Appendix Table 1. List of m/z values used for internal calibration. These compounds were
chosen because they occur in all DOM mass spectra that have been analyzed by this lab. We are
confident about the elemental formula assignments due to the lack of reasonable alternatives (the
other series that would work has N4O4 instead of O8) and the consistent error of observed m/z
values within the experimental spectra (for example, the error in mass accuracy of the observed
values were approximately 2 ppm + 0.2 ppm).
Formula [M-H]C20H25O8C21H27O8C22H29O8C23H31O8C24H33O8C25H35O8C26H37O8C27H39O8C28H41O8C29H43O8-
Exact mass
393.15494278
407.17059284
421.18624290
435.20189297
449.21754303
463.23319310
477.24884316
491.26449322
505.28014329
519.29579335
Appendix Table 2. Indicator compounds for Group 1. All compounds were identified as indicators in both data transformations. For
each compound, the following information is presented: observed m/z value; neutral mass (observed m/z + H); elemental formula as
determined with the algorithm described in the text; the error between the observed neutral mass and the theoretical mass calculated
from the elemental formula; the relative peak height of the compound in each cruise sample spectrum; the indicator and p-values from
ISA analysis; and the relative peak height of the compound in SAR11 laboratory incubations. The threshold peak height levels are
shown in Table 1. Bold font indicates compounds which are enriched at least 2X over the control in the P. ubique dataset.
Observed
m/z
341.16012
385.18632
401.18114
415.19676
436.16081
443.22809
456.15875
456.19508
460.16412
461.14797
462.21280
463.12172
470.21067
471.15026
488.19215
492.18686
499.12162
499.25424
501.23359
514.21555
515.21277
515.24918
526.23711
529.22850
543.24431
554.23190
571.23923
Neutral
mass
342.16795
386.19415
402.18896
416.20458
437.16863
444.23591
457.16657
457.20291
461.17195
462.15580
463.22062
464.12954
471.21850
472.15808
489.19998
493.19469
500.12944
500.26207
502.24142
515.22338
516.22060
516.25701
527.24494
530.23632
544.25213
555.23972
572.24706
Elemental
Formula
C17H26O7
C19H30O8
C19H30O9
C20H32O9
C21H27O9N1
C22H36O9
C2013C1H28O11
C2113C1H32O10
C20H31O9N1S1
C20H30O10S1
C24H33O8N1
C26H24O6S1
C2213C1H34O10
C21H28O12
C25H31O9N1
C24H31O10N1
C29H24O6S1
C25H40O10
C24H38O11
C22H37O5N5S2
C24H36O12
C25H40O11
C20H41O7N5S2
C25H38O12
C26H40O12
C2613C1H38O12
C27H40O13
Error
(ppm)
0.27
0.20
0.05
0.12
0.11
0.05
0.12
0.01
0.01
0.37
0.01
0.39
-0.12
0.01
0.19
0.23
0.17
0.16
0.01
0.45
0.15
0.11
0.38
0.01
0.28
0.07
0.29
Stn 2
0m
6.3
10.8
8.3
8.7
6.2
6.1
6.9
9.2
6.8
7.8
6.8
7.8
7.3
9.2
5.9
5.7
5.7
6.1
5.8
6.1
8.6
7.2
7.5
8.1
7.5
7.0
7.3
Gp 1
Stn 5
0m
7.4
9.1
6.8
8.4
6.2
8.2
6.3
8.7
13.4
8.6
6.8
8.9
8.4
6.7
6.6
6.3
7.6
7.9
6.3
6.2
7.1
7.0
7.4
7.9
7.1
7.0
6.2
Stn 5
43m
6.6
9.0
6.3
8.0
7.2
6.3
6.5
8.4
9.4
6.3
7.9
10.4
7.2
7.6
9.3
6.2
7.9
6.5
6.3
6.8
8.7
7.8
6.4
7.9
7.1
7.9
8.9
Stn 7
0m
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Gp 2
Stn 9
0m
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Gp 3
Stn 2
1000m
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
IV
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
pvalue
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
SAR11
Control
0
0
0
0
0
0.6
0
0
0
0
0.6
0
0.6
0
0.5
0
0
0.5
0.6
0.8
0.5
0.6
0.9
0.6
0.6
0
0.6
SAR11
Light
0
0
0
0
0.6
0.9
0
0.8
0
0
1.1
0.6
1.1
0
1.1
1.1
0.9
0.9
1.1
1.3
0.9
0.9
1.7
1.4
1.0
0
1.2
SAR11
Dark
0
0
0
0
0
0
0
0
0
0
1.0
0
0
0
1.3
1.0
1.1
0.9
1.1
1.6
0.9
1.1
1.6
1.3
1.0
0
1.0
Observed
m/z
595.20279
601.30143
623.23425
633.29095
812.64037
Neutral
mass
596.21062
602.30926
624.24208
634.29878
813.6482
Elemental
Formula
C28H36O14
C33H46O10
C30H40O14
C33H46O12
C50H87O7N1
Error
(ppm)
0.18
0.26
0.44
0.23
0.07
Stn 2
0m
7.2
7.6
8.6
9.0
5.0
Gp 1
Stn 5
0m
6.5
8.2
7.7
10.0
11.1
Stn 5
43m
6.9
9.0
8.5
9.3
6.5
Stn 7
0m
0
0
0
0
0
Gp 2
Stn 9
0m
0
0
0
0
0
Gp 3
Stn 2
1000m
0
0
0
0
0
IV
100
100
100
100
100
pvalue
0.042
0.042
0.042
0.042
0.042
SAR11
Control
0
1.0
0.6
0
0
SAR11
Light
1.0
1.6
1.1
0.6
0
SAR11
Dark
0
1.6
0
0
0
Appendix Table 3. Indicator compounds for Group 2. These compounds were determined by ISA as described in the text.
