Literature summary extracted from

  • Schmitz, O.; Boison, G.; Salzmann, H.; Bothe, H.; Schutz, K.; Wang, S.H.; Happe, T.
    HoxE - a subunit specific for the pentameric bidirectional hydrogenase complex (HoxEFUYH) of cyanobacteria (2002), Biochim. Biophys. Acta, 1554, 66-74.
    View publication on PubMed

Cloned(Commentary)

EC Number Cloned (Comment) Organism
1.12.1.2 overexpression of HoxE in Escherichia coli strain M15 Synechocystis sp.

KM Value [mM]

EC Number KM Value [mM] KM Value Maximum [mM] Substrate Comment Organism Structure
1.12.1.2 0.089
-
reduced methyl viologen pH 6.3, 60°C Synechocystis sp.

Metals/Ions

EC Number Metals/Ions Comment Organism Structure
1.12.1.2 additional information metalloenzyme Synechocystis sp.

Molecular Weight [Da]

EC Number Molecular Weight [Da] Molecular Weight Maximum [Da] Comment Organism
1.12.1.2 18000
-
x * 18000, HoxE, SDS-PAGE, x * 21000, recombinant HIs-tagged HoxE, SDS-PAGE Synechocystis sp.
1.12.1.2 21000
-
x * 18000, HoxE, SDS-PAGE, x * 21000, recombinant HIs-tagged HoxE, SDS-PAGE Synechocystis sp.
1.12.1.2 375000
-
native dimeric assembly of the pentameric enzyme complex, gel filtration Synechocystis sp.

Natural Substrates/ Products (Substrates)

EC Number Natural Substrates Organism Comment (Nat. Sub.) Natural Products Comment (Nat. Pro.) Rev. Reac.
1.12.1.2 H2 + NAD+ Synechocystis sp.
-
H+ + NADH
-
r

Organism

EC Number Organism UniProt Comment Textmining
1.12.1.2 Synechocystis sp. Q9Z354 HoxE subunit from strain PCC 6301; strain PCC 6803, and strain PCC 6301 which is identical with Anacystis nidulans SAUG 1402-1
-

Oxidation Stability

EC Number Oxidation Stability Organism
1.12.1.2 enzyme is oxygen-labile Synechocystis sp.

Purification (Commentary)

EC Number Purification (Comment) Organism
1.12.1.2 under anaerobic conditions, pentameric bidirectional hydrogenase complex HoxEFUYH to near homogeneity 647fold from strain PCC 6803 and 1290fold from strain PCC 6301, recombinant His-tagged HoxE from Escherichia coli Synechocystis sp.

Specific Activity [micromol/min/mg]

EC Number Specific Activity Minimum [µmol/min/mg] Specific Activity Maximum [µmol/min/mg] Comment Organism
1.12.1.2 15
-
native purified enzyme complex from strain PCC 6301, hydrogen-forming activity, cofactor reduced methyl viologen Synechocystis sp.
1.12.1.2 67
-
native purified enzyme complex from strain PCC 6803, hydrogen-forming activity, cofactor reduced methyl viologen Synechocystis sp.

Substrates and Products (Substrate)

EC Number Substrates Comment Substrates Organism Products Comment (Products) Rev. Reac.
1.12.1.2 H2 + NAD(P)+
-
Synechocystis sp. H+ + NAD(P)H
-
r
1.12.1.2 H2 + NAD+
-
Synechocystis sp. H+ + NADH
-
r
1.12.1.2 H2 + oxidized dithionite
-
Synechocystis sp. H+ + reduced dithionite
-
r
1.12.1.2 H2 + oxidized methyl viologen
-
Synechocystis sp. H+ + reduced methyl viologen best cofactor r

Subunits

EC Number Subunits Comment Organism
1.12.1.2 ? x * 18000, HoxE, SDS-PAGE, x * 21000, recombinant HIs-tagged HoxE, SDS-PAGE Synechocystis sp.
1.12.1.2 More the subunit HoxE, which is essential for the bidirectional hydrogenase activity, is included in a pentameric bidirectional hydrogenase complex HoxEFUYH in cyanobacteria, the complex forms dimer (HoxEFUYH)2, complex components are HoxE, HoxF, HoxH, HoxU, and HoxY, complex composition analysis, overview Synechocystis sp.

Synonyms

EC Number Synonyms Comment Organism
1.12.1.2 HoxE
-
Synechocystis sp.

Temperature Optimum [°C]

EC Number Temperature Optimum [°C] Temperature Optimum Maximum [°C] Comment Organism
1.12.1.2 60
-
strain PCC 6803, hydrogen-forming activity Synechocystis sp.

Temperature Stability [°C]

EC Number Temperature Stability Minimum [°C] Temperature Stability Maximum [°C] Comment Organism
1.12.1.2 75
-
inactivation above Synechocystis sp.

pH Optimum

EC Number pH Optimum Minimum pH Optimum Maximum Comment Organism
1.12.1.2 6.3
-
strain PCC 6803, hydrogen-forming activity Synechocystis sp.

Cofactor

EC Number Cofactor Comment Organism Structure
1.12.1.2 NAD(P)+
-
Synechocystis sp.
1.12.1.2 additional information methyl viologen or dithionite can act as electron donor/acceptor Synechocystis sp.
1.12.1.2 NAD(P)H NADH is 2times more active than NADPH Synechocystis sp.
1.12.1.2 additional information no activity with ferredoxin or FMN Synechocystis sp.