title: Production of biohydrogen by heterologous expression of oxygen-tolerant Hydrogenovibrio marinus [NiFe]-hydrogenase in Escherichia coli.
abstract: Oxygen sensitivity of hydrogenase is a critical issue in efficient biological hydrogen production. In the present study, oxygen-tolerant [NiFe]-hydrogenase from the marine bacterium, Hydrogenovibrio marinus, was heterologously expressed in Escherichia coli, for the first time. Recombinant E. coli BL21 expressing H. marinus [NiFe]-hydrogenase actively produced hydrogen, but the parent strain did not. Recombinant H. marinus hydrogenase required both nickel and iron for biological activity. Compared to the recombinant E. coli [NiFe]-hydrogenase 1 described in our previous report, recombinant H. marinus [NiFe]-hydrogenase displayed 1.6- to 1.7-fold higher hydrogen production activity in vitro. Importantly, H. marinus [NiFe]-hydrogenase exhibited relatively good oxygen tolerance in analyses involving changes of surface aeration and oxygen proportion within a gas mixture. Specifically, recombinant H. marinus [NiFe]-hydrogenase produced ∼7- to 9-fold more hydrogen than did E. coli [NiFe]-hydrogenase 1 in a gaseous environment containing 5-10% (v/v) oxygen. In addition, purified H. marinus [NiFe]-hydrogenase displayed a hydrogen evolution activity of ∼28.8 nmol H₂/(minmg protein) under normal aerobic purification conditions. Based on these results, we suggest that oxygen-tolerant H. marinus [NiFe]-hydrogenase can be employed for in vivo and in vitro biohydrogen production without requirement for strictly anaerobic facilities.
authors.affiliation: Department of Chemical Engineering, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea.
authors.forename: Jaoon Y H
authors.initials: JY
authors.lastname: Kim
authors.forename: Byung Hoon
authors.initials: BH
authors.lastname: Jo
authors.forename: Hyung Joon
authors.initials: HJ
authors.lastname: Cha
mesh_terms: D000332:Aerobiosis; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015153:Blotting, Western; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D006859:Hydrogen / Q000032:analysis / Q000378:metabolism*; D006864:Hydrogenase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D007501:Iron / Q000378:metabolism; D008969:Molecular Sequence Data; D009532:Nickel / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism; D044147:Piscirickettsiaceae / Q000201:enzymology* / Q000235:genetics; D021382:Protein Sorting Signals; D021122:Protein Subunits / Q000737:chemistry; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D021382:Protein Sorting Signals; D021122:Protein Subunits; D011994:Recombinant Proteins; D009532:Nickel; D006859:Hydrogen; D007501:Iron; C043296:nickel-iron hydrogenase; D006864:Hydrogenase; D010100:Oxygen