Enzymology external website

Enzymology Department


Our central research topic is the study of structure-function relationships in signaling enzymes, with a focus on protein tyrosine phosphatases. The aim is to contribute to the understanding of how their structural features are correlated with specific signaling functions. To this end, signaling enzymes are studied from several directions:

  • as a classical enzyme, trying to evaluate enzymes stability under different conditions, the pH dependence of the activity, the specific activity, the kinetic parameters at the steady state, the substrate specificity and also the identification of the specific inhibitors 
  • as a protein, trying to crystallize the purified enzyme preparation and then determine its 3D structure
  • as a signaling entity, trying to find its subcellular location, substrate(s), regulatory interactions, role played in signaling pathways, etc.

The combination of results thus obtained in this way is further used to shed light on the signaling mechanism and overall functional role of the given enzyme.

We have good experience and we are currently involved in the production, isolation and purification of recombinant proteins, expressed in both prokaryotic and eukaryotic systems. Our research activity is carried out through tools of molecular biology (recombinant DNA, site-directed mutagenesis, (RT)-PCR, Western blot, immunoprecipitation, etc.), spectroscopic analysis (UV-VIS and fluorescent spectrophotometry), cell biology, protein crystallization and enzyme kinetics.

Our ongoing research projects are:

  • Design, preparation, characterization and testing of new molecular vectors targeting specific leukemic cells for targeted diagnosis and targeted therapy
  • Study of tau protein acetylation and its involvement in neurodegenerative diseases 

Current research directions:

(a) expression, purification and study of the mechanism of action of some proteins involved in synaptic transmission;

(b) creation of new conjugates based on afibodies with a potential therapeutic role in different forms of leukemia;

(c) biochemical study of tau protein acetylation with applicability in neurodegenerative diseases;

(d) study of signaling mechanisms involved in various cancer forms



            External website: full link: https://www.nipne.ro/proiecte/pn3/20-projects.html



   External website: full link: https://www.nipne.ro/proiecte/pn3/9-projects.html


                          External website: full link: https://www.icbp.ro/static/en/en-networking_grants-grants national_grants/pcca1contract_792012.html

 External website: full link: https://www.nipne.ro/proiecte/pn2/149-projects.html



Outstanding researchers who have made a significant contribution to the advancement of knowledge in their field, demonstrating the importance of the solid foundation provided by the Department of Enzymology in their professional training.


  2005 - 2015

2005 - 2015

2015 -2023

2015 -2023





























Under construction

Stefan Szedlacsek, Dr.
Stefan Szedlacsek, Dr.

Head of Department

Prof. Dr. Stefan Szedlacsek is the Head of the Enzymology Department at the Institute of Biochemistry of the Romanian Academy. He holds a PhD degree in Biotechnology from Polytechnical University of Bucharest as well as a MSc in Organic Synthesis (Polytechnical University, Bucharest) and MSc in Mathematics (University of Bucharest). As a visiting scientist, he performed research in the field of cholesterol metabolism at the University of Illinois at Urbana-Champaign (USA), where he succeeded to evidence a new pathway in the metabolism of oxysterols.  He is an “Alexander von Humboldt” fellow and worked in Germany, in the Institute of Biochem More...

Adina-Gabriela Puiu, PhD Student
Adina-Gabriela Puiu, PhD Student

Research Assistant

Adina has a Bachelor's degree in Biology and a Master's degree in Applied Genetics and Biotechnology from the Faculty of Biology, University of Bucharest. She is a PhD student and Research Assistant at the Institute of Bio More...

Andra-Elena Cosoreanu
Andra-Elena Cosoreanu

Andra-Elena Cosoreanu is a researcher in the Institute of Biochemistry of the Romanian Academy. Andra-Elena is currently working in Enzymology in the Enzymology.

Andrei-Mihai Vasilescu, PhD Student
Andrei-Mihai Vasilescu, PhD Student

Research Assistant

Andrei-Mihai Vasilescu is a researcher in the Institute of Biochemistry of the Romanian Academy. Andrei-Mihai is currently working in Enzymology in the Enzymology.

