Microorganisms are often, genetically, metabolically versatile, which can lead to advantages in diverse environments, or when faced with environmental disturbances, intra or interspecific competetion for ressources such as nutrients.
One such organism is the metabolically diverse Sideroxydans sp. CL21, a close relative of the model Fe(II)-oxidizer SIderoxydans ES-1. Prior analysis showed that CL21 possesses the genetic potential for greater metabolic flexibility compared to its relative ES-1, including Sulfate oxidation as well as Lactate and Acetate oxidation as a means of heterotrophic growth. This potentially renders CL21 a viable organism to study mixtotrophy, and niche differentiation in microorganisms.
One such organism is the metabolically diverse Sideroxydans sp. CL21, a close relative of the model Fe(II)-oxidizer SIderoxydans ES-1. Prior analysis showed that CL21 possesses the genetic potential for greater metabolic flexibility compared to its relative ES-1, including Sulfate oxidation as well as Lactate and Acetate oxidation as a means of heterotrophic growth. This potentially renders CL21 a viable organism to study mixtotrophy, and niche differentiation in microorganisms.
[Picture]
Overview of the metabolic capacities and the related genes in the Fe(II)-oxidizers Sideroxydans ES-1 and sp. CL21.
Key findings:
- Near all substrates tested (minus acetate) could be metabolized by CL21
- We found clear hints at substrate preference in substrate-combination setups
- This metabolic flexibility likely reflects its ability to switch between substrates to adapt to its environmental and competitive needs
[Picture]
Distribution of (A) geochemical gradients at the field site, and (B) the likely favored metabolic strategies at different depths, in relation to (C) the relative of abundance of CL21 and other Fe(II)-oxidizers at various depths.
Publications
R. Cooper, J. Finck, C. Chan, K. Küsel
FEMS Microbiology Ecology, 2023