Any feedback?
Please rate this page
(all_enzymes.php)
(0/150)

BRENDA support

6.3.4.4: adenylosuccinate synthase

This is an abbreviated version!
For detailed information about adenylosuccinate synthase, go to the full flat file.

Word Map on EC 6.3.4.4

Reaction

GTP
+
IMP
 +
L-aspartate
=
GDP
 +
phosphate
 +
N6-(1,2-dicarboxyethyl)-AMP

Synonyms

adenosylsuccinate synthase, adenosylsuccinate synthetase, adenylo-succinate synthetase, Adenylosuccinate synthase, Adenylosuccinate synthetase, adenylosuccinate synthetase 1, AdSS, AdSS1, AdSS2, AdSSL1, AMPSase, AMPsS, Arabdss, AS-synthetase, ASS, IMP--aspartate ligase, IMP-aspartate ligase, mouse muscle synthetase, PfAdSS, purA, Succino-AMP synthetase, Succinoadenylic kinosynthetase, Wheatadss

ECTree

     6 Ligases
         6.3 Forming carbon-nitrogen bonds
             6.3.4 Other carbon-nitrogen ligases
                6.3.4.4 adenylosuccinate synthase

Engineering

Engineering on EC 6.3.4.4 - adenylosuccinate synthase

Please wait a moment until all data is loaded. This message will disappear when all data is loaded.
PROTEIN VARIANTS
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
P242N
D13A
-
mutant enzyme D13A shows no measurable activity, mutant enzymes E14A and H41N exhibit 1% of the activity of the wild-type enzyme and 2-7fold increases in Km of substrates. The mutant enzyme K16Q has 34% of the activity of wild-type enzyme and Km values for substrates are virtually unchanged from those of the wild-type enzyme
D21A
-
directed mutagenesis
D231A
-
wild-type and mutant enzymes, R132K, R143L, and D231A exist as a mixture of monomers and dimers, with a majority of the enzyme in the monomeric state. In the presence of active site ligands, the wild-type enzyme exists almost exclusively as a dimer, whereas the mutant enzymes show only slightly decreased dissociation constants for the dimerization
D333E
-
mutant enzymes D333N, D333E, and D333Q show decreased turnover numbers and increased Km values for GTP. The three mutants each have higher affinity for XTP and ITP than does the wild-type enzyme
D333N
-
mutant enzymes D333N, D333E, and D333Q show decreased turnover numbers and increased Km values for GTP. The three mutants each have higher affinity for XTP and ITP than does the wild-type enzyme
D333Q
-
mutant enzymes D333N, D333E, and D333Q show decreased turnover numbers and increased Km values for GTP. The three mutants each have higher affinity for XTP and ITP than does the wild-type enzyme
E14A
-
mutant enzyme D13A shows no measurable activity, mutant enzymes E14A and H41N exhibit 1% of the activity of the wild-type enzyme and 2-7fold increases in Km of substrates. The mutant enzyme K16Q has 34% of the activity of wild-type enzyme and Km values for substrates are virtually unchanged from those of the wild-type enzyme
G12V
-
replacement of Gly12, Gly15, or Gly17 with Val, or replacement of Lys18 with Arg, results in significant decrease in the kcat/Km values of the enzyme
G15V
-
the secondary structure of the G15V mutant is significantly altered by GTP and IMP, whereas that of the wild-type enzyme is not changed, however the two enzymes exhibit similar secondary structures in the absence of substrates. K331L mutant enzyme shows a 27fold increased Km for GTP, and the K331R mutant a 20fold increased Km for GTP
G17V
-
replacement of Gly12, Gly15, or Gly17 with Val, or replacement of Lys18 with Arg, results in significant decrease in the kcat/Km values of the enzyme
K16Q
-
site-directed mutagenesis
K331l
-
the secondary structure of the G15V mutant is significantly altered by GTP and IMP, whereas that of the wild-type enzyme is not changed, however the two enzymes exhibit similar secondary structures in the absence of substrates. K331L mutant enzyme shows a 27fold increased Km for GTP, and the K331R mutant a 20fold increased Km for GTP
K331R
-
the secondary structure of the G15V mutant is significantly altered by GTP and IMP, whereas that of the wild-type enzyme is not changed, however the two enzymes exhibit similar secondary structures in the absence of substrates. K331L mutant enzyme shows a 27fold increased Km for GTP, and the K331R mutant a 20fold increased Km for GTP
L18R
-
replacement of Gly12, Gly15, or Gly17 with Val, or replacement of Lys18 with Arg, results in significant decrease in the kcat/Km values of the enzyme
L228A
-
