Activating Compound | Comment | Organism | Structure |
---|---|---|---|
dithiothreitol | activity is strongly dependent on the presence of dithiothreitol, with activity increasing up to 46% when the reductant is present in the reaction mixture. Concentrations higher than 5 mM cause an inhibitory effect | Haloferax volcanii |
Cloned (Comment) | Organism |
---|---|
expression in Escherichia coli | Haloferax volcanii |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
dithiothreitol | activity is strongly dependent on the presence of dithiothreitol, with activity increasing up to 46% when the reductant is present in the reaction mixture. Concentrations higher than 5 mM cause an inhibitory effect | Haloferax volcanii | |
L-cysteine | above 0.5 mM | Haloferax volcanii |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
KCl | 0-0.5 M KCl gives optimal activities at around 55-60°C. When the KCl concentration is increased to 2.5-3 M, this optimum temperature shifts to between 70-75°C | Haloferax volcanii |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
46800 | - |
2 * 46800, calculated from sequence | Haloferax volcanii |
60200 | - |
2 * 60200, SDS-PAGE | Haloferax volcanii |
110000 | - |
gel filtration | Haloferax volcanii |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
additional information | Haloferax volcanii | the enzyme is involved in Fe-S cluster assembly in haloarchaea | ? | - |
? | |
additional information | Haloferax volcanii DSM 3757 | the enzyme is involved in Fe-S cluster assembly in haloarchaea | ? | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Haloferax volcanii | D4GYV5 | - |
- |
Haloferax volcanii DSM 3757 | D4GYV5 | - |
- |
Purification (Comment) | Organism |
---|---|
- |
Haloferax volcanii |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
L-cysteine + acceptor | overall reaction, the enzyme shows a selenocysteine lyase activity approximately 280fold higher than its cysteine desulfurase activity. The desulfuration mechanism proposed for this enzyme seems to involve three different stages. At the beginning of the reaction, L-cysteine is quickly bound by the cofactor pyridoxal 5'-phosphate, shifting the UV-VIS spectrum of the enzyme. In this aldimine state, the L-cysteine sulfur atom is attacked by Cys384, resulting in persulfide formation. To regenerate the enzyme, this persulfide state must be resolved by transferring the sulphide to inorganic or organic acceptor molecules (accessory proteins, DTT or to other L-cysteine molecules) | Haloferax volcanii | L-alanine + sulfide + ? | - |
? | |
L-cysteine + acceptor | overall reaction, the enzyme shows a selenocysteine lyase activity approximately 280fold higher than its cysteine desulfurase activity. The desulfuration mechanism proposed for this enzyme seems to involve three different stages. At the beginning of the reaction, L-cysteine is quickly bound by the cofactor pyridoxal 5'-phosphate, shifting the UV-VIS spectrum of the enzyme. In this aldimine state, the L-cysteine sulfur atom is attacked by Cys384, resulting in persulfide formation. To regenerate the enzyme, this persulfide state must be resolved by transferring the sulphide to inorganic or organic acceptor molecules (accessory proteins, DTT or to other L-cysteine molecules) | Haloferax volcanii DSM 3757 | L-alanine + sulfide + ? | - |
? | |
additional information | the enzyme is involved in Fe-S cluster assembly in haloarchaea | Haloferax volcanii | ? | - |
? | |
additional information | the enzyme is involved in Fe-S cluster assembly in haloarchaea | Haloferax volcanii DSM 3757 | ? | - |
? |
Subunits | Comment | Organism |
---|---|---|
dimer | 2 * 60200, SDS-PAGE | Haloferax volcanii |
dimer | 2 * 46800, calculated from sequence | Haloferax volcanii |
Synonyms | Comment | Organism |
---|---|---|
SufS | - |
Haloferax volcanii |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
55 | 60 | 0-0.5 M KCl gives optimal activities at around 55-60°C.When the KCl concentration is increased to 2.5-3 M, this optimum temperature shifts to between 70-75°C | Haloferax volcanii |
65 | - |
assay at | Haloferax volcanii |
70 | 75 | 0-0.5 M KCl gives optimal activities at around 55-60°C.When the KCl concentration is increased to 2.5-3 M, this optimum temperature shifts to between 70-75°C | Haloferax volcanii |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.5 | - |
maximal activity is obtained in 50 mM phosphate buffer, pH7.5, 2 M KCl at 65°C | Haloferax volcanii |
pH Minimum | pH Maximum | Comment | Organism |
---|---|---|---|
6.5 | 10 | pH 6.5: about 45% of maximal activity, pH 10.0: about 45% of maximal activity | Haloferax volcanii |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
pyridoxal 5'-phosphate | - |
Haloferax volcanii |
General Information | Comment | Organism |
---|---|---|
physiological function | the enzyme is involved in Fe-S cluster assembly in haloarchaea | Haloferax volcanii |