Luigi Casella, Michele Gullotti, R Ghezzi, Sonia Poli, Tiziana Beringhelli, Stefano Colonna, Giacomo Carrea,
... Gullotti, Raffaella Ghezzi, Sonia Poli, Tiziana Beringhelli, Stefano Colonna, and Giacomo CarreaCite this: Biochemistry 1992, 31, 39, 9451–9459Publication ...
Tópico(s): Electrochemical sensors and biosensors
1992 - American Chemical Society | Biochemistry
Stefano Colonna, Nicoletta Gaggero, Stefano Colonna, Giacomo Carrea, Piero Pasta,
Cyclohexanone monooxygenase from Acinetobacter catalyzes the enantioselective oxidation of organic cyclic sulfites to sulfates.
Tópico(s): Sulfur-Based Synthesis Techniques
1998 - Royal Society of Chemistry | Chemical Communications
... reality. In a famous letter to his friend Giacomo Colonna, the Bishop of Lombez, who had suggested that ...
Tópico(s): Renaissance and Early Modern Studies
2012 - Johns Hopkins University Press | MLN
A. Casavola, Gianpiero Colonna, Alessandro De Giacomo, O. De Pascale, M. Capitelli,
We present a theoretical approach to interpreting optical emission spectroscopy measurements for nonequilibrium conditions. In this approach both the fluid dynamics and the kinetics of laser-induced plasma are taken into account, and the results obtained by the numerical model are applied to the spectroscopic observation of the plasma induced by the interaction between a KrF laser and a metallic Ti target. We have generalized the theoretical method to calculate the initial conditions for the plume ...
Tópico(s): Ion-surface interactions and analysis
2003 - Optica Publishing Group | Applied Optics
A. Casavola, Gianpiero Colonna, Alessandro De Giacomo, M. Capitelli,
A model of plasma expansion with chemical kinetics has been developed and compared with the free-flow model describing the laser ablation plume of metallic titanium target. Optical emission spectroscopy has been used to obtain time of flight (TOF) spectra. The measured shift between Ti and Ti + TOF has been theoretically explained on the basis of the recombination process. Particular attention has been also focused on the dependence of TOF on some plume parameters such as initial speed, temperature, ...
Tópico(s): Atomic and Molecular Physics
2003 - American Institute of Aeronautics and Astronautics | Journal of Thermophysics and Heat Transfer
Lucia Daniela Pietanza, Gianpiero Colonna, Alessandro De Giacomo, M. Capitelli,
A zero-dimensional collisional–radiative (CR) model, coupled self-consistently with the electron Boltzmann equation, has been applied to the description of a metallic-laser induced plasma at experimental conditions typical of LIBS experiment. To take in account expansion effects, the experimental temperature and total number density as function of time have been used as input data. Plasma composition and the simultaneous time evolution of both heavy particle level distributions and the electron energy ...
Tópico(s): Analytical chemistry methods development
2010 - Elsevier BV | Spectrochimica Acta Part B Atomic Spectroscopy
A. Casavola, Gianpiero Colonna, Alessandro De Giacomo, M. Capitelli,
Tópico(s): Laser Design and Applications
2004 - Springer Science+Business Media | Applied Physics A
M. Capitelli, A. Casavola, Gianpiero Colonna, Alessandro De Giacomo,
Theoretical and experimental efforts to describe the expansion of laser-induced plasma plume are reviewed. Particular attention has been devoted to a comparison between experimental and theoretical time of flight (TOF) profiles. The theoretical results obtained by inserting plasma kinetics in one-dimensional fluid-dynamic code show that chemical processes strongly influence the fluid dynamic expansion. Moreover fluid-dynamics codes based on both Navier–Stokes and DSMC models, which in addition include ...