Compounds that were identified by peak-height-based ISA only are indicated in italics. For each compound, the following information
is presented: observed m/z value; neutral mass (observed m/z + H); elemental formula as determined with the algorithm described in
the text; the error between the observed neutral mass and the theoretical mass calculated from the elemental formula; the relative peak
height of the compound in each cruise sample spectrum; the indicator and p-values from ISA analysis; and the relative peak height of
the compound in SAR11 laboratory incubations. The background peak height (i.e., noise) levels are shown in Table 1. Pairs of 12C /
13
C isomers are indicated with numerical superscripts. Compounds enriched in the P. ubique dataset are shown in bold.
Observed
m/z
349.20152
410.04220
441.26411
443.27977
445.29547
447.27468
451.17570
451.24846
453.22779
455.17395
455.24339
455.27976
457.18948
457.25905
457.29543
459.27464
461.29030
465.19121
467.24329
469.25902
471.274631
471.31105
472.278081
473.29031
475.30599
479.20696
Neutral
mass
350.20935
411.05003
442.27194
444.2876
446.30329
448.2825
452.18353
452.25629
454.23562
456.18178
456.25122
456.28758
458.1973
458.26687
458.30325
460.28247
462.29812
466.19904
468.25111
470.26685
472.28246
472.31887
473.2859
474.29814
476.31382
480.21479
Elemental
Formula
C20H30O5
C23H13O1N3S2
C27H38O5
C27H40O5
C27H42O5
C26H40O6
C26H28O7
C28H36O5
C27H34O6
C22H32O8S1
C27H36O6
C28H40O5
C22H34O8S1
C27H38O6
C28H42O5
C27H40O6
C27H42O6
C27H30O7
C28H36O6
C28H38O6
C28H40O6
C29H44O5
C2713C1H40O6
C28H42O6
C28H44O6
C28H32O7
Error
(ppm)
0.07
0.07
0.03
0.05
0.15
0.03
0.06
0.02
0.18
0.02
0.06
0.01
0.30
0.08
0.06
0.04
0.04
0.25
0.16
0.02
0.06
0.00
0.12
0.01
0.06
0.04
Stn 2
0m
6.8
0
6.8
8.3
7.0
13.4
0
0
9.0
0
12.4
5.9
0
16.7
6.1
16.2
15.1
0
6.3
8.6
12.8
4.9
0
13.4
8.8
0
Gp 1
Stn 5
0m
9.3
0
11.2
12.9
13.2
19.4
0
0
12.8
0
20.7
11.3
0
26.5
14.1
26.6
25.6
0
11.6
14.4
21.3
11.5
0
22.8
20.0
0
Stn 5
43m
7.8
0
8.0
7.5
6.1
11.9
0
0
9.8
0
14.2
7.3
0
18.2
7.7
16.8
12.3
0
8.5
11.1
14.0
6.9
0
14.6
9.6
0
Gp 2
Stn 7
Stn 9
0m
0m
10.4
16.7
12.8
51.9
16.7
18.7
21.1
21.5
16.8
19.6
29.7
24.3
10.3
11.3
10.8
14.4
23.3
23.5
12.2
10.3
32.0
32.7
20.8
24.4
9.7
10.8
42.0
38.8
19.8
25.7
42.1
35.4
31.9
30.2
11.4
12.1
18.3
19.2
27.9
24.4
36.1
33.0
20.0
22.9
10.7
10.4
33.2
29.6
20.7
21.1
12.1
10.1
Gp 3
Stn 2
1000m
0
0
0
6.2
0
7.8
0
0
8.4
0
11.1
0
0
14.0
0
11.3
8.4
0
8.0
9.0
9.0
0
0
9.1
0
0
IV
63
100
67