Bica Constantin Catalin, MSc
Bica Constantin Catalin, MSc


Bica Constantin Catalin is a researcher in the Institute of Biochemistry of the Romanian Academy. Bica is currently working in Enzymology in the Enzymology.

Horea Szedlacsek
Horea Szedlacsek

Research Assistant

Horea Szedlacsek is a researcher in the Institute of Biochemistry of the Romanian Academy. Horea is currently working in Enzymology in the Enzymology.

Otilia-Cristina Donțu, Ms.
Otilia-Cristina Donțu, Ms.


2008 - 2012: Bachelor's Degree in Economics, specialising in Accounting and Management Information Systems, Faculty of Economics and Business Administration, "Dunarea de Jos" University, Galati, Romania. 2021 - 2024: More...

Viorel Enache, MSc.
Viorel Enache, MSc.

Research Assistant

Viorel Enache is a researcher in the Institute of Biochemistry of the Romanian Academy. Viorel is currently working in Enzymology in the Enzymology.


1. "Synthesis and characterization of a novel [52Mn]Mn-labelled affibody based radiotracer for HER2+ targeting"; Balázs-Váradi, Károly-Brezovcsik, Zoltán Garda, Eniko-Madarasi, Horea-Szedlacsek,  Rodica-Aura Badea,  Andrei-Mihai Vasilescu,  Adina-Gabriela Puiu, Aura Ionescu,  Livia-Elena Sima,  Cristian V.A. Munteanu,  Simona Călăraș,  Adrienn Vagner,  Dezső Szikra,  Ngô Minh Toàn,  Tibor Nagy,  Zoltán Szűcs, Stefan Eugen Szedlacsek, Inorganic Chemistry Frontiers,  Published: 06 Jun 2023DOI:10.1039/D3QI00356F

2. "Designed Peptide Inhibitors of STEP Phosphatase-GluA2 AMPA Receptor Interaction Enhance the Cognitive Performance in Rats";  Szedlacsek HS, Bajusz D, Badea RA, Pop A, Bică CC, Ravasz L, Mittli D, Mátyás D, Necula-Petrăreanu G, Munteanu CVA, Papp I, Juhász G, Hritcu L, Keserű GM, Szedlacsek SE. J Med Chem. 2022 Jan;  DOI: 10.1021/acs.jmedchem.1c01303

3."Trojan horse treatment based on PEG-coated extracellular vesicles to deliver doxorubicin to melanoma in vitro and in vivo";  Patras L, Ionescu AE, Munteanu C, Hajdu R, Kosa A, Porfire A, Licarete E, Rauca VF, Sesarman A, Luput L, Bulzu P, Chiroi P, Tranca RA, Meszaros MS, Negrea G, Barbu-Tudoran L, Potara M, Szedlacsek S, Banciu M. Cancer Biol Ther. ; DEC 31 2022DOI: 10.1080/15384047.2021.2003656

4. “Comparative Analysis Between Cellular Oncogenes and Viral Oncogenes"; Biointerface Research in Applied Chemistry 11(3): 9939-9951,; Puiu, AG; Grigoras, O; Preda, MI; Constantin, M; Vasilescu, AM.; 2021; Review: doi: 10.33263/BRIAC113.99399951

5. ”Regulation of TRPM8 Channel activity by Src-mediated Tyrosine Phosphorylation”;  Alexandra Manolache, Tudor Selescu, G. Larisa Maier, Mihaela Mentel, Aura Elena Ionescu, Cristian Neacșu, Alexandru Babeș, Ștefan Eugen Szedlacsek. Journal of Cellular Physiology; June 2020DOI: 10.1002/jcp.29397

6. ”Analysis of EYA3 phosphorylation by Src kinase identifies residues involved in cell Proliferation”; Aura E. Ionescu, Mihaela Mentel, Cristian V.A. Munteanu, Livia E. Sima, Eliza  C. Martin, Georgiana Necula-Petrareanu and Ștefan E. Szedlacsek. International Journal of Molecular Sciences, Volume 20, Issue 24, 6307; 2019; DOI: 10.3390/ijms20246307

