aminicenantes (OP8) | 1 | Chemoheterotroph, fermentation | Anaerobe |
| OTU-14 | Planctomycetes | 1 | Chemoautotroph | Facultative anaerobe |
| OTU-15 | Chloroflexi, “Ca. Chloranaerofilum corporosum” | 1 | Anoxygenic photoauto/mixotroph | Strict anaerobe |
*
Based on 16S rRNA amplicon sequence abundance (Thiel et al., 2016).