Photomixotrophic growth of Rhodobacter capsulatus SB1003 on ferrous iron
- Creators
-
Kopf, S. H.
-
Newman, D. K.
Abstract
This study investigates the role iron oxidation plays in the purple non-sulfur bacterium Rhodobacter capsulatus SB1003. This organism is unable to grow photoautotrophically on unchelated ferrous iron [Fe(II)] despite its ability to oxidize chelated Fe(II). This apparent paradox was partly resolved by the discovery that SB1003 can grow photoheterotrophically on the photochemical breakdown products of certain ferric iron–ligand complexes, yet whether it could concomitantly benefit from the oxidation of Fe(II) to fix CO_2 was unknown. Here, we examine carbon fixation by stable isotope labeling of the inorganic carbon pool in cultures growing phototrophically on acetate with and without Fe(II). We show that R. capsulatus SB1003, an organism formally thought incapable of phototrophic growth on Fe(II), can actually harness the reducing power of this substrate and grow photomixotrophically, deriving carbon both from organic sources and from fixation of inorganic carbon. This suggests the possibility of a wider occurrence of photoferrotrophy than previously assumed.
Additional Information
© 2011 Blackwell Publishing Ltd. Received 19 April 2011; accepted 16 November 2011. Article first published online: 29 Dec. 2011. We thank Alexandre Poulain for teaching S.K. how to work with R. capsulatus and Alexa Price-Whelan and other members of the Newman Lab for stimulating discussions. Three anonymous reviewers are gratefully acknowledged for constructive criticism. This work was supported by grants to D.K.N. from the National Science Foundation (grant MCB- 0616323) and the Howard Hughes Medical Institute. D.K.N. is an Investigator of the Howard Hughes Medical Institute.Attached Files
Accepted Version - nihms400410.pdf
Files
Name | Size | Download all |
---|---|---|
md5:844f15f1fe66b94b1ca75dc183133a8e
|
524.7 kB | Preview Download |
Additional details
- PMCID
- PMC4587904
- Eprint ID
- 31320
- DOI
- 10.1111/j.1472-4669.2011.00313.x
- Resolver ID
- CaltechAUTHORS:20120507-075239308
- NSF
- MCB-0616323
- Howard Hughes Medical Institute (HHMI)
- Created
-
2012-05-08Created from EPrint's datestamp field
- Updated
-
2021-11-09Created from EPrint's last_modified field
- Caltech groups
- Division of Geological and Planetary Sciences