7.  ”Biological and molecular modifications induced by cadmium and arsenic during breast and prostate cancer development”;   Environmental Research; Zimta, AA; Schitcu, V; Gurzau, E; Stavaru, C ; Manda, G; Szedlacsek, S; Berindan-Neagoe, Volume: 178, Article Number: 108700; 2019; DOI: 10.1016/j.envres.2019.108700

8. ”Crystal structure of a xylulose 5-phosphate phosphoketolase. Insights into the substrate specificity for xylulose 5-phosphate”, Journal of Structural Biology; Scheidig, AJ ; Horvath, D; Szedlacsek, SE , Volume 207, Issue 1, Page 85-102; 2019;  DOI: 10.1016/j.jsb.2019.04.017

9. ’’Collagen regulates the ability of endothelial progenitor cells to protect hypoxic myocardium through a mechanism involving miR-377/VE-PTP axis”; Rosca AM, Mitroi DN, Cismasiu V, Badea R, Necula-Petrareanu G, Preda MB, Niculite C, Tutuianu R, Szedlacsek S, Burlacu A. J Cell Mol Med. 22, 4700-4708; 2018; DOI: 10.1111/jcmm.13712

10. ’’WDR1 is a novel EYA3 substrate and its dephosphorylation induces modifications of the cellular actin cytoskeleton”; Mentel M, Ionescu AE, Puscalau-Girtu I, Helm MS, Badea RA, Rizzoli SO, Szedlacsek SE. Sci Rep. 8, 2910; 2018; DOI:10.1038/s41598-018-21155-w

11. “Phosphoketolases from Lactococcus lactis, Leuconostoc mesenteroides and Pseudomonas aeruginosa: dissimilar sequences, similar substrates but distinct enzymatic characteristics“; Petrareanu G, Balasu MC, Vacaru AM, Munteanu CV, Ionescu AE, Matei I, Szedlacsek SE. Appl Microbiol Biotechnol. 98, 7855-67; 2014; DOI: 10.1007/s00253-014-5723-6

12. “Protein tyrosine phosphatase structure-function relationships in regulation and pathogenesis“; Böhmer F, Szedlacsek S, Tabernero L, Ostman A, den Hertog J.; FEBS J. 280, 413-31; 2013; DOI: 10.1007/s00253-014-5723-6

13. “Preliminary X-ray crystallographic analysis of the D-xylulose 5-phosphate phosphoketolase from Lactococcus lactis”; Petrareanu, G, Balasu, MC, Zander, U, Scheidig, AJ and Szedlacsek, S.E., Acta Cryst. F66, 805–807; 2010; DOI: 10.1107/S174430911001732X

14. “Interface Analysis of the Complex between ERK2 and PTP-SL”. Balasu MC, Spiridon   LN, Miron S, Craescu CT, Scheidig AJ, Petrescu AJ, Szedlacsek SE. PLoS One. 4(5), e5432; 2009;  DOI: 10.1371/journal.pone.0005432

15. “Analysis of Molecular Determinants of PRL-3”; Pascaru M, Tanase C, Vacaru AM, Boeti P, Neagu E, Popescu I, Szedlacsek SE.;  J Cell Mol Med. 13(9B), 3141-50; 2009; DOI: 10.1111/j.1582-4934.2008.00591.x

16. “Protein tyrosine phosphatases, structure-function relationships”; Tabernero L, Aricescu AR, Jones EY, Szedlacsek SE. FEBS J. 275, 867-82; 2008; DOI: 10.1111/j.1742-4658.2008.06251.x

17. “A microarray strategy for mapping the substrate specificity of protein tyrosine phosphatase”; Köhn M, Gutierrez-Rodriguez M, Jonkheijm P, Wetzel S, Wacker R, Schroeder H, Prinz H, Niemeyer CM, Breinbauer R, Szedlacsek SE, Waldmann H. Angew Chem Int Ed Engl. 46, 7700-3; 2007DOI: 10.1002/anie.200701601

18. “Functional, fractal nonlinear response with application to rate processes with memory, allometry, and population genetics”; Vlad MO, Morán F, Popa VT, Szedlacsek SE, Ross J.; Proc Natl Acad Sci USA., 104, 4798-803; 2007DOI: 10.1073/pnas.0700397104


