Figure 6.

Relationship between selenium utilization traits and environmental factors (oxygen concentration and optimal growth temperature). Organisms were classified into four groups, including those containing the following: the Sec trait only, both Sec and selenouridine traits, selenouridine trait only, and no selenium utilization traits. (a) Distribution of organisms with different selenium utilization traits based on their requirement for oxygen. (b) Distribution of organisms with different selenium utilization traits based on their optimal growth temperature. (c) Distribution of organisms classified according to their oxygen requirement based on their selenium utilization traits. (d) Distribution of organisms classified according to their optimal growth temperature based on their selenium utilization traits.