Table 2. Comparing this work to previous reports for the production of the C. reinhardtii HydA1 hydrogenase.

Microbial host	C.r. HydA1 Variant	Specific Activity1	Purification Yield2	Iron Content3	Ref.
C. reinhardtii	HydA1	730±146	0.04	NR	[23]
	HydA1	935	0.001	3.9±0.3	[35]
S. oneidensis	Strep-tag II–HydA1	740±56	0.5	6.1±0.1	[26]
C. acetobutylicum	HydA1–Strep-tag II	625	1.0	NR	[27]
	HydA1–Strep-tag II	760	0.1	NR	[37]
E. coli	HydA1–Strep-tag II	150	1.0	NR	[24]
E. coli	HydA1– Strep- tag II	641±88	30±11	4.5±0.2	This Work

¹Specific activities for H₂ production rates are expressed in units of µmol H₂·min⁻¹·mg⁻¹ of HydA1.

²Purification yields are mg of HydA1 isolated per liter of cell culture.

³Iron content is expressed in units of Fe atoms per HydA1 peptide; NR, not reported.