Publications

• Biodegradation of aromatic compounds by Escherichia coli.

  Diaz E., Ferrandez A., Prieto M.A., Garcia J.L.

  Although Escherichia coli has long been recognized as the best-understood living organism, little was known about its abilities to use aromatic compounds as sole carbon and energy sources. This review gives an extensive overview of the current knowledge of the catabolism of aromatic compounds by E ... >> More

  Although Escherichia coli has long been recognized as the best-understood living organism, little was known about its abilities to use aromatic compounds as sole carbon and energy sources. This review gives an extensive overview of the current knowledge of the catabolism of aromatic compounds by E. coli. After giving a general overview of the aromatic compounds that E. coli strains encounter and mineralize in the different habitats that they colonize, we provide an up-to-date status report on the genes and proteins involved in the catabolism of such compounds, namely, several aromatic acids (phenylacetic acid, 3- and 4-hydroxyphenylacetic acid, phenylpropionic acid, 3-hydroxyphenylpropionic acid, and 3-hydroxycinnamic acid) and amines (phenylethylamine, tyramine, and dopamine). Other enzymatic activities acting on aromatic compounds in E. coli are also reviewed and evaluated. The review also reflects the present impact of genomic research and how the analysis of the whole E. coli genome reveals novel aromatic catabolic functions. Moreover, evolutionary considerations derived from sequence comparisons between the aromatic catabolic clusters of E. coli and homologous clusters from an increasing number of bacteria are also discussed. The recent progress in the understanding of the fundamentals that govern the degradation of aromatic compounds in E. coli makes this bacterium a very useful model system to decipher biochemical, genetic, evolutionary, and ecological aspects of the catabolism of such compounds. In the last part of the review, we discuss strategies and concepts to metabolically engineer E. coli to suit specific needs for biodegradation and biotransformation of aromatics and we provide several examples based on selected studies. Finally, conclusions derived from this review may serve as a lead for future research and applications. << Less

  Microbiol Mol Biol Rev 65:523-569(2001) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.

• Purification, characterization, and crystallization of monoamine oxidase from Escherichia coli K-12.

  Roh J.H., Suzuki H., Azakami H., Yamashita M., Murooka Y., Kumagai H.

  The gene for monoamine oxidase (MAO) was cloned from an Escherichia coli genomic library and MAO was overproduced in the periplasmic space. The enzyme was purified to homogeneity by preparation of a periplasmic fraction, followed by ammonium sulfate fractionation and DEAE-cellulose column chromato ... >> More

  The gene for monoamine oxidase (MAO) was cloned from an Escherichia coli genomic library and MAO was overproduced in the periplasmic space. The enzyme was purified to homogeneity by preparation of a periplasmic fraction, followed by ammonium sulfate fractionation and DEAE-cellulose column chromatography. Crystals were obtained by the hanging drop method using sodium citrate as a precipitant. The enzyme was found to be a dimer of identical subunits with a molecular weight of 80,000, and showed the highest activity at pH 7.5 and 45 degrees C. The enzyme was inhibited by a MAO specific inhibitor, hydroxylamine, hydrazine, phenelzine, isoniazid, and tranycpromine. The enzyme oxidized tyramine, phenethylamine, and tryptamine at higher rates, but not oxidized diamine and polyamines such as putrescine and spermine. The antibody against E. coli MAO cross-reacted with purified MAO A from Klebsiella aerogenes. << Less

  Biosci Biotechnol Biochem 58:1652-1656(1994) [PubMed] [EuropePMC]

• 90 years of monoamine oxidase: some progress and some confusion.

  Tipton K.F.

  It would not be practical to attempt to deal with all the advances that have informed our understanding of the behavior and functions of this enzyme over the past 90 years. This account concentrates key advances that explain why the monoamine oxidases remain of pharmacological and biochemical inte ... >> More

  It would not be practical to attempt to deal with all the advances that have informed our understanding of the behavior and functions of this enzyme over the past 90 years. This account concentrates key advances that explain why the monoamine oxidases remain of pharmacological and biochemical interest and on some areas of continuing uncertainty. Some issues that remain to be understood or are in need of further clarification are highlighted. << Less

  J Neural Transm (Vienna) 125:1519-1551(2018) [PubMed] [EuropePMC]

  This publication is cited by 6 other entries.

• A key amino acid responsible for substrate selectivity of monoamine oxidase A and B.

  Tsugeno Y., Ito A.

  Monoamine oxidase (MAO) oxidizes biologically important amines including neurotransmitters and plays a central role in the regulation of intracellular level of these amines. Two distinct forms of MAO (MAO A and MAO B) were defined based on differences in substrate and inhibitor specificities. We e ... >> More

  Monoamine oxidase (MAO) oxidizes biologically important amines including neurotransmitters and plays a central role in the regulation of intracellular level of these amines. Two distinct forms of MAO (MAO A and MAO B) were defined based on differences in substrate and inhibitor specificities. We earlier reported that the region between about residues 120 and 220 of rat MAO is responsible for determination of the substrate selectivity of MAO A and B (Tsugeno, Y. Hirashiki, I., Ogata, F., and Ito, A. (1995) J. Biochem. (Tokyo) 118, 974-980). To determine the essential amino acids in this region that participate in substrate recognition, a series of mutant enzymes in which amino acid residues that are conserved among various species but are different between the two forms of the enzyme were replaced with the corresponding amino acids of the counterpart and were engineered from the cDNAs of rat liver MAO A and B, and affinities for several substrates were examined. A single mutation in which Phe-208 in MAO A was substituted by the corresponding residue of Ile in MAO B was sufficient to convert the A-type substrate selectivity, and the reverse was exactly the case. Phe at this position was replaceable with Tyr for the A-type specificity and Ile was replaceable with Val and Ala for the B-type. Thus, aromatic and aliphatic residues seem to contribute to render substrate selectivity of MAO A and MAO B, respectively. << Less

  J. Biol. Chem. 272:14033-14036(1997) [PubMed] [EuropePMC]

  This publication is cited by 3 other entries.

