TY - JOUR
T1 - Glucose-6-phosphate dehydrogenase::6-phosphogluconolactonase from the parasite giardia lamblia. A molecular and biochemical perspective of a fused enzyme
AU - Morales-Luna, Laura
AU - González-Valdez, Abigail
AU - Hernández-Ochoa, Beatriz
AU - Arreguin-Espinosa, Roberto
AU - Ortega-Cuellar, Daniel
AU - Castillo-Rodríguez, Rosa Angélica
AU - Martínez-Rosas, Víctor
AU - Cárdenas-Rodríguez, Noemi
AU - Enríquez-Flores, Sergio
AU - Canseco-ávila, Luis Miguel
AU - Pérez de la Cruz, Verónica
AU - Gómez-Chávez, Fernando
AU - Gómez-Manzo, Saúl
N1 - Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2021/8
Y1 - 2021/8
N2 - Giardia lamblia is a single-celled eukaryotic parasite with a small genome and is considered an early divergent eukaryote. The pentose phosphate pathway (PPP) plays an essential role in the oxidative stress defense of the parasite and the production of ribose-5-phosphate. In this parasite, the glucose-6-phosphate dehydrogenase (G6PD) is fused with the 6-phosphogluconolactonase (6PGL) enzyme, generating the enzyme named G6PD::6PGL that catalyzes the first two steps of the PPP. Here, we report that the G6PD::6PGL is a bifunctional enzyme with two catalytically active sites. We performed the kinetic characterization of both domains in the fused G6PD::6PGL enzyme, as well as the individual cloned G6PD. The results suggest that the catalytic activity of G6PD and 6PGL domains in the G6PD::6PGL enzyme are more efficient than the individual proteins. Additionally, using enzymatic and mass spectrometry assays, we found that the final metabolites of the catalytic reaction of the G6PD::6PGL are 6-phosphoglucono-δ-lactone and 6-phosphogluconate. Finally, we propose the reaction mechanism in which the G6PD domain performs the catalysis, releasing 6-phosphoglucono-δ-lactone to the reaction medium. Then, this metabolite binds to the 6PGL domain catalyzing the hydrolysis reaction and generating 6-phosphogluconate. The structural difference between the G. lamblia fused enzyme G6PD::6PGL with the human G6PD indicate that the G6PD::6PGL is a potential drug target for the rational synthesis of novels anti-Giardia drugs.
AB - Giardia lamblia is a single-celled eukaryotic parasite with a small genome and is considered an early divergent eukaryote. The pentose phosphate pathway (PPP) plays an essential role in the oxidative stress defense of the parasite and the production of ribose-5-phosphate. In this parasite, the glucose-6-phosphate dehydrogenase (G6PD) is fused with the 6-phosphogluconolactonase (6PGL) enzyme, generating the enzyme named G6PD::6PGL that catalyzes the first two steps of the PPP. Here, we report that the G6PD::6PGL is a bifunctional enzyme with two catalytically active sites. We performed the kinetic characterization of both domains in the fused G6PD::6PGL enzyme, as well as the individual cloned G6PD. The results suggest that the catalytic activity of G6PD and 6PGL domains in the G6PD::6PGL enzyme are more efficient than the individual proteins. Additionally, using enzymatic and mass spectrometry assays, we found that the final metabolites of the catalytic reaction of the G6PD::6PGL are 6-phosphoglucono-δ-lactone and 6-phosphogluconate. Finally, we propose the reaction mechanism in which the G6PD domain performs the catalysis, releasing 6-phosphoglucono-δ-lactone to the reaction medium. Then, this metabolite binds to the 6PGL domain catalyzing the hydrolysis reaction and generating 6-phosphogluconate. The structural difference between the G. lamblia fused enzyme G6PD::6PGL with the human G6PD indicate that the G6PD::6PGL is a potential drug target for the rational synthesis of novels anti-Giardia drugs.
KW - Drug target
KW - Fused enzyme
KW - Giardia lamblia
KW - Glucose 6 phosphate dehydrogenase
KW - Metabolism
UR - http://www.scopus.com/inward/record.url?scp=85112666976&partnerID=8YFLogxK
U2 - 10.3390/microorganisms9081678
DO - 10.3390/microorganisms9081678
M3 - Artículo
C2 - 34442758
AN - SCOPUS:85112666976
SN - 2076-2607
VL - 9
JO - Microorganisms
JF - Microorganisms
IS - 8
M1 - 1678
ER -