19. “Identification and specificity profiling of protein prenyltransferase inhibitors using new fluorescent phosphoisoprenoids”; Dursina B, Reents R, Delon C, Wu Y, Kulharia M, Thutewohl M, Veligodsky A, Kalinin A, Evstifeev V, Ciobanu D, Szedlacsek SE, Waldmann H, Goody RS, Alexandrov K. J Am Chem Soc.; 128, 2822-35; 2006; DOI: 10.1021/ja052196e

20. “Fisher's theorems for multivariable, time-and space-dependent systems, with applications in population genetics and chemical kinetics”;  Vlad MO, Szedlacsek SE, Pourmand N, Cavalli- Sforza LL, Oefner P, Ross J; Proc Natl Acad Sci USA; 102, 9848-53; 2005; DOI: 10.1073/pnas.0504073102

21. “The MAM (Meprin/A5-protein/PTPmu) Domain Is a Homophilic Binding Site Promoting  the Lateral Dimerization of Receptor-like Protein-tyrosine Phosphatase μ”; V.B. Cismasiu, S.A. Denes, H. Reilander, H. Michel, and S.E. Szedlacsek;  J. Biol. Chem. 279, 26922-26931; 2004; DOI: 10.1074/jbc.M313115200

22. “Synthesis and biological applications of a new 1,2,5-oxadiazolo[3,4-c]pyridine fluorescent marker”; M.C. Balasu, I. Costea, R. Fratila, A. Popescu, C. Draghici and S.E. Szedlacsek; Rev. Roum. Chim., 49, 309-315; 2004https://doi.org/10.1002/chin.200502149


23. “Protein Tyrosine Phosphatase Inhibitors”; M.C. Balasu and S.E. Szedlacsek; Rev. Chim.; 53, 315- 323; 2002https://www.webofscience.com/wos/woscc/full-record/WOS:000177305200002


24. “Crystal structure of PTP-SL/BR7 catalytic domain, Implications for MAP kinase regulation”; S.E. Szedlacsek, A.R. Aricescu, T.A Fulga, L. Renault, A.J. Scheidig.; J. Mol. Biol.; 311, 557-568; 2001; DOI: 10.1006/jmbi.2001.4890


25. Intramolecular interactions in protein tyrosine phosphatase RPTPμ, Kinetic evidence”;  A.R Aricescu, T.A Fulga, V., Cismasiu, R.S. Goody, S.E. Szedlacsek; Biochem. Biophys. Res. Comm.;  280, 319-327; 2001; DOI: 10.1006/bbrc.2000.4094

26. “Time-dependent control of metabolic systems by external effectors”; S.E. Szedlacsek, A.R. Aricescu, B.H. Havsteen; J. theor. Biol.; 182, 341-350; 1996;  DOI10.1006/jtbi.1996.0173

27. “pH-dependent hysteretic behaviour of human myeloblastin (leucocyte proteinase 3)”; A.  Baici, S.E. Szedlacsek, H. Früh, B.A. Michel; Biochem. J.; 317, 901-905; 1996;  doi: 10.1042/bj3170901

28.  “Esterification of oxysterols by human plasma lecithin cholesterol acyltransferase”; S.E. Szedlacsek, E. Wasowicz, H. Nishida, S.A. Hulea, F. A. Kummerow, T. Nishida, J. Biol. Chem. 270, 11812-11819; 1995DOI10.1074/jbc.270.20.11812

29.  “Kinetics of slow and tight-binding inhibitors”, S.E. Szedlacsek, R.G. Duggleby; Methods Enzymol.; 249, 144-180; 1995DOI10.1016/0076-6879(95)49034-5

30.  ”Steady-state analysis of the reversible closed bicyclic enzyme cascades”; VaronN, R; Havsteen, BH; Szedlacsek, SE; Garcia Moreno, M;  Molina Alarcon, M; Sanchez Gracia, A; Volume: 90, Issue: 1, Pages: 48-53; 1994; DOI10.1016/0020-711x(94)90108-2

