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.