Tópico(s): Analytical chemistry methods development
2004 - Elsevier BV | Spectrochimica Acta Part B Atomic Spectroscopy
Salvatore Alongi, Maurizio Rolando, Angelo Macrì, Andrea Colonna, Giacomo Balestra, Rolando Rizzetto, G. Calabria,
Purpose This study quantified the bacterial load and protein deposits on 1− and 15-day disposable contact lenses after use in normal wearers. Methods. Sixteen patients were randomly assigned to a 1-day contact lens (1-Day Acuvue) in one eye and to a 15-day contact lens (Acuvue) in the contralateral eye. Only one specified solution was allowed for the care of 15-day lenses. All patients were evaluated every month for 6 months (at times T1, T2, T3, T4, T5, T6). At times T1, T3, and T5, the lenses were ...
Tópico(s): Botulinum Toxin and Related Neurological Disorders
1998 - Lippincott Williams & Wilkins | Cornea
Stefano Colonna, Nicoletta Gaggero, Giacomo Carrea, Piero Pasta,
S. Colonna, N. Gaggero, G. Carrea and P. Pasta, J. Chem. Soc., Chem. Commun., 1992, 357 DOI: 10.1039/C39920000357
Tópico(s): Enzyme Catalysis and Immobilization
1992 - Royal Society of Chemistry | Journal of the Chemical Society Chemical Communications
Stefano Colonna, Nicoletta Gaggero, Giacomo Carrea, Gianluca Ottolina, Piero Pasta, Francesca Zambianchi,
The first example of a totally enantioselective epoxidation mediated by cyclohexanone monooxygenase for a model compound related to fosfomycin is reported.
Tópico(s): Enzyme Catalysis and Immobilization
2002 - Elsevier BV | Tetrahedron Letters
Stefano Colonna, Vincenza Pironti, Giacomo Carrea, Piero Pasta, Francesca Zambianchi,
Tópico(s): Enzyme Catalysis and Immobilization
2003 - Elsevier BV | Tetrahedron
Stefano Colonna, Nicoletta Gaggereo, Giacomo Carrea, Piero Pasta,
Microperoxidase-11 catalyzed oxidation of alkyl aryl sulfides by H2O2 preferentially give the (−)-(S)-sulfoxides (e.e. 16 – 25 %).
Tópico(s): Oxidative Organic Chemistry Reactions
1994 - Elsevier BV | Tetrahedron Letters
Stefano Colonna, Nicoletta Gaggero, Giacomo Carrea, Piero Pasta,
The asymmetric oxidation of 2-substituted dithianes, dithiolanes and oxathiolanes catalyzed by cyclohexanone monooxygenase (CMO) has been examined. The introduction of substituents at the C-2 causes a decrease of the e.e. with the exception of 2-benzoyl-1,3-dithiane monosulfoxide (90% e.e.). With 2-monosubstituted dithioacetals CMO yields preferentially or exclusively the trans diastereoisomer. The binding of the 1,3-dithioacetals at the active site of the enzyme is not only controlled by the sterical ...
Tópico(s): Environmental Chemistry and Analysis
1996 - Elsevier BV | Tetrahedron Asymmetry
Stefano Colonna, Nicoletta Gaggero, Giacomo Carrea, Piero Pasta, Véronique Alphand, Roland Furstoss,
Cyclohexanone monooxygenase from Acinetobacter calcoaceticus catalyzes the asymmetric oxidation of tert-butyl disulfide to enantiomerically pure (R)-tert-butyl tert-butanethiosulfinate. Lower enantioselectivities and conversions were observed in the oxidation of i-propyl, n-butyl, p-tolyl tert-butyl disulfides and alkylthiophosphonates. Chirality 13:40–42, 2001. © 2000 Wiley-Liss, Inc.
Tópico(s): Vanadium and Halogenation Chemistry
2000 - Wiley | Chirality
Stefano Colonna, Nicoletta Gaggero, Giacomo Carrea, Piero Pasta,
S. Colonna, N. Gaggero, G. Carrea and P. Pasta, Chem. Commun., 1997, 439 DOI: 10.1039/A608352H
Tópico(s): Catalysis and Hydrodesulfurization Studies
1997 - Royal Society of Chemistry | Chemical Communications
Stefano Colonna, Nicoletta Gaggero, Luigi Casella, Giacomo Carrea, Piero Pasta,
High enantioselectivities were obtained in chloroperoxidase catalyzed oxidation of organic sulfides ( 99% ee in the case of methyl 2-pyridyl sulfide) with H2O2 in aqueous buffer solution, pH 5, at 25°C. The kinetic parameters in the oxidation of a series of sulfides both with H2O2 and tert-butyl hydroperoxide were determined and the data are consistent with enzymatic oxidation involving presumably a ternary complex, in all cases the reaction afforded the (R) sulfoxide as predominant or exclusive enantiomer.
