Activating Compound | Comment | Organism | Structure |
---|---|---|---|
2-mercaptoethanol | 2-mercaptoethanol or thiols like such as dithiothreitol are required for the isomerization reaction of the lyase: without, only the phycocyanobilin addition product is formed, but no [phycoerythrocyanin alpha-subunit]-Cys84-phycoviolobilin. Too much 2-mercaptoethanol will cause the loss of chromophore, in a reaction requiring oxygen. When Mg2+ is used as the activator, the optimal concentration of 2-mercaptoethanol is 5 mM, with Mn2+ it is 3 mM | Mastigocladus laminosus | |
dithiothreitol | 2-mercaptoethanol or thiols like such as dithiothreitol are required for the isomerization reaction of the lyase: without, only the phycocyanobilin addition product is formed, but no [phycoerythrocyanin alpha-subunit]-Cys84-phycoviolobilin | Mastigocladus laminosus |
Cloned (Comment) | Organism |
---|---|
- |
Mastigocladus laminosus |
General Stability | Organism |
---|---|
denaturation in 8 M urea of the individual subunits, PecE or PecF, is largely irreversible. If they are mixed together after dialysing out the urea separately, they show only little activity | Mastigocladus laminosus |
repetitive freezing and thawing should be avoided, as it causes the purified proteins to precipitate | Mastigocladus laminosus |
very stable preparations are obtained by adding an equal volume of glycerol before freezing | Mastigocladus laminosus |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
Co2+ | 5 mM, complete inhibition | Mastigocladus laminosus | |
Cu2+ | 5 mM, complete inhibition | Mastigocladus laminosus | |
Fe2+ | 5 mM, complete inhibition | Mastigocladus laminosus | |
Mg2+ | 25 mM, 38% inhibition | Mastigocladus laminosus | |
Mn2+ | 25 mM, complete inhibition | Mastigocladus laminosus | |
Ni2+ | 5 mM, complete inhibition | Mastigocladus laminosus | |
potassium phosphate | the buffer decreases the effect of the activators, Mn2+ or Mg2+, by 20% as compared with Tris/HCl buffer | Mastigocladus laminosus | |
Zn2+ | 5 mM, complete inhibition | Mastigocladus laminosus |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.0024 | - |
apo-[phycoerythrocyanin alpha-subunit] | at 0.014 mM (2R,3E)-phycocyanobilin, pH and temperature not specified in the publication | Mastigocladus laminosus | |
0.012 | 0.016 | (2R,3E)-phycocyanobilin | depending on apo-[phycoerythrocyanin alpha-subunit] (0.0048-0.019 mM), pH and temperature not specified in the publication | Mastigocladus laminosus |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Ca2+ | less effective in activation (at 5 mM) than Mg2+ or Mn2+ | Mastigocladus laminosus | |
Mg2+ | the enzyme requires Mg2+ or Mn2+, optimum concentration of Mg2+ is 5 mM | Mastigocladus laminosus | |
Mn2+ | the enzyme requires Mg2+ or Mn2+, optimum concentration of Mn2+ is 3 mM | Mastigocladus laminosus |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
apo-[phycoerythrocyanin alpha-subunit] + (2R,3E)-phycocyanobilin | Mastigocladus laminosus | the enzyme catalyses the covalent attachment of the phycobilin chromophore phycocyanobilin to cysteine 84 of the beta subunit of the phycobiliprotein phycoerythrocyanin and its isomerization to phycoviolobilin | [phycoerythrocyanin alpha-subunit]-Cys84-phycoviolobilin | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Mastigocladus laminosus | P29729 and P29730 | P29729: bilin biosynthesis protein PecE, P29730: bilin biosynthesis protein PecF | - |
Purification (Comment) | Organism |
---|---|
His-tagged PecE and PecF | Mastigocladus laminosus |
Storage Stability | Organism |
---|---|
-20°C, 1 year, His-tagged PecE and PecF are stable | Mastigocladus laminosus |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
apo-[phycoerythrocyanin alpha-subunit] + (2R,3E)-phycocyanobilin | the enzyme catalyses the covalent attachment of the phycobilin chromophore phycocyanobilin to cysteine 84 of the beta subunit of the phycobiliprotein phycoerythrocyanin and its isomerization to phycoviolobilin | Mastigocladus laminosus | [phycoerythrocyanin alpha-subunit]-Cys84-phycoviolobilin | - |
? |
Subunits | Comment | Organism |
---|---|---|
? | formation of complexes between the subunits, PecE and PecF | Mastigocladus laminosus |
Synonyms | Comment | Organism |
---|---|---|
phycoviolobilin phycoerythrocyanin-alpha84-cystein-lyase | - |
Mastigocladus laminosus |
PVBPEC-lyase | - |
Mastigocladus laminosus |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
22 | - |
room temperature is recommended in the absence of Triton X-100, because the proteins tend to precipitate at 37°C. In the presence of Triton X-100 (1% v/v) the temperature can be increased without precipitation to 37°C (Mg2+ as activator), or even to 45°C (Mn2+ as activator) | Mastigocladus laminosus |
37 | - |
room temperature is recommended in the absence of Triton X-100, because the proteins tend to precipitate at 37°C. In the presence of Triton X-100 (1% v/v) the temperature can be increased without precipitation to 37°C with Mg2+ as activator | Mastigocladus laminosus |
45 | - |
room temperature is recommended in the absence of Triton X-100, because the proteins tend to precipitate at 37°C. In the presence of Triton X-100 (1% v/v) the temperature can be increased without precipitation to 45°C with Mn2+ as activator | Mastigocladus laminosus |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.00001 | 0.00013 | apo-[phycoerythrocyanin alpha-subunit] | depending on apo phycoerythrocyanin alpha-subunit (0.0048-0.019 mM), pH and temperature not specified in the publication | Mastigocladus laminosus | |
0.000074 | - |
(2R,3E)-phycocyanobilin | at 0.014 mM apo phycoerythrocyanin alpha-subunit, pH and temperature not specified in the publication | Mastigocladus laminosus |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.5 | 7.8 | - |
Mastigocladus laminosus |
pH Minimum | pH Maximum | Comment | Organism |
---|---|---|---|
7 | 8.5 | pH 7.0: about 40% of maximal activity, pH 8.5: about 60% of maximal activity | Mastigocladus laminosus |