Cloned (Comment) | Organism |
---|---|
gene cyrA, DNA and amino acid sequence determination and analysis, phylogenetic analysis, overexpression of N-terminal His6-tagged CyrA in Escherichia coli strain BL21(DE3) | Cylindrospermopsis raciborskii |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
L-ornithine | partial mixed product inhibition, L-ornithine therefore binds to the active site of CyrA at a binding site distinct from the hydroxylamine-binding site | Cylindrospermopsis raciborskii |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | Michaelis-Menten kinetics with non-natural substrate hydroxylamine, kinetic mechanism of CyrA as a hybrid of ping-pong and sequential mechanisms, overview | Cylindrospermopsis raciborskii | |
3.5 | - |
L-arginine | pH 8.5, 30°C | Cylindrospermopsis raciborskii | |
6.9 | - |
glycine | pH 8.5, 30°C | Cylindrospermopsis raciborskii |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
45680 | - |
2 * 45680, native enzyme, sequence calculation, 2 * 50120, His6-tagged enzyme, sequence calculation | Cylindrospermopsis raciborskii |
45680 | - |
4 * 45680, native enzyme, sequence calculation, 4 * 50120, His6-tagged enzyme, sequence calculation | Cylindrospermopsis raciborskii |
50120 | - |
2 * 45680, native enzyme, sequence calculation, 2 * 50120, His6-tagged enzyme, sequence calculation | Cylindrospermopsis raciborskii |
50120 | - |
4 * 45680, native enzyme, sequence calculation, 4 * 50120, His6-tagged enzyme, sequence calculation | Cylindrospermopsis raciborskii |
98000 | - |
dimeric CyrA, gel filtration | Cylindrospermopsis raciborskii |
185000 | - |
tetrameric CyrA, gel filtration | Cylindrospermopsis raciborskii |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
L-arginine + glycine | Cylindrospermopsis raciborskii | - |
L-ornithine + guanidinoacetate | - |
? | |
L-arginine + glycine | Cylindrospermopsis raciborskii AWT205 | - |
L-ornithine + guanidinoacetate | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Cylindrospermopsis raciborskii | B0LI36 | gene cyrA | - |
Cylindrospermopsis raciborskii AWT205 | B0LI36 | gene cyrA | - |
Purification (Comment) | Organism |
---|---|
recombinant N-terminal His6-tagged CyrA from Escherichia coli strain BL21(DE3) | Cylindrospermopsis raciborskii |
Reaction | Comment | Organism | Reaction ID |
---|---|---|---|
L-arginine + glycine = L-ornithine + guanidinoacetate | reaction and kinetic mechanisms, overview | Cylindrospermopsis raciborskii |
Storage Stability | Organism |
---|---|
4°C, purified CyrA, total loss of activity occurs within 48 h despite addition of reducing agents such as dithiothreitol, Tris(2-carboxyethyl) phosphine, or beta-mercaptoethanol | Cylindrospermopsis raciborskii |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
hydroxylamine + glycine | - |
Cylindrospermopsis raciborskii | L-ornithine + hydroxyguanidine | - |
? | |
hydroxylamine + glycine | - |
Cylindrospermopsis raciborskii AWT205 | L-ornithine + hydroxyguanidine | - |
? | |
L-arginine + glycine | - |
Cylindrospermopsis raciborskii | L-ornithine + guanidinoacetate | - |
? | |
L-arginine + glycine | L-ornithine is formed in the presence of only a single substrate, arginine, and its production therefore does not require the presence of the second substrate, glycine | Cylindrospermopsis raciborskii | L-ornithine + guanidinoacetate | - |
? | |
L-arginine + glycine | - |
Cylindrospermopsis raciborskii AWT205 | L-ornithine + guanidinoacetate | - |
? | |
L-arginine + glycine | L-ornithine is formed in the presence of only a single substrate, arginine, and its production therefore does not require the presence of the second substrate, glycine | Cylindrospermopsis raciborskii AWT205 | L-ornithine + guanidinoacetate | - |
