Poster
# 58
Poster |
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6th Internet World Congress for Biomedical Sciences |
Pilar Gutiérrez Navarro(1), Iluminada Hernández(2), Pedro Martínez de las Parras(3), Abdelkrim El Bekkouri(4), Raquel García(5)
(1)Facultad de Farmacia. Universidad de Granada. - Granada. Spain
(2)Departamento de Química Física.. Universidad de Granada - Granada. Spain
(3)Dpto. Química Física. Universidad de Granada - Granada. Spain
(4)(5)Dpto. Quimica Fisica. Universidad de Granada - Granada. Spain
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Contact address: |
Pilar Gutiérrez Navarro Facultad de Farmacia. Universidad de Granada. Pilar Gutierrez Navarro. Facultad de Farmacia. Poligono Universitario de Cartuja. Granada Granada 18071 Spain mpgn@platon.ugr.es |
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[Biophysics] |
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[Biochemistry] |
Bacterial resistence to the beta-lactams antibiotics is atributted to the presence of a beta-lactamase enzymes which catalyses the amide bond hydrolysis of the 4-member ring in these antibiotics. Nowadays, the beta-lactamases are classified into four groups. The classes 1, 2 and 4 are characterized by the involvement of a serine rest in the active for the nucleophilic attack in the carbonyl beta-lactam whereas those pertaining to the class 3 are metalloenzymes requiring metal ions (Zn [II], Cd [II], Co [II] or Mn [II]) for catalytic activity (1,2).
The metalloenzymes are produced by a great number of microorganisms. Moreover, the recognized ability of the metalloenzymes to produce the hydrolysis of carbapenems, what is not usually accomplished by the enzymes containing serine active-site, has increased enormously the interest for this class of enzymes (3).
At the moment, there is not specific inhibitors useful in therapeutical treatment because of the mechanism of action of the enzymes remains still unclair. The studies currently devoted to the metalloenzymes are focused on the interaction between the enzyme and the metal ion in order to establish the role of the different metal ions in the catalytic activity (4,5).
Taking into account the interest of the interaction of the metal ion with the antibiotic, we have carried out a kinetic study of the degradation of several beta-lactams antibiotics in the presence of those metal ion which are related to the metalloenzymes. Absorption and fluorescence measurements indicate the formation of a possible cyclic compound derived from the methanolysis of ampicillin, amoxicillin, imipenem, meropenem and cephaloxin. Spectral features have been used to monitor the antibiotic decomposition reaction allowing us to obtain the kinetic equation. In general , we have found that these kind of reactions proceed according to a scheme of a consecutive reactions.
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[Biophysics] |
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[Biochemistry] |