mutant enzymes L228A and S240A exhibit modest changes in their initial rate kinetics relative to the wild-type enzyme. The mutant enzymes Q224M and Q224E exhibit no significant change in Km values for GTP and Asp and modest change in Km values for IMP relative to the wild-type enzyme. The mutant Q224E shows an optimum pH at 6.2, which is 1.5 units lower than that of the wild-type enzyme. Mutant Q34E exhibits a 60fold decrease in turnover number compared with that of the wild-type enzyme
N38D
-
directed mutagenesis
N38E
-
directed mutagenesis
Q224M
-
mutant enzymes L228A and S240A exhibit modest changes in their initial rate kinetics relative to the wild-type enzyme. The mutant enzymes Q224M and Q224E exhibit no significant change in Km values for GTP and Asp and modest change in Km values for IMP relative to the wild-type enzyme. The mutant Q224E shows an optimum pH at 6.2, which is 1.5 units lower than that of the wild-type enzyme. Mutant Q34E exhibits a 60fold decrease in turnover number compared with that of the wild-type enzyme
Q34E
-
mutant enzymes L228A and S240A exhibit modest changes in their initial rate kinetics relative to the wild-type enzyme. The mutant enzymes Q224M and Q224E exhibit no significant change in Km values for GTP and Asp and modest change in Km values for IMP relative to the wild-type enzyme. The mutant Q224E shows an optimum pH at 6.2, which is 1.5 units lower than that of the wild-type enzyme. Mutant Q34E exhibits a 60fold decrease in turnover number compared with that of the wild-type enzyme
R132L
-
wild-type and mutant enzymes, R132K, R143L, and D231A exist as a mixture of monomers and dimers, with a majority of the enzyme in the monomeric state. In the presence of active site ligands, the wild-type enzyme exists almost exclusively as a dimer, whereas the mutant enzymes show only slightly decreased dissociation constants for the dimerization
R143K
-
site-directed mutagenesis
R143L
R147L
-
mutant R147L shows increased Km for IMP and GTP relative to the wild-type enzyme, Km for Asp exhibits a modest decrease
R303L
R304L
R305L
R419L
-
directed mutagenesis
S240A
-
mutant enzymes L228A and S240A exhibit modest changes in their initial rate kinetics relative to the wild-type enzyme. The mutant enzymes Q224M and Q224E exhibit no significant change in Km values for GTP and Asp and modest change in Km values for IMP relative to the wild-type enzyme. The mutant Q224E shows an optimum pH at 6.2, which is 1.5 units lower than that of the wild-type enzyme. Mutant Q34E exhibits a 60fold decrease in turnover number compared with that of the wild-type enzyme
S240E
-
mutant enzymes L228A and S240A exhibit modest changes in their initial rate kinetics relative to the wild-type enzyme. The mutant enzymes Q224M and Q224E exhibit no significant change in Km values for GTP and Asp and modest change in Km values for IMP relative to the wild-type enzyme. The mutant Q224E shows an optimum pH at 6.2, which is 1.5 units lower than that of the wild-type enzyme. Mutant Q34E exhibits a 60fold decrease in turnover number compared with that of the wild-type enzyme
T128A
site-directed mutagenesis
T129A
site-directed mutagenesis
T300A
site-directed mutagenesis
T301A
site-directed mutagenesis
T42A
-
directed mutagenesis
V273A
site-directed mutagenesis
V273N
site-directed mutagenesis
V273T
site-directed mutagenesis
C328D
the mutant shows reduced Km and increased turnover number for L-aspartate compared to the wild type protein
C328D/C368D
the mutant shows reduced Km and turnover number for L-aspartate compared to the wild type protein
C328S
the mutant exhibits no change in the aspartate Km value but reduced turnover number compared to the wild type protein
C328S/C368S
the mutant shows a 4fold reduced Km for aspartate and reduced turnover number compared to the wild type protein
C368S
the mutant exhibits a 1.7fold increase in the aspartate Km value compared to the wild type protein
K62L
increase in Km values for IMP, GTP and aspartate, respectively
N429V
increase in Km values for IMP, GTP and aspartate, respectively, along with a 5 fold drop in the kcat value
R155A
residue influences both ligand binding and catalysis
R155A/G146R
unlike dimeric wild-type, mainly monomeric. Inactive
R155K
residue influences both ligand binding and catalysis
R155L
residue influences both ligand binding and catalysis
T307V
increase in Km values for IMP, GTP and aspartate, respectively
additional information
-
the activity of AMPsS in crude dialyzed cell extracts is 2times lower in the guaBDELTACBS mutant compared with the wild type strain