Table 2. Carbonic anhydrase specific activities of the recombinant proteins measured at pH 7.5 and pH 8.3.

Protein	Carbonic anhydrase specific activity (U mg−1)
	pH 7.5	pH 8.0	pH 8.3
psCA1	401±39*		750±14
psCA2	21±2		29±2
psCA3	nd†		26±3
Caba‡		39
acCAb		5236
CsoSCAc		3.41±0.08
baCAd§			737.9

^*sd (n = 3).

^†No activity was detected.

^‡Published records include β-class CAs from: a, Me. thermoautotrophicum (Smith & Ferry, 1999); b, Acetobacterium woodii (BrausStromeyer et al., 1997); c, Thimicrospira srunogenam (Dobrinski et al., 2010); d, Ba. subtilis SA3 (Ramanan et al., 2009).

^§Proteins were named in this study.