? | |
additional information | narrow substrate specificity, no activity with L-homoarginine, agmatine, L-canavanine, guanidine hydrochloride, urea, gamma-guanidinobutyric acid, and beta-guanidinoproprionic acid as amidino group donors, or L-alanine, beta-alanine, gamma-aminobutyric acid, ethanolamine, taurine, L-lysine, alpha-amino-oxyacetic acid and L-norvaline as amidino group acceptors, overview | Cylindrospermopsis raciborskii | ? | - |
? | |
additional information | narrow substrate specificity, no activity with L-homoarginine, agmatine, L-canavanine, guanidine hydrochloride, urea, gamma-guanidinobutyric acid, and beta-guanidinoproprionic acid as amidino group donors, or L-alanine, beta-alanine, gamma-aminobutyric acid, ethanolamine, taurine, L-lysine, alpha-amino-oxyacetic acid and L-norvaline as amidino group acceptors, overview | Cylindrospermopsis raciborskii AWT205 | ? | - |
? |
Subunits | Comment | Organism |
---|---|---|
dimer | 2 * 45680, native enzyme, sequence calculation, 2 * 50120, His6-tagged enzyme, sequence calculation | Cylindrospermopsis raciborskii |
tetramer | 4 * 45680, native enzyme, sequence calculation, 4 * 50120, His6-tagged enzyme, sequence calculation | Cylindrospermopsis raciborskii |
Synonyms | Comment | Organism |
---|---|---|
CyrA | - |
Cylindrospermopsis raciborskii |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
32 | - |
- |
Cylindrospermopsis raciborskii |
Temperature Minimum [°C] | Temperature Maximum [°C] | Comment | Organism |
---|---|---|---|
32 | 40 | 20% of maximal activity at 40°C, maximal activity at 32°C | Cylindrospermopsis raciborskii |
Temperature Stability Minimum [°C] | Temperature Stability Maximum [°C] | Comment | Organism |
---|---|---|---|
additional information | - |
inactive CyrA lacks a well-defined tertiary structure at any temperature | Cylindrospermopsis raciborskii |
44.5 | - |
an inactivated form of this enzyme retains an appreciable amount of secondary structure elements even on heating to 94°C, but loses its tertiary structure at low temperature of 44.5°C resulting in a state reminiscent of a molten globule. The presence of 500 mm NaCl decreases Tmax at pH 7.5 from 54°C to 49°C | Cylindrospermopsis raciborskii |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
875 | - |
glycine | per active site, pH 8.5, 30°C | Cylindrospermopsis raciborskii | |
875 | - |
L-arginine | per active site, pH 8.5, 30°C | Cylindrospermopsis raciborskii |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
8.5 | - |
- |
Cylindrospermopsis raciborskii |
pH Minimum | pH Maximum | Comment | Organism |
---|---|---|---|
7 | 8.5 | 25% of maximal activity at pH 7.0, maximal activity at pH 8.5 | Cylindrospermopsis raciborskii |
pH Stability | pH Stability Maximum | Comment | Organism |
---|---|---|---|
6.5 | - |
purified recombinant enzyme, maximally stable at | Cylindrospermopsis raciborskii |
Ki Value [mM] | Ki Value maximum [mM] | Inhibitor | Comment | Organism | Structure |
---|---|---|---|---|---|
0.25 | - |
L-ornithine | pH 8.5, 30°C | Cylindrospermopsis raciborskii |
Organism | Comment | pI Value Maximum | pI Value |
---|---|---|---|
Cylindrospermopsis raciborskii | sequence calculation, native enzyme | - |
5.1 |
Cylindrospermopsis raciborskii | sequence calculation, His6-tagged enzyme | - |
5.6 |
General Information | Comment | Organism |
---|---|---|
evolution | CyrA is phylogenetically distinct from other amidinotransferases | Cylindrospermopsis raciborskii |
metabolism | CyrA is involved in the pathway for biosynthesis of the polyketide-derived hepatotoxin cylindrospermopsin | Cylindrospermopsis raciborskii |