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

BRENDA support

Literature summary for 3.5.1.26 extracted from

  • Pande, S.; Guo, H.C.
    The T99K variant of glycosylasparaginase shows a new structural mechanism of the genetic disease aspartylglucosaminuria (2019), Protein Sci., 28, 1013-1023 .
    View publication on PubMedView publication on EuropePMC
Search for more literature for 3.5.1.26

Crystallization (Commentary)

Crystallization (Comment) Organism
purified recombinant enzyme mutant T99K free and in complex with substrate N4-(beta-N-acetylglucosaminyl)-L-asparagine, hanging drop vapor diffusion technique, mixing of 2mg/ml protein solution with reservoir oslution containing 0.2 M NaCl, 0.1 M bis-Tris, pH 6.5, and 25% PEG 3350, cryoprotection in solution containing 100 mM Tris-HCl, pH 8.0, and 20% glycerol, X-ray diffraction structure determination and analysis at 1.5 A resolution, molecular replacement using the structure of the wild-type enzyme (PDB ID 2GAW) as the starting model Homo sapiens

Protein Variants

Protein Variants Comment Organism
G172D naturally occuring mutation in Finnish population causing aspartylglucosaminuria (AGU) Homo sapiens
G203D naturally occuring mutation in US-American population causing aspartylglucosaminuria (AGU) Homo sapiens
G226D naturally occuring mutation in Canadian population causing aspartylglucosaminuria (AGU) Homo sapiens
T122K naturally occuring mutation in Canadian population causing aspartylglucosaminuria (AGU), the mutant lacks the signal peptide Homo sapiens
T203I naturally occuring mutation in Finnish population causing aspartylglucosaminuria (AGU), the mutant lacks the signal peptide Homo sapiens
T234I naturally occuring mutation in US-American population causing aspartylglucosaminuria (AGU), the mutant lacks the signal peptide Homo sapiens
T257I naturally occuring mutation in Canadian population causing aspartylglucosaminuria (AGU), the mutant lacks the signal peptide Homo sapiens
T99K naturally occuring mutation in Finnish population causing aspartylglucosaminuria (AGU), the mutant lacks the signal peptide Homo sapiens
T99K naturally occuring mutation in US-American population causing aspartylglucosaminuria (AGU). This T99K model enzyme still has autoprocessing capacity to generate a mature form, its amidase activity to digest glycoasparagines remains low. A molecular clamp capable of fixing local disorders at the dimer interface might be able to rescue the deficiency of this AGU variant. The mutant lacks the signal peptide, but shows relatively high amidase activity, about 75% compared to wild-type. T99K has its substratebinding site fully opened through autoproteolysis and is ready to accommodate the substrate NAcGlc-Asn Homo sapiens

KM Value [mM]

KM Value [mM] KM Value Maximum [mM] Substrate Comment Organism Structure
0.09
-
 N4-(beta-N-acetylglucosaminyl)-L-asparagine recombinant wild-type enzyme, pH 7.5, 37°C Homo sapiens
0.166
-
 N4-(beta-N-acetylglucosaminyl)-L-asparagine mutant T203I, pH 7.5, 37°C Homo sapiens
0.26
-
 N4-(beta-N-acetylglucosaminyl)-L-asparagine mutant T99K, pH 7.5, 37°C Homo sapiens

Localization

Localization Comment Organism GeneOntology No. Textmining
lysosome
-
 Homo sapiens 5764
-

Natural Substrates/ Products (Substrates)

Natural Substrates Organism Comment (Nat. Sub.) Natural Products Comment (Nat. Pro.) Rev. Reac.
N4-(beta-N-acetylglucosaminyl)-L-asparagine + H2O Homo sapiens
-
 N-acetyl-D-glucosaminylamine + L-aspartate
-
 ?

Organism

Organism UniProt Comment Textmining
Homo sapiens P20933
-
-

Posttranslational Modification

Posttranslational Modification Comment Organism
proteolytic modification the enzyme is synthesized as a single-chain precursor that requires an intramolecular autoprocessing to form a mature amidase Homo sapiens

Substrates and Products (Substrate)

Substrates Comment Substrates Organism Products Comment (Products) Rev. Reac.
aspartic acid beta-(4-nitroanilide) + H2O
-
 Homo sapiens 4-nitroaniline + L-aspartate
-
 ?
N4-(beta-N-acetylglucosaminyl)-L-asparagine + H2O
-
 Homo sapiens N-acetyl-D-glucosaminylamine + L-aspartate
-
 ?

Subunits

Subunits Comment Organism
heterotetramer (alphabeta)2, dimer of dimers Homo sapiens

Synonyms

Synonyms Comment Organism
glycosylasparaginase
-
 Homo sapiens

Temperature Optimum [°C]

Temperature Optimum [°C] Temperature Optimum Maximum [°C] Comment Organism
37
-
 assay at Homo sapiens

Turnover Number [1/s]

Turnover Number Minimum [1/s] Turnover Number Maximum [1/s] Substrate Comment Organism Structure
0.08
-
 N4-(beta-N-acetylglucosaminyl)-L-asparagine mutant T203I, pH 7.5, 37°C Homo sapiens
5.93
-
 N4-(beta-N-acetylglucosaminyl)-L-asparagine mutant T99K, pH 7.5, 37°C Homo sapiens
14.18
-
 N4-(beta-N-acetylglucosaminyl)-L-asparagine recombinant wild-type enzyme, pH 7.5, 37°C Homo sapiens

pH Optimum

pH Optimum Minimum pH Optimum Maximum Comment Organism
7.5
-
 assay at Homo sapiens

General Information

General Information Comment Organism
malfunction aspartylglucosaminuria (AGU) is an inherited disease caused by mutations in a lysosomal amidase called aspartylglucosaminidase (AGA) or glycosylasparaginase. This disorder results in an accumulation of glycoasparagines in the lysosomes of virtually all cell types, with severe clinical symptoms affecting the central nervous system, skeletal abnormalities, and connective tissue lesions. Many AGU mutations remain as dimers but cannot undergo autoproteolysis and thus lack amidase activity for digesting glycoasparagines Homo sapiens
physiological function the enzyme is is involved in protein degradation by catabolizing Asn-linked glycoproteins in lysosomes Homo sapiens

kcat/KM [mM/s]

kcat/KM Value [1/mMs-1] kcat/KM Value Maximum [1/mMs-1] Substrate Comment Organism Structure
0.482
-
 N4-(beta-N-acetylglucosaminyl)-L-asparagine mutant T203I, pH 7.5, 37°C Homo sapiens
22.8
-
 N4-(beta-N-acetylglucosaminyl)-L-asparagine mutant T99K, pH 7.5, 37°C Homo sapiens
157.6
-
 N4-(beta-N-acetylglucosaminyl)-L-asparagine recombinant wild-type enzyme, pH 7.5, 37°C Homo sapiens