Insights into the Mn<sup>2+</sup> Binding Site in the Agmatinase-Like Protein (ALP): A Critical Enzyme for the Regulation of Agmatine Levels in Mammals

Agmatine is a neurotransmitter with anticonvulsant, anti-neurotoxic and antidepressant-like effects, in addition it has hypoglycemic actions. Agmatine is converted to putrescine and urea by agmatinase (AGM) and by an agmatinase-like protein (ALP), a new type of enzyme which is present in human and r...

Full description

Bibliographic Details
Main Authors: María-Belen Reyes, José Martínez-Oyanedel, Camila Navarrete, Erika Mardones, Ignacio Martínez, Mónica Salas, Vasthi López, María García-Robles, Estefania Tarifeño-Saldivia, Maximiliano Figueroa, David García, Elena Uribe
Format: Article
Language:English
Published: MDPI AG 2020-06-01
Series:International Journal of Molecular Sciences
Subjects:
Online Access:https://www.mdpi.com/1422-0067/21/11/4132
_version_ 1797565629253812224
author María-Belen Reyes
José Martínez-Oyanedel
Camila Navarrete
Erika Mardones
Ignacio Martínez
Mónica Salas
Vasthi López
María García-Robles
Estefania Tarifeño-Saldivia
Maximiliano Figueroa
David García
Elena Uribe
author_facet María-Belen Reyes
José Martínez-Oyanedel
Camila Navarrete
Erika Mardones
Ignacio Martínez
Mónica Salas
Vasthi López
María García-Robles
Estefania Tarifeño-Saldivia
Maximiliano Figueroa
David García
Elena Uribe
author_sort María-Belen Reyes
collection DOAJ
description Agmatine is a neurotransmitter with anticonvulsant, anti-neurotoxic and antidepressant-like effects, in addition it has hypoglycemic actions. Agmatine is converted to putrescine and urea by agmatinase (AGM) and by an agmatinase-like protein (ALP), a new type of enzyme which is present in human and rodent brain tissues. Recombinant rat brain ALP is the only mammalian protein that exhibits significant agmatinase activity in vitro and generates putrescine under in vivo conditions. ALP, despite differing in amino acid sequence from all members of the ureohydrolase family, is strictly dependent on Mn<sup>2+</sup> for catalytic activity. However, the Mn<sup>2+</sup> ligands have not yet been identified due to the lack of structural information coupled with the low sequence identity that ALPs display with known ureohydrolases. In this work, we generated a structural model of the Mn<sup>2+</sup> binding site of the ALP and we propose new putative Mn<sup>2+</sup> ligands. Then, we cloned and expressed a sequence of 210 amino acids, here called the “central-ALP”, which include the putative ligands of Mn<sup>2+</sup>. The results suggest that the central-ALP is catalytically active, as agmatinase, with an unaltered <i>K<sub>m</sub></i> for agmatine and a decreased <i>k<sub>cat</sub></i>. Similar to wild-type ALP, central-ALP is activated by Mn<sup>2+</sup> with a similar affinity. Besides, a simple mutant D217A, a double mutant E288A/K290A, and a triple mutant N213A/Q215A/D217A of these putative Mn<sup>2+</sup> ligands result on the loss of ALP agmatinase activity. Our results indicate that the central-ALP contains the active site for agmatine hydrolysis, as well as that the residues identified are relevant for the ALP catalysis.
first_indexed 2024-03-10T19:15:49Z
format Article
id doaj.art-366a301dfd914e6c858982d21598e8a9
institution Directory Open Access Journal
issn 1661-6596
1422-0067
language English
last_indexed 2024-03-10T19:15:49Z
publishDate 2020-06-01
publisher MDPI AG
record_format Article
series International Journal of Molecular Sciences
spelling doaj.art-366a301dfd914e6c858982d21598e8a92023-11-20T03:23:41ZengMDPI AGInternational Journal of Molecular Sciences1661-65961422-00672020-06-012111413210.3390/ijms21114132Insights into the Mn<sup>2+</sup> Binding Site in the Agmatinase-Like Protein (ALP): A Critical Enzyme for the Regulation of Agmatine Levels in MammalsMaría-Belen Reyes0José Martínez-Oyanedel1Camila Navarrete2Erika Mardones3Ignacio Martínez4Mónica Salas5Vasthi López6María García-Robles7Estefania Tarifeño-Saldivia8Maximiliano Figueroa9David García10Elena Uribe11Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4070386, ChileDepartamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4070386, ChileDepartamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4070386, ChileDepartamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4070386, ChileDepartamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4070386, ChileInstituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia 5110566, ChileDepartamento de Ciencias Biomédicas, Universidad Católica del Norte, Coquimbo 1781421, ChileDepartamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 3349001, ChileDepartamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4070386, ChileDepartamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4070386, ChileDepartamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4070386, ChileDepartamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4070386, ChileAgmatine is a neurotransmitter