Characterization of a Novel Functional Trimeric Catechol 1,2-Dioxygenase From aPseudomonas stutzeriIsolated From the Gulf of Mexico
Por:
Rodriguez-Salazar, Julieta, Almeida-Juarez, Arisbeth G., Ornelas-Ocampo, Katya, Millan-Lopez, Sofia, Raga-Carbajal, Enrique, Rodriguez-Mejia, Jose Luis, Muriel-Millan, Luis Felipe, Godoy-Lozano, E. Ernestina, Rivera-Gomez, Nancy, Rudino-Pinera, Enrique, Pardo-Lopez, Liliana
Publicada:
4 jun 2020
Resumen:
Catechol 1,2 dioxygenases (C12DOs) have been studied for its ability to
cleavage the benzene ring of catechol, the main intermediate in the
degradation of aromatic compounds derived from aerobic degradation of
hydrocarbons. Here we report the genome sequence of the marine
bacteriumPseudomonas stutzeriGOM2, isolated from the southwestern Gulf
of Mexico, and the biochemical characterization of its C12DO (PsC12DO).
ThecatAgene, encoding PsC12DO of 312 amino acid residues, was cloned and
expressed inEscherichia coli.Many C12DOs have been described as dimeric
enzymes including those present inPseudomonasspecies. The purified
PsC12DO enzyme was found as an active trimer, with a molecular mass of
107 kDa. Increasing NaCl concentration in the enzyme reaction gradually
reduced activity; in high salt concentrations (0.7 M NaCl) quaternary
structural analysis determined that the enzyme changes to a dimeric
arrangement and causes a 51% decrease in specific activity on catechol
substrate. In comparison with other C12DOs, our enzyme showed a broad
range of action for PsC12DO in solutions with pH values ranging from
neutral to alkaline (70%). The enzyme is still active after incubation
at 50 degrees C for 30 min and in low temperatures to long term storage
after 6 weeks at 4 degrees C (61%). EDTA or Ca(2+)inhibitors cause no
drastic changes on residual activity; nevertheless, the activity of the
enzyme was affected by metal ions Fe3+, Zn(2+)and was completely
inhibited by Hg2+. Under optimal conditions thek(cat)andK(m)values were
16.13 s(-1)and 13.2 mu M, respectively. To our knowledge, this is the
first report describing the characterization of a marine C12DOs fromP.
stutzeriisolated from the Gulf of Mexico that is active in a trimeric
state. We consider that our enzyme has important features to be used in
environments in presence of EDTA, metals and salinity conditions.
Filiaciones:
Rodriguez-Salazar, Julieta:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Cuernavaca, Morelos, Mexico
Almeida-Juarez, Arisbeth G.:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Cuernavaca, Morelos, Mexico
Ornelas-Ocampo, Katya:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Cuernavaca, Morelos, Mexico
Millan-Lopez, Sofia:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Cuernavaca, Morelos, Mexico
Raga-Carbajal, Enrique:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Cuernavaca, Morelos, Mexico
Rodriguez-Mejia, Jose Luis:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Cuernavaca, Morelos, Mexico
Muriel-Millan, Luis Felipe:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Cuernavaca, Morelos, Mexico
Godoy-Lozano, E. Ernestina:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Cuernavaca, Morelos, Mexico
Inst Nacl Salud Publ, Ctr Invest Enfermedades Infecciosas, Cuernavaca, Morelos, Mexico
Rivera-Gomez, Nancy:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Cuernavaca, Morelos, Mexico
Inst Nacl Salud Publ, Catedras CONACyT, Ctr Invest Salud Poblac, Cuernavaca, Morelos, Mexico
Rudino-Pinera, Enrique:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Cuernavaca, Morelos, Mexico
Pardo-Lopez, Liliana:
Univ Nacl Autonoma Mexico, Inst Biotecnol, Cuernavaca, Morelos, Mexico
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