Reaction of the catalytic cysteine of betaine aldehyde dehydrogenase from Pseudomonas aeruginosa with arsenite-BAL and phenylarsine oxide
Por:
Gonzalez-Segura, L, Mujica-Jimenez, C, Munoz-Clares, RA
Publicada:
16 mar 2009
Categoría:
Toxicology
Resumen:
Betaine aldehyde dehydrogenase (BADH) catalyses the irreversible oxidation of betaine aldehyde to glycine betaine with the concomitant reduction of NAD(P)(+) to NAD(P)H. In the opportunistic pathogen Pseudomonas aeruginosa, this enzyme (PaBADH) could be an antimicrobial target. Several aldehyde dehydrogenases (ALDHs) are inactivated by arsenite in the presence of a low molecular thiol, a finding that was interpreted as a demonstration of the existence of vicinal thiols in these enzymes. As part of our studies on the susceptibility to chemical modification of the catalytic cysteine (C286) of PaBADH, we treated the enzyme with two arsenical reagents widely used to inhibit enzymes that have vicinal thiols: sodium m-arsenite plus 2.3-dimercaptopropanol (arsenite-BAL) and phenylarsine oxide (PAO). Here we report that they readily and reversibly inactivate PaBADH, even though the four cysteine residues of this enzyme (C286, C353, C377, and C439) are far from each other in the three-dimension
Filiaciones:
Gonzalez-Segura, L:
Univ Nacl Autonoma Mexico, Fac Quim, Dept Bioquim, Mexico City 04510, DF, Mexico
Mujica-Jimenez, C:
Univ Nacl Autonoma Mexico, Fac Quim, Dept Bioquim, Mexico City 04510, DF, Mexico
Munoz-Clares, RA:
Univ Nacl Autonoma Mexico, Fac Quim, Dept Bioquim, Mexico City 04510, DF, Mexico
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