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Dr.
 
A. Jalila
 
SIMAAN

Dr. A. jalila Simaan's picture
Dr.
A. Jalila
SIMAAN
AMU iSm2 Service 342
Campus Scientifique de St Jérôme
13397
Marseille cedex 20


Phone number
Fax
0491 28 84 40

Career path
2016: CNRS director
2002: CNRS researcher in Marseille
2000-2001 : Postdoc in Raman Spectroscopy with Prof. Peter Hildebrandt/ Max Planck Institut für Strahlenchemie, Mülheim / Ruhr (Allemagne) et à Instituto de Tecnológia Química e Biológica, Oeiras (Portugal)
1997-2000 : PhD in Bio-inorganique chemistry, Paris-Sud University (Orsay) / Prof Jean-Jacques GIRERD and Frédéric Banse
1996 :«Agrégation externe de Sciences Physiques Option Chimie ».
1993 -1997: Student at the « Ecole Normale Supérieure de Cachan »  Chemistry department. Physical Chemistry studies at Université Paris-Sud, Orsay.
Research themes

Copper containing Monooxygenases enzymes and model complexes

In collaboration with Marius Réglier, Christophe Decroos, Bruno Faure, Maylis Orio (iSm2/BiosCiences)
Current PhD students: Alessia Munzone (with C. Decroos, 2017-) & Rogelio Gomez Pineiro (with M. Orio, 2018-)

Copper containing Monooxygenases couple dioxygen reductive activation to oxygen atom transfer into a substrate's C-H bond. Copper Monooxygenases display active sites of diverse nuclearities and structures. We are interested in several monooxygenases and in particular, in Lytic Polysaccharide Monooxygenases or LPMOs, mononuclear copper-containing enzymes that boost recalcitrant polysaccharide degradation (biomass) via oxidative pathways. LPMO possess a rare coordination motif: the N-terminal histidine is bound to the copper ion via both its imidazole ring and the amino terminal group (Histidine-brace motif).

Our studies are centered on  :

  • Understanding the mechanism of enzymatic systems (e.g. LPMOs)
  • Preparing copper-containing bio-inspired models and trapping reaction intermediates
  • Performing water oxidation/activation with copper complexes

External collaborations: Dr. Catherine Belle, Dr. Hélène Jamet and Dr. Aurore Thibon-Pourret (Université Grenoble-Alpes / CNRS); Dr. Nicolas Le Poul (Université de Bretagne Occidentale, CNRS); Prof. Ivan Castillo (UNAM, Mexico, ECOS-Nord project);

ACC Oxidase, a non-heme iron(II) enzyme

PhD student (past): Dr. Eugénie Fournier (with Prof. V. Belle, 2015-2018)

The plant hormone ethylene is essential for many aspects of plant life germination, senescence, fruit ripening and defense mechanisms. Ethylene is directly biosynthesized from 1-aminocyclopropane carboxylic acid (ACC), a metabolite of methionine. This step is catalyzed by ACC Oxidase a non-heme iron(II) containing enzyme. The conversion of ACC into ethylene requires the presence of ferrous ions, dioxygen and ascorbate. In addition, ACCO also requires the presence of CO2 (or HCO3-) for activity.

The crystallographic structures revealed a coeur folded in beta barrel that contains the active site. The iron(II)  ion is coordinated by the side chains of 2 histidines and one aspartate in a classical facial triad. Although several set of structures have been obtained, there are still question on the active conformation of the enzyme and in particular, that of the C-terminal part (in red on the figure ).Thanks to an interdisciplinary approach we aim at getting more information on this enzyme 

Our studies are centered on:

  • Understanding the mode of action of the enzyme
  • Exploring metal / activity modification
  • Getting information on the active conformation and dynamic of the C-terminal part
  • preparing model complexes

External collaborations: Prof. Valérie Belle and Dr. Marlène Martinho (Université d'Aix-Marseille); Prof. Christian Limberg (Humboldt University, Berlin, Germany); Prof. József Kaizer (University of Pannonia, Veszprém, Hungary); Dr. Wadih Ghattas & Prof. Jean-Pierre Mahy (Université Paris-Saclay)

Publications (54)
ReferenceGraphical Abstracts
Photoinduced Multielectron Transfer to a Multicopper Oxidase Resulting in Dioxygen Reduction into Water

A. Jalila Simaan, Yasmina Mekmouche, Christian Herrero, Pierre Moreno, Ally Aukauloo, Jacques Delaire, Marius Réglier, Thierry Tron, Chemistry - A European Journal, 2011, 17, 11743-11746. <hal-02096695>
Bio-inspired amino acid oxidation by a non-heme iron catalyst modeling the action of 1-aminocyclopropane-1-carboxylic acid oxidase

Gábor Baráth, József Kaizer, József Sándor Pap, Gábor Speier, Nadia El Bakkali-Taheri, A. Jalila Simaan Chem Commun. 2010, 46, 7391-7393
Binding of 2-Hydroxypyridine- N -oxide on Dicopper(II) Centers: Insights into Tyrosinase Inhibition Mechanism by Transition-State Analogs

Eugénie Peyroux, Wadih Ghattas, Renaud Hardré, Michel Giorgi, Bruno Faure, A. Jalila Simaan, Catherine Belle, Marius Réglier, Inorganic Chemistry, 2009, 48, 10874 - 10876. <hal-01658950>
Synthesis and Characterization of a Binuclear Iron(III) Complex Bridged by 1-Aminocyclopropane-1-carboxylic Acid. Ethylene Production in the Presence of Hydrogen Peroxide

Wadih Ghattas, Zeinab Serhan, Nadia El Bakkali-Taheri, Marius Reglier, Masahito Kodera, Yutaka Hitomi, A. Jalila Simaan Inorg. Chem.. 2009, 48, 3910-3912
Identification of a Copper(I) Intermediate in the Conversion of 1-Aminocyclopropane Carboxylic Acid (ACC) into Ethylene by Cu(II)−ACC Complexes and Hydrogen Peroxide

Wadih Ghattas, Michel Giorgi, Yasmina Mekmouche, Tsunehiro Tanaka, Antal Rockenbauer, M. Réglier, Yutaka Hitomi, A. Jalila Simaan, Inorganic Chemistry, 2008, 47, 4627-4638. <hal-01948939>
ACC-Oxidase like activity of a copper (ii)–ACC complex in the presence of hydrogen peroxide. Detection of a reaction intermediate at low temperature

Wadih Ghattas, Christian Gaudin, Michel Giorgi, Antal Rockenbauer, A. Jalila Simaan, Marius Réglier, Chemical Communications, 2006, 1027. <hal-02096709>

Pages

Chapters of books (2)
ReferenceGraphical Abstracts
A. Jalila Simaan, Alda Lisa Concia, Alessia Munzone, Maria-Chrysanthi Kafentzi, Amélie Kochem, et al.. Modeling the Mononuclear Copper Monooxygenase Active Site. Series on Chemistry, Energy and the Environment: Volume 5 Bioinspired Chemistry; From Enzymes to Synthetic Models, pp.185-263, 2019, ⟨10.1142/9789813274440_0008⟩. ⟨hal-02094996⟩
A. Jalila Simaan, Marius Réglier. CHAPTER 20. 1-Aminocyclopropane-1-Carboxylic Acid Oxidase. 2-oxoglutarate-dependent oxygenases RSC Metallobiology Series, 3., pp.425-437, 2015, ⟨10.1039/9781782621959-00425⟩. ⟨hal-02095042⟩