Table 1. Comparative genomics of thiamin biosynthesis in the Pelagibacterales.

Strain	thiC	thiD	thiE_0583a	thiE_0360a	thiF	thiS	thiG	csdBb	thiL	thiB	tenA
Ca. P. ubique	Absent	637671479	637671458	637671224	637671266	637671603	637671604	637671616	637671913	Absent	Absent
HTCC1002	Absent	639129819	639129840	639130075	639130033	639129702	639129701	639130662, 639129689	639130810	Absent	Absent
HTCC7211	Absent	2503353714	2503353735	2503352435	2503352394	2503352877	2503352878	2503352890	2503353193	Absent	Absent
HTCC9565	Absent	2503364149	2503364170	2503364413	2503364372	2503364883	2503364884	2503364896	2503365124	Absent	Absent
HIMB5	Absent	2504109247	2504109269	2504109551	2504109508	2504108506	2504108507	2504108519, 2504109389	2504108893	Absent	Absent
HIMB114	Absent	2503356000	2503356022	2503356319	2503356274	2503355884	2503355883	2503355872	Absent	Absent	Absent
IMCC9063	Absent	2505688345	2505688367	2505687345	2505687250	2505687878	2505687879	2505688259	Absent	Absent	2505687352
HIMB59	Absent	Absent	Absent	Absent	2504110146	Absent	Absent	2504110964	2504110802	2504111022	Absent

Gene numbers are IMG/ER Gene IDs (https://img.jgi.doe.gov/er).

^aThere are two copies of thiE in Ca. P. ubique: SAR11_0583 and SAR11_0360.

^bcsdB is predicted to encode the cysteine desulfurase activity necessary for thiazole biosynthesis (see Supplementary Methods).