The α-carbonic anhydrase (CA, EC 4.2.1.1) from the newly discovered thermophilic bacterium Sulfurihydrogenibium yellowstonense YO3AOP1 (SspCA) was investigated for its activation with a series of amino acids and amines. D-His, L-Phe, L-Tyr, L- and D-Trp were the most effective SspCA activators, with activation constants in the range of 1-12 nM, whereas L-His, L/D-DOPA, D-Tyr, and several biogenic amines/catecholamines were slightly less effective activators (K(A) in the range of 37 nM-0.97 μM). The least effective SspCA activator was d-Phe (K(A) of 5.13 μM). The thermal stability, robustness and very high catalytic activity of SspCA make this enzyme an ideal candidate for biomimetic CO(2) capture processes.