Generalized enzymatic mechanism of catalysis by tetrameric L-asparaginases from mesophilic bacteria.
Generalized enzymatic mechanism of catalysis by tetrameric L-asparaginases from mesophilic bacteria.
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DOI：
10.1038/s41598-020-74480-4
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发表时间：
2020-10-15
影响因子：
4.6
通讯作者：
Lubkowski J
中科院分区：
文献类型：
--
作者：
Strzelczyk P;Zhang D;Dyba M;Wlodawer A;Lubkowski J
The mechanism of catalysis by the l-glutaminase-asparaginase from Pseudomonas 7A (PGA) was investigated using structural, mass spectrometry, and kinetic data. We had previously proposed mechanism of hydrolysis of l-Asn by the type II l-asparaginase from E. coli (EcAII), but that work was limited to just one enzyme. Based on results presented in this report, we postulate that all homotetrameric l-asparaginases from mesophilic bacteria utilize a common ping-pong mechanism of catalysis consisting of two subsequent nucleophilic substitutions. Several new structures of non-covalent complexes of PGA with different substrates, as well as structures of covalent acyl-enzyme intermediates of PGA with canonical substrates (l-Asp and l-Glu) and an opportunistic ligand, a citrate anion, were determined. The results of kinetic experiments monitored by high-resolution LC/MS, when combined with new structural data, clearly show that the reaction catalyzed by l-glutaminase-asparaginases proceeds through formation of a covalent intermediate, as observed previously for EcAII. Additionally, by showing that the same mechanism applies to l-Asn and l-Gln, we postulate that it is common for all these structurally related enzymes.
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DOI：
10.1107/s0907444904019158
发表时间：
2004-12-01
影响因子：
2.2
作者：
Emsley, P;Cowtan, K
通讯作者：
Cowtan, K
影响因子：
2.9
作者：
Aghaiypour, K;Wlodawer, A;Lubkowski, J
通讯作者：
Lubkowski, J
影响因子：
7.4
作者：
FREAR, DS;BURRELL, RC
通讯作者：
BURRELL, RC
影响因子：
4.6
作者：
Hien Anh Nguyen;Durden, Donald L.;Lavie, Arnon
通讯作者：
Lavie, Arnon
DOI：
10.1107/s0907444909042073
发表时间：
2010-01
期刊：
Acta crystallographica. Section D, Biological crystallography
影响因子：
--
作者：
Chen VB;Arendall WB 3rd;Headd JJ;Keedy DA;Immormino RM;Kapral GJ;Murray LW;Richardson JS;Richardson DC
通讯作者：
Richardson DC