with anticonvulsant, anti-neurotoxic and antidepressant-like effects, in addition it has hypoglycemic actions. Agmatine is converted to putrescine and urea by agmatinase (AGM) and by an agmatinase-like protein (ALP), a new type of enzyme which is present in human and rodent brain tissues. Recombinant rat brain ALP is the only mammalian protein that exhibits significant agmatinase activity in vitro and generates putrescine under in vivo conditions. ALP, despite differing in amino acid sequence from all members of the ureohydrolase family, is strictly dependent on Mn<sup>2+</sup> for catalytic activity. However, the Mn<sup>2+</sup> ligands have not yet been identified due to the lack of structural information coupled with the low sequence identity that ALPs display with known ureohydrolases. In this work, we generated a structural model of the Mn<sup>2+</sup> binding site of the ALP and we propose new putative Mn<sup>2+</sup> ligands. Then, we cloned and expressed a sequence of 210 amino acids, here called the “central-ALP”, which include the putative ligands of Mn<sup>2+</sup>. The results suggest that the central-ALP is catalytically active, as agmatinase, with an unaltered <i>K<sub>m</sub></i> for agmatine and a decreased <i>k<sub>cat</sub></i>. Similar to wild-type ALP, central-ALP is activated by Mn<sup>2+</sup> with a similar affinity. Besides, a simple mutant D217A, a double mutant E288A/K290A, and a triple mutant N213A/Q215A/D217A of these putative Mn<sup>2+</sup> ligands result on the loss of ALP agmatinase activity. Our results indicate that the central-ALP contains the active site for agmatine hydrolysis, as well as that the residues identified are relevant for the ALP catalysis.https://www.mdpi.com/1422-0067/21/11/4132ureohydrolaseALPmanganese
spellingShingle María-Belen Reyes
José Martínez-Oyanedel
Camila Navarrete
Erika Mardones
Ignacio Martínez
Mónica Salas
Vasthi López
María García-Robles
Estefania Tarifeño-Saldivia
Maximiliano Figueroa
David García
Elena Uribe
Insights into the Mn<sup>2+</sup> Binding Site in the Agmatinase-Like Protein (ALP): A Critical Enzyme for the Regulation of Agmatine Levels in Mammals
International Journal of Molecular Sciences
ureohydrolase
ALP
manganese
title Insights into the Mn<sup>2+</sup> Binding Site in the Agmatinase-Like Protein (ALP): A Critical Enzyme for the Regulation of Agmatine Levels in Mammals
title_full Insights into the Mn<sup>2+</sup> Binding Site in the Agmatinase-Like Protein (ALP): A Critical Enzyme for the Regulation of Agmatine Levels in Mammals
title_fullStr Insights into the Mn<sup>2+</sup> Binding Site in the Agmatinase-Like Protein (ALP): A Critical Enzyme for the Regulation of Agmatine Levels in Mammals
title_full_unstemmed Insights into the Mn<sup>2+</sup> Binding Site in the Agmatinase-Like Protein (ALP): A Critical Enzyme for the Regulation of Agmatine Levels in Mammals
title_short Insights into the Mn<sup>2+</sup> Binding Site in the Agmatinase-Like Protein (ALP): A Critical Enzyme for the Regulation of Agmatine Levels in Mammals
title_sort insights into the mn sup 2 sup binding site in the agmatinase like protein alp a critical enzyme for the regulation of agmatine levels in mammals
topic ureohydrolase
ALP
manganese
url https://www.mdpi.com/1422-0067/21/11/4132
work_keys_str_mv AT mariabelenreyes insightsintothemnsup2supbindingsiteintheagmatinaselikeproteinalpacriticalenzymefortheregulationofagmatinelevelsinmammals
AT josemartinezoyanedel insightsintothemnsup2supbindingsiteintheagmatinaselikeproteinalpacriticalenzymefortheregulationofagmatinelevelsinmammals
AT camilanavarrete insightsintothemnsup2supbindingsiteintheagmatinaselikeproteinalpacriticalenzymefortheregulationofagmatinelevelsinmammals
AT erikamardones insightsintothemnsup2supbindingsiteintheagmatinaselikeproteinalpacriticalenzymefortheregulationofagmatinelevelsinmammals
AT ignaciomartinez insightsintothemnsup2supbindingsiteintheagmatinaselikeproteinalpacriticalenzymefortheregulationofagmatinelevelsinmammals
AT monicasalas insightsintothemnsup2supbindingsiteintheagmatinaselikeproteinalpacriticalenzymefortheregulationofagmatinelevelsinmammals
AT vasthilopez insightsintothemnsup2supbindingsiteintheagmatinaselikeproteinalpacriticalenzymefortheregulationofagmatinelevelsinmammals
AT mariagarciarobles insightsintothemnsup2supbindingsiteintheagmatinaselikeproteinalpacriticalenzymefortheregulationofagmatinelevelsinmammals
AT estefaniatarifenosaldivia insightsintothemnsup2supbindingsiteintheagmatinaselikeproteinalpacriticalenzymefortheregulationofagmatinelevelsinmammals
AT maximilianofigueroa insightsintothemnsup2supbindingsiteintheagmatinaselikeproteinalpacriticalenzymefortheregulationofagmatinelevelsinmammals
AT davidgarcia insightsintothemnsup2supbindingsiteintheagmatinaselikeproteinalpacriticalenzymefortheregulationofagmatinelevelsinmammals
AT elenauribe insightsintothemnsup2supbindingsiteintheagmatinaselikeproteinalpacriticalenzymefortheregulationofagmatinelevelsinmammals