Table 1.

Yellowstone Lake vent samples: summary of chemistry, dark C fixation, and 16S rRNA gene sequence data.

Sampling location and sample code	Mary Bay West 12 MBW	Mary Bay Canyon 28 V03-13P	Stevenson Island 72 V03-28P	West Thumb Canyon 129 V03-46P	West Thumb 98 V03-36P	Yellowstone Lake station LW-02
Sample volume and date	310 mL 7-16-03	190 mL 7-18-03	303 mL 7-22-03	150 mL 7-29-03	303 mL 7-25-03	N/A 7-1-03
Water depth (m)	1	47.9	109.3	52.4	21.7	0
Temperature (°C)	19	49	110	77	16	Ambient
DOC (mg/l)	1.77	1.89	n.d.	n.d.	1.45	n.d.
H2S (μM)	2.2	119.3	59.5	17.2	0.7	0
${\text{SO}}_{\text{3}}^{\text{2-}}$ (μM)	1.3	4.5	5.3	8.4	3.7	0
${\text{S}}_{\text{2}}{\text{O}}_{\text{3}}^{\text{2-}}$ (μM)	0.1	1.4	19.9	1.52	0.5	0
${\text{SO}}_{\text{4}}^{\text{2-}}$ (μM)	104	122	93	187	86	83
${\text{NH}}_{\text{4}}^{\text{+}}$ (μM)	1.5	12.7	11.0	8.8	0.0	0.7
${\text{NO}}_{\text{3}}^{\text{−}}+{\text{NO}}_{\text{2}}^{\text{−}}$ (μM)	0.1	0.2	0.9	1.0	0.0	0.0
SRP (μM)	0.21	1.84	0.68	2.51	0.59	0.32
SiO2 (μM)	192	325	197	1865	159	178
Cl− (μM)	146	210	132	1971	156	125
Summary of dark CO2 fixation rates (μM C h−1)	1.08, 15°C 6.46, 15°C with S	1.7 at 15°C 8.6 at 60°C no. S stimulation	<0.01, 15°C 0.4 at 50°C 0.67 at 60°C	Near 0.1 at 50 and 60°C 0.83–1.66, with S, 60°C	Near 0.003 with S, 50°C < 0.003 otherwise	0.003
No. of bacterial 16S rRNA gene sequences	44	23	37	54	38
Aquificales	–	2	16	13	–
Gammaproteobacteria	21	5	1	–	1
Betaproteobacteria	8	3	6	10	13
Alphaproteobacteria	1	1	–	–	–
Deltaproteobacteria	–	7	–	–	–
Epsilonproteobacteria	–	1	–	–	–
Actinobacteria	6	–	7	10	16
Planctomycetales	–	–	4	–	2
CFB phylum	2	1	–	3	–
Chloroflexi	2	–	–	6	1
Acidobacteria	–	3	–	–	–
Cyanobacteria	2	–	1	–	3
Thermodesulfovibrio	–	–	–	7	–
Verrucomicrobium	1	–	2	–	2
OP10	1	–	–	–	–
Chlorobia	–	–	–	2	–