Tópico(s): Environmental Toxicology and Ecotoxicology
1992 - Elsevier BV | Tetrahedron Asymmetry
Stefano Colonna, Nicoletta Gaggero, Luigi Casella, Giacomo Carrea, Piero Pasta,
Chloroperoxidase catalysed epoxidadon of styrene derivatives by t-BuOOH preferentially gives (R) oxides with ee values between 28 and 68%. The data support the view of oxygen delivery from the ferryl oxygen directly to the substrate.
Tópico(s): Metal-Catalyzed Oxygenation Mechanisms
1993 - Elsevier BV | Tetrahedron Asymmetry
Stefano Colonna, Nicoletta Gaggero, A. Bertinotti, Giacomo Carrea, Piero Pasta, Antonella Bernardi,
S. Colonna, N. Gaggero, A. Bertinotti, G. Carrea, P. Pasta and A. Bernardi, J. Chem. Soc., Chem. Commun., 1995, 1123 DOI: 10.1039/C39950001123
Tópico(s): Chemical Synthesis and Analysis
1995 - Royal Society of Chemistry | Journal of the Chemical Society Chemical Communications
Stefano Colonna, Simone Del Sordo, Nicoletta Gaggero, Giacomo Carrea, Piero Pasta,
Abstract Enantiomerically pure sulfoxides are excellent chiral auxiliares for asymmetric synthesis and in the preparation of several enantiopure biologically active compounds. We have explored biocatalytic approaches based on the use of heme peroxidases and flavin monooxygenases such as chloroperoxidase and cyclohexanone monooxygenase respectively. By using isolated enzymes or whole‐cell biotransformations, we have prepared alkyl aryl sulfoxides, 1,3‐dithioacetal‐1‐oxides, dialkyl sulfoxides, and ...
Tópico(s): Microbial metabolism and enzyme function
2002 - Wiley | Heteroatom Chemistry
Francesca Zambianchi, Piero Pasta, Giacomo Carrea, Stefano Colonna, Nicoletta Gaggero, John M. Woodley,
Abstract The performance, in Baeyer–Villiger and heteroatom oxidations, of a partially purified preparation of cyclohexanone monooxygenase obtained from an Escherichia coli strain in which the gene of the enzyme was cloned and overexpressed was investigated. As model reactions, the oxidations of racemic bicyclo[3.2.0]hept‐2‐en‐6‐one into two regioisomeric lactones and of methyl phenyl sulphide into the corresponding ( R )‐sulphoxide were used. Enzyme stability and reuse, substrate and product inhibition, ...
Tópico(s): Biofuel production and bioconversion
2002 - Wiley | Biotechnology and Bioengineering
Piero Pasta, Giacomo Carrea, Stefano Colonna, Nicoletta Gaggero,
At pH 3, chloride dramatically influenced both the Km of chloroperoxidase (CPO) for methyl p-tolyl sulfide, which decreased, and its activity, which increased. The Km value changed from 75 microM in the absence of chloride to < or = 1.2 microM in > or = 0.9 mM chloride, and the kcat from 53 s-1 in 0 to 1750 s-1 in 50 mM halide. The kcat/Km value at 0.9 mM chloride was 414 microM -1s-1 compared to 0.7 microM-1s-1 in the absence of the halide. At pH 5, the activating effect was less pronounced. Chloride also ...
Tópico(s): Electrochemical sensors and biosensors
1994 - Elsevier BV | Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics
Giacomo Carrea, Stefano Colonna, David R. Kelly, Antonio Lazcano, Gianluca Ottolina, Stanley M. Roberts,
Polyamino acids, such as polyleucine, behave as synthetic enzymes in the asymmetric epoxidation of chalcone and other electron-deficient alkenes (the Julià-Colonna reaction). The influences of reaction conditions, of the molecular structure of the catalysts and of the scaling-up of the process on the enantioselectivity of the reaction have been determined. The kinetics and mechanism have been investigated using a soluble PEG-polyleucine conjugate, which behaves in a similar way to an enzyme, showing ...
