Exploring the onset of B12-based mutualisms using a recently evolved Chlamydomonas auxotroph and B12-producing bacteria

Bunbury, Freddy, Deery, Evelyne, Sayer, Andrew P., Bhardwaj, Vaibhav, Harrison, Ellen L., Warren, Martin J. ORCID: https://orcid.org/0000-0002-6028-6456 and Smith, Alison G. (2022) Exploring the onset of B12-based mutualisms using a recently evolved Chlamydomonas auxotroph and B12-producing bacteria. Environmental Microbiology, 24 (7). pp. 3134-3147. ISSN 1462-2912

[thumbnail of Environmental Microbiology - 2022 - Bunbury - Exploring the onset of B12‐based mutualisms using a recently evolved]
Preview
PDF (Environmental Microbiology - 2022 - Bunbury - Exploring the onset of B12‐based mutualisms using a recently evolved) - Published Version
Available under License Creative Commons Attribution.

Download (1MB) | Preview

Abstract

Cobalamin (vitamin B12) is a cofactor for essential metabolic reactions in multiple eukaryotic taxa, including major primary producers such as algae, and yet only prokaryotes can produce it. Many bacteria can colonize the algal phycosphere, forming stable communities that gain preferential access to photosynthate and in return provide compounds such as B12. Extended coexistence can then drive gene loss, leading to greater algal–bacterial interdependence. In this study, we investigate how a recently evolved B12-dependent strain of Chlamydomonas reinhardtii, metE7, forms a mutualism with certain bacteria, including the rhizobium Mesorhizobium loti and even a strain of the gut bacterium E. coli engineered to produce cobalamin. Although metE7 was supported by B12 producers, its growth in co-culture was slower than the B12-independent wild-type, suggesting that high bacterial B12 provision may be necessary to favour B12 auxotrophs and their evolution. Moreover, we found that an E. coli strain that releases more B12 makes a better mutualistic partner, and although this trait may be more costly in isolation, greater B12 release provided an advantage in co-cultures. We hypothesize that, given the right conditions, bacteria that release more B12 may be selected for, particularly if they form close interactions with B12-dependent algae.

Item Type: Article
Additional Information: Funding Information: The authors are grateful for helpful discussions with Dr Payam Mehrshahi and Dr Katrin Geisler (University of Cambridge) and Dr Katherine Helliwell (Marine Biological Association of the UK) and technical support from Geraldine Heath and Lorraine Archer. This work was supported by: the UK's Biotechnology and Biological Sciences Research Council (BBSRC) Doctoral Training Partnership (grant no. BB/M011194/1) to F.B., A.P.S. and A.G.S.; BBSRC grant (BB/S002197/1) to M.J.W. and E.D.; the Gates Cambridge Trust (PhD scholarship to V.B.); the MELiSSA Foundation (FB European Space Agency) (grant no. CO-90-16-4078-02) to A.G.S. and E.H. Publisher Copyright: © 2022 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.
Uncontrolled Keywords: microbiology,ecology, evolution, behavior and systematics ,/dk/atira/pure/subjectarea/asjc/2400/2404
Faculty \ School: Faculty of Science
Related URLs:
Depositing User: LivePure Connector
Date Deposited: 21 Sep 2022 12:30
Last Modified: 24 Oct 2022 06:51
URI: https://ueaeprints.uea.ac.uk/id/eprint/88557
DOI: 10.1111/1462-2920.16035

Actions (login required)

View Item View Item