Crystallization (Comment) | Organism |
---|---|
V83Gdel84-89 and its complex with alpha,beta--methyleneadenosine triphosphate and 6-hydroxymethyl-7,8-dihydropterin are crystallized at 19°C using the hanging-drop vapor-diffusion technique | Escherichia coli |
Protein Variants | Comment | Organism |
---|---|---|
V83Gdel84-89 | the deletion mutation does not have significant effects on the dissociation constants or the rate constants for the binding of the first substrate MgATP2- or its analogues. The dissociation constant of 6-hydroxymethyl-7,8-dihydropterin for the mutant increases by a factor of about 100, which is due to a large increase in the dissociation rate constant. The deletion mutation causes a shift of the rate-limiting step in the reaction and a decrease in the rate constant for the chemical step by a factor of 110000. The crystal structures reveal that the deletion mutation does not affect protein folding, but the catalytic center of the mutant is not fully assembled even upon the formation of the ternary complex and is not properly sealed. Loop 3 is dispensable for the folding of the protein and the binding of the first substrate MgATP2-, but is required for the assembling and sealing of the active center. The loop plays an important role in the stabilization of the ternary complex and is critical for catalysis | Escherichia coli |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Escherichia coli | P26281 | - |
- |
Purification (Comment) | Organism |
---|---|
HPPK-GST fusion proteins | Escherichia coli |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + 6-hydroxymethyl-7,8-dihydropteridine | ordered bi-bi mechanism with ATP as the first substrate | Escherichia coli | AMP + 6-hydroxymethyl-7,8-dihydropteridine diphosphate | - |
? |
Synonyms | Comment | Organism |
---|---|---|
6-hydroxymethyl-7,8-dihydropterin pyrophosphokinase | - |
Escherichia coli |