• The unique substrate specificity of human AOC2, a semicarbazide-sensitive amine oxidase.

  Kaitaniemi S., Elovaara H., Groen K., Kidron H., Liukkonen J., Salminen T., Salmi M., Jalkanen S., Elima K.

  Semicarbazide-sensitive amine oxidases (SSAOs) catalyze oxidative deamination of primary amines, but the true physiological function of these enzymes is still poorly understood. Here, we have studied the functional and structural characteristics of a human cell-surface SSAO, AOC2, which is homolog ... >> More

  Semicarbazide-sensitive amine oxidases (SSAOs) catalyze oxidative deamination of primary amines, but the true physiological function of these enzymes is still poorly understood. Here, we have studied the functional and structural characteristics of a human cell-surface SSAO, AOC2, which is homologous to the better characterized family member, AOC3. The preferred in vitro substrates of AOC2 were found to be 2-phenylethylamine, tryptamine and p-tyramine instead of methylamine and benzylamine, the favored substrates of AOC3. Molecular modeling suggested structural differences between AOC2 and AOC3, which provide AOC2 with the capability to use the larger monoamines as substrates. Even though AOC2 mRNA was expressed in many tissues, the only tissues with detectable AOC2-like enzyme activity were found in the eye. Characterization of AOC2 will help in evaluating the contribution of this enzyme to the pathological processes attributed to the SSAO activity and in designing specific inhibitors for the individual members of the SSAO family. << Less

  Cell. Mol. Life Sci. 66:2743-2757(2009) [PubMed] [EuropePMC]

  This publication is cited by 4 other entries.

• Kinetic mechanism of monoamine oxidase A.

  Ramsay R.R.

  Steady-state kinetic data for monoamine oxidase A in crude extracts suggest an exclusively ping-pong mechanism, in contrast to those for monoamine oxidase B, which indicate alternate mechanisms involving either a binary or ternary complex. In this study, with use of purified monoamine oxidase A, s ... >> More

  Steady-state kinetic data for monoamine oxidase A in crude extracts suggest an exclusively ping-pong mechanism, in contrast to those for monoamine oxidase B, which indicate alternate mechanisms involving either a binary or ternary complex. In this study, with use of purified monoamine oxidase A, steady-state data for the inhibition by D-amphetamine of the oxidation of primary amines indicate the possibility of a ternary complex mechanism for monoamine oxidase A also. Stopped-flow studies demonstrate that the rate of reoxidation of reduced enzyme is enhanced by substrates but not by the product, 1-methyl-4-phenylpyridinium. Thus, for the A enzyme, the ternary complex with substrate, but not product, is reoxidized at a faster rate than the free, reduced enzyme. For both the A and B forms of monoamine oxidase, the mechanism is determined by competition between alternate pathways on the basis of the relative rate constants and dissociation constants. << Less

  Biochemistry 30:4624-4629(1991) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.

• The oxidation of adrenaline and noradrenaline by the two forms of monoamine oxidase from human and rat brain.

  O'Carroll A.M., Bardsley M.E., Tipton K.F.

  The selective monoamine oxidase inhibitors clorgyline and (?)-deprenyl were used to study the distribution of monoamine oxidase-A and -B (MAO-A, MAO-B) activities towards (?)-noradrenaline and (+),(?)-adrenaline in homogenates from seven different regions of human brain. The activities towards 5-h ... >> More

  The selective monoamine oxidase inhibitors clorgyline and (?)-deprenyl were used to study the distribution of monoamine oxidase-A and -B (MAO-A, MAO-B) activities towards (?)-noradrenaline and (+),(?)-adrenaline in homogenates from seven different regions of human brain. The activities towards 5-hydroxytryptamine and 2-phenethylamine, which are essentially specific substrates for the A- and B-forms, respectively, under the conditions used in this work, were also determined. Noradreanline and adrenaline were substrates for both forms of the enzyme in all regions studied. The total MAO activity was found to be highest in the hypothalamus and lowest in the cerebellar cortex. Use of the selective MAO inhibitors clorgyline and (?)-deprenyl also showed adrenaline and noradrenaline to be substrates for both forms of the enzyme in rat brain. In human cerebral cortex and rat brain the two forms were found to have similar K(m)-values and maximum velocities towards adrenaline. These values for the two forms were also found to be similar in human cerebral cortex when noradrenaline was used as the substrate. In contrast MAO-A showed a significantly lower K(m) and a higher maximum velocity towards noradrenaline in rat brain. These results suggest that the rat may not provide a close model of the human for studies on the effects of MAO inhibitors on brain noradrenaline metabolism. << Less

  Neurochem. Int. 8:493-500(1986) [PubMed] [EuropePMC]

  This publication is cited by 5 other entries.