Tópico(s): Enzyme Catalysis and Immobilization
2005 - Elsevier BV | Trends in biotechnology
Gianluca Ottolina, Giacomo Carrea, Stefano Colonna, Andreas Rückemann,
An extension to Baeyer-Villiger oxidations of the active site model previously developed (Tetrahedron: Asymmetry, 1995, 6, 1375) for the enantioselective sulfoxidation of organic sulfides catalyzed by cyclohexanone monooxygenase from Acinetobacter NCIMB 9871 is proposed. The model is based on cubic-space descriptors and can explain the stereoselectivity of the enzyme for about 40 different substrates.
Tópico(s): Metalloenzymes and iron-sulfur proteins
1996 - Elsevier BV | Tetrahedron Asymmetry
Giacomo Carrea, Stefano Colonna, Alastair Meek, Gianluca Ottolina, Stanley M. Roberts,
Tópico(s): Carbohydrate Chemistry and Synthesis
2004 - Elsevier BV | Tetrahedron Asymmetry
Giacomo Carrea, Stefano Colonna, Alastair Meek, Gianluca Ottolina, Stanley M. Roberts,
An insight into the kinetics, mechanism and optimum reaction conditions of the Julia-Colonna epoxidation has been gained using a soluble polyleucine catalyst.
Tópico(s): Oxidative Organic Chemistry Reactions
2004 - Royal Society of Chemistry | Chemical Communications
Francesca Zambianchi, Piero Pasta, Gianluca Ottolina, Giacomo Carrea, Stefano Colonna, Nicoletta Gaggero, John M. Ward,
Tópico(s): Chemical Synthesis and Reactions
2000 - Elsevier BV | Tetrahedron Asymmetry
Emiliano Casati, S. Vitale, Matteo Pini, Giacomo Persico, Piero Colonna,
Organic Rankine cycle (ORC) power systems are rapidly diffusing as a technology for the conversion of thermal energy sources in the small-to-medium power range, e.g., from 150 kWe up to several MWe. The most critical component is arguably the expander, especially if the power capacity is small or very small, as it is the case for innovative high-potential applications such as waste heat recovery from truck engines, or distributed conversion of concentrated solar radiation. In these so-called high- ...
Tópico(s): Refrigeration and Air Conditioning Technologies
2014 - ASM International | Journal of Engineering for Gas Turbines and Power
Gianluca Ottolina, Piero Pasta, Giacomo Carrea, Stefano Colonna, Sabrina Dallavalle, Herbert L. Holland,
An active site model to explain and predict the stereoselectivity of the sultoxidation of organic sulfides to optically active sulfoxides catalyzed by cyclohexanone monooxygenase from Acinetobacter NCIB 9871 is proposed. The model is based on cubic-space descriptors and derives from the results obtained with over 30 different sulfides. The model, which also appears to be suitable for explaining the stereoselectivity of cyclohexanone monooxygenase-catalyzed Baeyer-Villiger reactions, is consistent ...
Tópico(s): Enzyme Catalysis and Immobilization
1995 - Elsevier BV | Tetrahedron Asymmetry
Chantal Capeillère‐Blandin, Christelle Martin, Nicoletta Gaggero, Piero Pasta, Giacomo Carrea, Stefano Colonna,
The oxidation of alkyl aryl sulphides by myeloperoxidase (MPO) at the expense of hydrogen peroxide was investigated under steady-state conditions. The sulphide concentration effect was studied under saturating H2O2 concentrations at pH 5.0 and 20 °C. The kinetic constants, kcat and Km, of the different substrates were determined and the values were in the 1–10 s-1 range and around 43±26 µM respectively, whatever the sulphide considered. In the case of p-substituted thioanisoles, the oxidation rate ...
Tópico(s): Neutrophil, Myeloperoxidase and Oxidative Mechanisms
1998 - Portland Press | Biochemical Journal