caa a22 4500 475744365 CHVBK 20180406123508.0 cr unu---uuuuu 170329e20001101xx s 000 0 eng 10.1023/A:1007116703991 doi (NATIONALLICENCE)springer-10.1023/A:1007116703991 Purification and Catalytic Properties of Two Catechol 1,2-Dioxygenase Isozymes from Benzoate-Grown Cells of Acinetobacter radioresistens [Elektronische Daten] [Fabrizio Briganti, Enrica Pessione, Carlo Giunta, Roberto Mazzoli, Andrea Scozzafava] Two catechol 1,2-dioxygenase (C1,2O) isozymes (IsoA and IsoB) have been purified to homogeneity from a strain of Acinetobacter radioresistens grown on benzoate as the sole carbon and energy source. IsoA and IsoB are both homodimers composed of a single type of subunit with molecular mass of 38,600 and 37,700, Da respectively. In conditions of low ionic strength, IsoA can aggregate as a trimer, in contrast to IsoB, which maintains the dimeric structure, as also supported by the kinetic parameters (Hill numbers). IsoA is identical to the enzyme previously purified from the same bacterium grown on phenol, whereas the IsoB is selectively expressed using benzoate as carbon source. This is the first evidence of the presence of differently expressed C1,2O isozymes in A. radioresistens or more generally of multiple C1,2O isozymes in benzoate-grown Acinetobacter cells. Purified IsoA and IsoB contain approximately 1 iron(III) ion per subunit and both show electronic absorbance and EPR features typical of Fe(III) intradiol dioxygenases. The kinetic properties of the two enzymes such as the specificities toward substituted catechols, the main catalytic parameters, and their behavior in the presence of different kind of inhibitors are, unexpectedly, very similar, in contrast to most of the previously known dioxygenase isozymes. Plenum Publishing Corporation, 2000 Catechol 1,2-dioxygenase nationallicence intradiol dioxygenase nationallicence aromatic compound degradation nationallicence Acinetobacter radioresistens nationallicence isozymes nationallicence differential expression nationallicence Briganti Fabrizio Dipartimento di Chimica, Università degli Studi di Firenze, 50121, Florence, Italy aut Pessione Enrica Dipartimento di Biologia Animale, Università di Torino, 10100, Turin, Italy aut Giunta Carlo Dipartimento di Biologia Animale, Università di Torino, 10100, Turin, Italy aut Mazzoli Roberto Dipartimento di Biologia Animale, Università di Torino, 10100, Turin, Italy aut Scozzafava Andrea Dipartimento di Chimica, Università degli Studi di Firenze, 50121, Florence, Italy aut Journal of Protein Chemistry Kluwer Academic Publishers-Plenum Publishers 19/8(2000-11-01), 709-716 0277-8033 19:8<709 2000 19 10930 https://doi.org/10.1023/A:1007116703991 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1007116703991 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Briganti Fabrizio Dipartimento di Chimica, Università degli Studi di Firenze, 50121, Florence, Italy aut NATIONALLICENCE 700 1- Pessione Enrica Dipartimento di Biologia Animale, Università di Torino, 10100, Turin, Italy aut NATIONALLICENCE 700 1- Giunta Carlo Dipartimento di Biologia Animale, Università di Torino, 10100, Turin, Italy aut NATIONALLICENCE 700 1- Mazzoli Roberto Dipartimento di Biologia Animale, Università di Torino, 10100, Turin, Italy aut NATIONALLICENCE 700 1- Scozzafava Andrea Dipartimento di Chimica, Università degli Studi di Firenze, 50121, Florence, Italy aut NATIONALLICENCE 773 0- Journal of Protein Chemistry Kluwer Academic Publishers-Plenum Publishers 19/8(2000-11-01), 709-716 0277-8033 19:8<709 2000 19 10930 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer