TABLE 4.
Substrate use by closest relatives of all 14 mcrA clusters, depth intervals and temperature ranges in which they were detected, and total number of mcrA clusters detected per depth layera
| Depth (cmbsf) | Temp (°C) | H2/HCO3−, formate |
MeOH, TMA |
Methane |
Unknownb |
No. of clusters (of 12) per depth layer | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Methanoplanusc | Methanomicrobiales mcrA seep cluster | GB Methanomicrobiales mcrA cluster | Methanocaldococcusc | Methanopyrusc,d | Methanohalophilusc | Methermicoccusc,e | ANME-1f | ANME-2f | Group e | DB Guaymas group II | DB Guaymas group III | |||
| 0–1 | 2–7 | + | + | + | − | + | + | + | + | + | + | + | + | 11 |
| 1–2 | 8–12 | − | + | + | + | + | + | + | + | + | − | + | + | 11 |
| 2–3 | 13–17 | − | − | + | − | + | + | + | − | + | − | + | + | 7 |
| 3–4 | 18–23 | − | − | + | − | + | − | + | − | − | − | + | + | 5 |
| 4–5 | 24–28 | − | − | + | − | + | + | − | − | + | − | + | + | 7 |
| 5–6 | 29–33 | + | + | + | + | + | − | − | − | + | − | + | + | 10 |
| 7–8 | 39–43 | − | − | − | − | + | − | − | − | − | − | + | − | 2 |
| 9–10 | 49–54 | − | − | − | − | − | − | − | − | − | − | + | − | 1 |
| 12–13 | 64–69 | − | − | − | − | − | − | − | − | − | − | − | − | 0 |
| 15–16 | 85–89 | − | − | − | − | − | − | − | − | − | − | − | − | 0 |
| 19–20 | 100–105 | − | − | − | − | − | − | − | − | − | − | − | − | 0 |
| No. of depth intervals | NA | 3 | 3 | 6 | 2 | 7 | 4 | 4 | 2 | 5 | 1 | 8 | 6 | NA |
a
Includes data obtained with all primers used in this study. Abbreviations and symbols: MeOH, methanol; TMA, trimethyl amine; +, detected; −, not detected; NA, not applicable.
b
Unknown, groups with no cultured relatives.
c
In pure culture.
d
Includes Methanopyrus mcrA subclusters I and II.
e
All three Methermicoccaceae genus level phylotypes are treated as one cluster in this table.
f
Not in pure culture; evidence from radiotracer studies.