31.  “Kinetic analysis of reversible closed bicyclic enzyme cascades covering the whole course of the reaction”; R. Varon, B.H. Havsteen, M. Molina-Alarcon, S.E. Szedlacsek, F. Garcia-Canovas; Int. J. Biochem; 26, 787-797; 1994; DOI10.1016/0020-711x(94)90108-2

32.  “Response coefficients of interconvertible enzyme cascades towards effectors that act on  one or both modifier enzymes”; S. E. Szedlacsek, M.-L. Cardenas, A. Cornish-Bowden, Eur. J. Biochem.;204, 807-813; 1992; DOI: 10.1111/j.1432-1033.1992.tb16699.x

33.  “Egg-white avidin purification by affinity elution from CM-cellulose”; C. Borza, B. Borza, F. Nitu, S. E. Szedlacsek, Rev. Roum. Biochim.;29, 97-99; 1992

34.  “Very large response coefficients in interconvertible enzyme cascades”; A. Cornish-Bowden, S. E. Szedlacsek; Biomed. Biochim. Acta; 49, 829-837; 1990

35.  “Progress-curve equations for reversible enzyme-catalysed reactions inhibited by tight- binding inhibitors”; S.E. Szedlacsek, V. Ostafe, R.G. Duggleby, M. Serban, M.O. Vlad; Biochem. J.;265, 647-653; 1990DOI: 10.1042/bj2650647

36.  “Purification of aprotinin from bovine lung extracts” (in Romanian); H.D. Schell, S.E. Szedlacsek si V. Ostafe; Stud. cercet. Biochim.; 33, 1-82; 1990

Compound for inhibition of certain signaling processes related to the evolution of the cognitive processes 2017-2018
Acronym: Ctr.327/27.03.2017/Company CRU SRL, Medical Services Company/ Dunakesz, Hungary
Project director: Stefan Szedlacsek

The main idea of this project was that by inhibiting at least one of these two interactions of GluA2, the internalization of AMPAR will be reduced and therefore the synapse resistance will be increased, thus leading to improved cognitive functions.

Compound for inhibition of certain signaling processes related to the evolution of the cognitive processes
Novel radiolabeled affibodies for targeted imaging and therapy 2019-2022
Acronym: Bilateral agreement no.3698/13.09.2018 Romanian Academy- Hungarian Academy of Sciences
Project director: Stefan Szedlacsek

The project is agreed as a bilateral collaboration between IBAR and ATOMKI, and the University of Debrecen and IFIN-HH participate in this project voluntarily.

Radiolabelling of affibody for tumor diagnostic and theranostic application in the nuclear medicine 2022-2024
Acronym: Bilateral agreement no.2886/15.09.2021 Romanian Academy- Hungarian Academy of Sciences
Project director: Stefan Szedlacsek

The project is agreed as a joint collaboration among IBAR, ATOMKI and UD, the latter being a cost free participant. There are two main directions envisaged by the proposed project: - receptors mapping and therapy, using an affibody against HER2 receptors, combined with an adequate radioisotope. In this respect, the specific objectives are: a) expression and purification of affibodies; b) establishing labelling procedures; c) ex vivo and/or in vivo testing of optimal compounds.

Biochemical and cellular investigations on the potential use of affibodies in leukemia therapy 2022 - 2023
Acronym: LEUKEMIA. Grant no.779/14.06.2022
Project director: Stefan Szedlacsek

Affibody molecules are highly promising therapeutic candidates due to their advantageous features like: small size, efficient delivery, straightforward engineering towards improved formats, site-directed conjugation of payloads, possibility of GMP production by chemical synthesis or inexpensive bacterial production leading to low product costs.

Biochemical and cellular investigations on the potential use of affibodies in leukemia therapy
Protein Tyrosine Phosphatases: Structure, regulation and biological function 2007 - 2011
Acronym: PTPNET
Budget: Total € 2.965.480/ Cost for IBAR € 145.231
Project director: Stefan Szedlacsek

Project Funded under: Human resources and Mobility in the specific programme for research, technological development and demonstration "Structuring the European Research Area" under the Sixth Framework Programme 2002-2006. PTPNET was a Training Network for young scientists in the field of protein tyrosine phosphatase (PTP) research.