58
67
54
100
100
55
100
55
74
100
54
71
55
54
100
53
56
58
73
100
55
62
100
pvalue
0.020
0.060
0.035
0.020
0.035
0.035
0.060
0.060
0.020
0.060
0.020
0.035
0.060
0.020
0.035
0.035
0.056
0.060
0.049
0.041
0.020
0.035
0.060
0.035
0.035
0.060
SAR11
Control
0.8
0
0.5
0.7
0
1.1
0.6
0
1.2
0
1.6
0.6
0
1.8
0.5
1.8
1.0
1.0
0.7
1.1
1.2
0
0
1.0
0.8
0
SAR11
Light
1.0
0
0
0.8
0
1.4
1.0
0
1.5
0
1.9
0.6
0
2.2
0
2.1
1.2
1.9
0.9
1.5
1.5
0
0
1.1
0.9
0.6
SAR11
Dark
0
0
0
0.8
0
1.5
0.9
0
1.5
0
1.7
0
0
2.1
0
2.3
1.2
1.6
0.9
1.5
1.6
0
0
1.3
1.0
0.8
Observed
m/z
481.18622
483.20516
483.27462
483.31109
485.25392
485.290362
486.293752
487.269583
487.30610
488.272853
489.28522
489.32163
491.30081
495.29565
497.25393
497.29033
499.26950
499.305924
500.309264
501.285295
501.321686
502.288675
502.325006
503.300787
503.33723
504.304177
505.31652
509.18097
509.25388
511.20002
511.26949
511.29056
513.28511
Neutral
mass
482.19405
484.21299
484.28244
484.31892
486.26174
486.29819
487.30158
488.2774
488.31393
489.28067
490.29305
490.32946
492.30864
496.30347
498.26176
498.29816
500.27732
500.31374
501.31709
502.29312
502.32951
503.2965
503.33283
504.30861
504.34506
505.312
506.32434
510.18880
510.26171
512.20785
512.27732
512.29838
514.29293
Elemental
Formula
C27H30O8
C24H36O8S1
C29H40O6
C30H44O5
C28H38O7
C29H42O6
C2813C1H42O6
C28H40O7
C29H44O6
C2713C1H40O7
C28H42O7
C29H46O6
C28H44O7
C27H44O8
C29H38O7
C30H42O6
C29H40O7
C30H44O6
C2913C1H44O6
C29H42O7
C30H46O6
C2813C1H42O7
C2913C1H46O6
C29H44O7
C30H48O6
C2813C1H44O7
C29H46O7
C28H30O9
C30H38O7
C25H36O9S1
C30H40O7
C27H44O9
C30H42O7
Error
(ppm)
0.04
0.21
0.09
0.08
0.02
0.10
0.17
0.00
0.28
-0.18
0.01
0.04
0.14
0.29
0.01
0.03
0.16
0.09
-0.12
0.13
0.13
0.18
0.07
0.20
0.06
-0.12
0.02
0.37
0.09
0.30
0.17
0.30
0.24
Stn 2
0m
5.2
0
6.6
0
18.3
7.7
0
19.8
8.1
6.8
21.1
7.7
13.1
6.8
10.1
0
13.1
5.0
0
18.3
7.1
5.2
0
17.6
7.0
5.0
13.2
0
5.8
0
7.7
7.1
8.8
Gp 1
Stn 5
0m
7.3
0
11.2
0
27.5
17.1
0
31.0
16.5
8.5
31.4
15.7
20.5
8.6
16.3
9.6
21.4
10.0
0
31.6
15.5
7.7
0
27.5
14.1
9.4
21.7
0
9.2
0
11.5
10.6
17.0
Stn 5
43m
7.0
0
7.2
0
21.3
12.6
0
25.3
10.5
7.9
23.0
8.7
11.6
6.9
14.2
7.3
18.2
8.9
0
25.4
11.9
6.5
0
22.0
9.2
7.7
14.9
0
9.6
0
9.8
7.4
14.2
Gp 2
Stn 7
Stn 9
0m
0m
14.6
11.9
11.4
10.4
25.1
22.3
16.7
12.6
43.7
35.3
35.2
33.6
12.7
9.2
48.4
36.1
35.0
32.1
15.4
11.2
44.4
35.6
22.6
23.1
24.2
21.4
10.6
12.0
26.9
24.6
22.5
18.2
35.7
32.9
30.1
27.9
12.0
9.3
53.4
45.8
47.3
38.5
15.2
13.7
13.0
12.9
46.7
40.5
30.9
28.4
