In vitro activation of [FeFe] hydrogenase: new insights into hydrogenase maturation.
The in vitro activation of the [FeFe] hydrogenase is accomplished by combining Escherichia coli cell extracts containing the heterologously expressed inactive HydA with extracts in which hydrogenase-specific maturation proteins HydE, HydF, and HydG are expressed in concert. Interestingly, the process of HydA activation occurs rapidly and in the absence of potential substrates, which suggests that the hydrogenase accessory proteins synthesize an H-cluster precursor that can be quickly transferred to the hydrogenase enzyme to affect activation. HydA activity is observed to be dependent on the protein fraction containing all three accessory proteins expressed in concert and cannot be accomplished with addition of heat-treated extract or extract filtrate, suggesting that the activation of the hydrogenase structural protein is mediated by interaction with the accessory assembly protein(s). These results represent the first important step in understanding the process of H-cluster assembly and provide significant insights into hydrogenase maturation.
McGlynn
Shawn E
SE
Department of Chemistry and Biochemistry, Montana State University Bozeman, Bozeman, MT 59717, USA.
Ruebush
Shane S
SS
Naumov
Anatoli
A
Nagy
Lauren E
LE
Dubini
Alexandra
A
King
Paul W
PW
Broderick
Joan B
JB
Posewitz
Matthew C
MC
Peters
John W
JW
D002457:Cell Extracts; D003013:Clostridium / Q000201:enzymology / Q000235:genetics; D004789:Enzyme Activation; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D006859:Hydrogen / Q000378:metabolism; D006864:Hydrogenase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D007506:Iron-Sulfur Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D011485:Protein Binding; D017434:Protein Structure, Tertiary
D002457:Cell Extracts; D007506:Iron-Sulfur Proteins; D006859:Hydrogen; C118830:iron hydrogenase; D006864:Hydrogenase