Two-step dimerization for autoproteolysis to activate glycosylasparaginase
Glycosylasparaginase (GA) is an amidase and belongs to a novel family of N-terminal nucleophile hydrolases that use a similar autoproteolytic processing mechanism to generate a mature/active enzyme from a single chain protein precursor. From bacteria to eukaryotes, GAs are conserved in primary sequences, tertiary structures, and activation of amidase activity by intramolecular autoproteolysis. An evolutionarily conserved His-Asp-Thr sequence is cleaved to generate a newly exposed N-terminal threonine, which plays a central role in both autoproteolysis and in its amidase activity. We have recently determined the crystal structure of the bacterial GA precursor at 1.9-A resolution, which reveals a highly distorted and energetically unfavorable conformation at the scissile peptide bond. A mechanism of autoproteolysis via an N-O acyl shift was proposed to relieve these conformational strains. However, it is not understood how the polypeptide chain distortion was generated and preserved during the folding of GA to trigger autoproteolysis. An obstacle to our understanding of GA autoproteolysis is the uncertainty concerning its quaternary structure in solution. Here we have revisited this question and show that GA forms dimers in solution. Mutants with alterations at the dimer interface cannot form dimers and are impaired in the autoproteolytic activation. This suggests that dimerization of GA plays an essential role in autoproteolysis to activate the amidase activity. Comparison of the melting temperatures of GA dimers before and after autoproteolysis suggests two states of dimerization in the process of enzyme maturation. A two-step dimerization mechanism to trigger autoproteolysis is proposed to accommodate the data presented here as well as those in the literature.
Medienart: |
Artikel |
---|
Erscheinungsjahr: |
2003 |
---|---|
Erschienen: |
2003 |
Enthalten in: |
Zur Gesamtaufnahme - volume:278 |
---|---|
Enthalten in: |
The Journal of biological chemistry - 278(2003), 5 vom: 31. Jan., Seite 3210-9 |
Sprache: |
Englisch |
---|
Beteiligte Personen: |
Wang, Yeming [VerfasserIn] |
---|
Themen: |
Aspartylglucosylaminase |
---|
Anmerkungen: |
Date Completed 03.04.2003 Date Revised 06.02.2021 published: Print-Electronic Citation Status MEDLINE |
---|
Förderinstitution / Projekttitel: |
|
---|
PPN (Katalog-ID): |
NLM122204522 |
---|
LEADER | 01000naa a22002652 4500 | ||
---|---|---|---|
001 | NLM122204522 | ||
003 | DE-627 | ||
005 | 20231222194717.0 | ||
007 | tu | ||
008 | 231222s2003 xx ||||| 00| ||eng c | ||
028 | 5 | 2 | |a pubmed24n0408.xml |
035 | |a (DE-627)NLM122204522 | ||
035 | |a (NLM)12433919 | ||
040 | |a DE-627 |b ger |c DE-627 |e rakwb | ||
041 | |a eng | ||
100 | 1 | |a Wang, Yeming |e verfasserin |4 aut | |
245 | 1 | 0 | |a Two-step dimerization for autoproteolysis to activate glycosylasparaginase |
264 | 1 | |c 2003 | |
336 | |a Text |b txt |2 rdacontent | ||
337 | |a ohne Hilfsmittel zu benutzen |b n |2 rdamedia | ||
338 | |a Band |b nc |2 rdacarrier | ||
500 | |a Date Completed 03.04.2003 | ||
500 | |a Date Revised 06.02.2021 | ||
500 | |a published: Print-Electronic | ||
500 | |a Citation Status MEDLINE | ||
520 | |a Glycosylasparaginase (GA) is an amidase and belongs to a novel family of N-terminal nucleophile hydrolases that use a similar autoproteolytic processing mechanism to generate a mature/active enzyme from a single chain protein precursor. From bacteria to eukaryotes, GAs are conserved in primary sequences, tertiary structures, and activation of amidase activity by intramolecular autoproteolysis. An evolutionarily conserved His-Asp-Thr sequence is cleaved to generate a newly exposed N-terminal threonine, which plays a central role in both autoproteolysis and in its amidase activity. We have recently determined the crystal structure of the bacterial GA precursor at 1.9-A resolution, which reveals a highly distorted and energetically unfavorable conformation at the scissile peptide bond. A mechanism of autoproteolysis via an N-O acyl shift was proposed to relieve these conformational strains. However, it is not understood how the polypeptide chain distortion was generated and preserved during the folding of GA to trigger autoproteolysis. An obstacle to our understanding of GA autoproteolysis is the uncertainty concerning its quaternary structure in solution. Here we have revisited this question and show that GA forms dimers in solution. Mutants with alterations at the dimer interface cannot form dimers and are impaired in the autoproteolytic activation. This suggests that dimerization of GA plays an essential role in autoproteolysis to activate the amidase activity. Comparison of the melting temperatures of GA dimers before and after autoproteolysis suggests two states of dimerization in the process of enzyme maturation. A two-step dimerization mechanism to trigger autoproteolysis is proposed to accommodate the data presented here as well as those in the literature | ||
650 | 4 | |a Journal Article | |
650 | 4 | |a Research Support, U.S. Gov't, P.H.S. | |
650 | 7 | |a Cross-Linking Reagents |2 NLM | |
650 | 7 | |a Enzyme Precursors |2 NLM | |
650 | 7 | |a Aspartylglucosylaminase |2 NLM | |
650 | 7 | |a EC 3.5.1.26 |2 NLM | |
650 | 7 | |a Glutaral |2 NLM | |
650 | 7 | |a T3C89M417N |2 NLM | |
700 | 1 | |a Guo, Hwai-Chen |e verfasserin |4 aut | |
773 | 0 | 8 | |i Enthalten in |t The Journal of biological chemistry |d 1945 |g 278(2003), 5 vom: 31. Jan., Seite 3210-9 |w (DE-627)NLM000004995 |x 1083-351X |7 nnns |
773 | 1 | 8 | |g volume:278 |g year:2003 |g number:5 |g day:31 |g month:01 |g pages:3210-9 |
912 | |a GBV_USEFLAG_A | ||
912 | |a GBV_NLM | ||
951 | |a AR | ||
952 | |d 278 |j 2003 |e 5 |b 31 |c 01 |h 3210-9 |