15.5
14.3
29.9
25.3
10.3
10.4
15.4
14.3
10.4
9.4
18.6
16.1
11.3
20.0
34.6
26.5
Gp 3
Stn 2
1000m
0
0
0
0
16.8
0
0
14.9
0
0
14.2
0
7.1
0
11.9
0
11.2
0
0
14.2
0
0
0
9.7
0
0
0
0
0
0
0
0
9.1
IV
67
100
74
100
50
73
100
51
74
63
50
68
51
60
50
78
54
78
100
56
79
69
100
58
75
67
62
100
64
100
64
65
58
pvalue
0.020
0.060
0.020
0.060
0.020
0.035
0.060
0.020
0.035
0.020
0.035
0.035
0.035
0.020
0.041
0.064
0.020
0.020
0.060
0.020
0.020
0.020
0.060
0.020
0.035
0.035
0.035
0.060
0.020
0.060
0.020
0.035
0.041
SAR11
Control
0.9
0
0.8
0
1.7
0.7
0
2.6
0
1.0
2.2
0.8
1.1
0.8
1.5
0.5
1.3
0
0
2.4
0.8
0.8
0
1.7
0.5
0.6
1.1
0.7
1.0
0
1.1
0.9
0.7
SAR11
Light
1.5
0
1.1
0
2.4
1.0
0
3.7
0
1.1
2.8
0
1.4
1.0
2.1
0.6
1.8
0
0
3.2
0.9
1.0
0
2.2
0.6
0.8
1.4
1.1
1.1
0.6
1.5
1.2
1.1
SAR11
Dark
1.5
0
1.1
0
2.8
1.2
0
4.1
0
1.5
3.2
1.0
1.9
1.2
2.2
0
2.5
0.8
0
4.0
1.3
1.2
0
2.9
1.0
0.9
1.8
1.3
1.3
0
1.6
1.3
1.5
Observed
m/z
515.30079
517.31653
519.33219
525.17607
529.17080
531.29578
531.33215
533.31142
535.32710
541.28009
543.29582
545.31136
549.30639
551.32204
556.00140
565.28347
567.25953
634.66673
Neutral
mass
516.30862
518.32436
520.34002
526.1839
530.17863
532.30361
532.33998
534.31925
536.33493
542.28791
544.30364
546.31918
550.31422
552.32987
557.00922
566.29130
568.26735
635.67456
Elemental
Formula
C30H44O7
C30H46O7
C30H48O7
C28H30O10
C27H30O11
C30H44O8
C31H48O7
C30H46O8
C30H48O8
C31H42O8
C31H44O8
C31H46O8
C30H46O9
C30H48O9
-C30H46O8S1
C32H40O9
--
Error
(ppm)
0.17
0.00
0.02
0.00
0.34
0.03
0.05
0.04
0.02
0.10
0.05
0.16
0.06
0.06
-0.07
0.21
--
Stn 2
0m
12.7
12.2
10.7
0
0
19.5
0
14.0
10.7
5.7
6.1
5.1
12.3
5.8
0
0
4.7
52.4
Gp 1
Stn 5
0m
23.8
23.3
18.3
0
0
30.5
0
23.1
15.4
10.3
11.0
8.6
18.1
8.6
0
0
7.7
68.0
Stn 5
43m
20.6
17.9
12.4
0
0
26.5
0
20.7
11.0
9.9
9.7
7.6
16.4
7.5
0
0
8.2
69.4
Gp 2
Stn 7
Stn 9
0m
0m
55.9
39.9
53.4
42.7
31.8
24.0
9.4
9.6
16.7
9.9
52.2
36.4
10.5
10.0
41.1
30.5
25.7
21.2
14.8
11.6
15.4
14.8
15.5
13.8
28.4
19.4
11.8
11.6
10.6
10.4
9.3
9.4
13.2
11.5
100.6
100.6
Gp 3
Stn 2
1000m
9.9
7.6
0
0
0
14.3
0
8.7
0
0
0
0
0
0
0
0
0
0
IV
62
65
67
100
100
53
100
56
65
61
63
67
61
61
100
100
64
61
pvalue
0.020
0.020
0.035
0.060
0.060
0.020
0.060
0.020
0.035
0.035
0.035
0.020
0.020
0.035
0.060
0.060
0.020
0.020
SAR11
Control
1.4
1.6
0.7
0.8
1.0
2.3
0
1.5
0.6
1.2
1.0
0.7
0.6
0.5
3.6
0
1.1
0
SAR11
Light
2.0
2.1
1.0
1.4
2.4
3.0
0
1.9
0
1.5
1.3
1.0
0.8
0.7
1.7
0
1.4
0
SAR11
Dark
2.5
2.7
1.2
1.4
2.4
3.6
0
2.4
0.9
1.7
1.4
1.0
0.9
0
2.4
0
1.6
0