Nickel-iron hydrogenases: Structural and functional properties

A Trinuclear [NiFe] Cluster Exhibiting Structural and Functional Key Features of [NiFe] Hydrogenases

“…Hydrogenases are essential for many microorganisms which receive energy by reduction of CO 2 , carbonates, sulfates, or nitrates 2. These enzymes are of great biotechnological interest3 owing to their capability to produce molecular hydrogen 4. [NiFe] hydrogenases are the most abundant of the four types, the [NiFe], [NiFeSe], Fe‐only, and metal‐free hydrogenases 3.…”

“…These enzymes are of great biotechnological interest3 owing to their capability to produce molecular hydrogen 4. [NiFe] hydrogenases are the most abundant of the four types, the [NiFe], [NiFeSe], Fe‐only, and metal‐free hydrogenases 3. 5 Figure 1 depicts the active center of hydrogenase from Desulfovibrio gigas .…”

Hydrogenase enzymes: Recent structural studies and active site models

“…Based on this and other spectroscopic data, detailed mechanisms for hydrogen activation involving hydrides of both Ni and Fe have been proposed [29,30]. Several computational studies at various levels of theory have been reported [31] (see Fig.…”

The metal‐free hydrogenase from methanogenic archaea: evidence for a bound cofactor

“…Many methanogenic archaea growing on H 2 and CO 2 contain an unusual hydrogenase without nickel or iron^sulfur clusters [1,2], which was designated metal-free hydrogenase in order to distinguish it from all other hydrogenases that are Fe/S or Ni/Fe/S proteins [3,4]. The metal-free hydrogenase, abbreviated Hmd, catalyzes the reversible reduction of methenyltetrahydromethanopterin with H 2 to methylenetetrahydromethanopterin (vG³P = 35.5 kJ/mol) which is an intermediate reaction in the pathway of methane formation from CO 2 and H 2 [5,6].…”