Reconstruction of Ancestor of Receptor Protein Tyrosine Phosphatase Catalytic 2011 - 2016
Acronym: PTPs
Budget: 1.499.990 lei
Project director: Stefan Szedlacsek

Proteins are essential players of all biological processes and they are involved in practically every function performed by a living cell.

Structural insights into three domains of PTP-Basophil-like protein tyrosine phosphatase 01.10.2005 - 30.09.2009
Acronym: PTP-BL
Budget: 50.000 €
Project director: Stefan Szedlacsek

The Alexander von Humboldt Foundation promotes academic cooperation between foreign and German researchers at the highest level. Each year, the Foundation awards more than 700 research fellowships and awards to support researchers from abroad who come to Germany to work on a research project together with German researchers at a host institute. The research topic is chosen by the applicant.

Structural and Kinetic analysis of the functional complex between protein tyrosine phophatase SL (PTP-SL) and Erk2 MAP kinase 2002 -2004 / 2004 - 2008
Acronym: PTP-SL
Budget: 100.000 €
Project director: Stefan Szedlacsek

The Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) is the most important independent research funding organisation in Germany. It supports both scientific and humanistic studies and aims to promote top-level research in various disciplines at universities and research institutions. The main focus is on funding projects proposed by the scientific community, with an emphasis on knowledge-driven research.

Determination of tridimensional structure for some interesting proteins, by X RAY difraction. 2007 - 2010
Acronym: X RAY
Budget: 1.000.000 lei
Project director: Stefan Szedlacsek

Proteins are the most important functional units of living matter: all cellular processes are governed by specific proteins possessing highly specialized functional roles. Understanding the intimate mechanisms of cell functions necessitates a detailed knowledge of the 3D-structure of proteins.

Laboratory for determination of the three-dimensional structure of proteins using x-ray diffraction 2008 – 2010
Budget: 1.428.000 lei
Project director: Stefan Szedlacsek

One of the most powerful techniques in modern biomedical research is the determination of the three dimensional structure of proteins. This project proposes to establish a laboratory for 3D protein structure determination using X-ray diffraction experiments.

Evaluation of the substrate specificity of several protein tyrosine phosphatases involved in diseases 2008 – 2010
Budget: Total 2.000.000 lei/ Cost for IBAR: 1.700.000 lei
Project director: Stefan Szedlacsek

Protein tyrosine phosphatases (PTPs) are fundamental regulatory enzymes that dephosphorylate phosphotyrosine residues and are essential components of intracellular signalling pathways in both normal and pathological conditions. There is experimental evidence that disruption of the phosphatase activity of many PTPases is involved in the pathogenesis of several congenital or acquired diseases, including diabetes, cancer, infections, autoimmune, neuronal and cardiovascular diseases.

Enzymatic caracterization and identification of potential native substrates for Eyes absent, protein responsible for Branchio-Oto-Renal syndrome 2006 - 2008
Acronym: BOR
Budget: 247.294 lei
Project director: Stefan Szedlacsek

The project focuses on characterizing the branchio-oto-renal (BOR) syndrome, an autosomal dominant genetic disorder caused by mutations in the EYA gene. The goal is to enzymatically analyze the conserved C-terminal domain of the Eya3 protein and identify physiological substrates to better understand the molecular mechanisms involved in this syndrome.

Molecular Analysis of Protein Tyrosine Phosphatase Involvement PRL-3 in Metastasis of Colorectal Cancer 2004-2006
Budget: Total 500.000 lei / Cost for IBAR: 300.000 lei
Project director: Stefan Szedlacsek

Cancer causes 1.5 million deaths a year in Europe, accounting for a quarter of all deaths. The incidence of cancer is increasing, with 20 million new cases and 10 million deaths expected in the next 20 years. Approximately 90% of deaths are due to metastases rather than primary tumours. Genetic mutations and genomic instability allow tumour cells to invade and form metastases.

Molecular optimization of a central enzyme in the metabolic pathway of the xylose conversion. Optimized reactor for the enzymatic transformation of the xylose originating from cellulosic wastes. 2005-2008
Acronym: OMEXIL
Budget: Total 1.712.800 lei/ Cost for IBAR: 1.298.000 lei
Project director: Stefan Szedlacsek

This project aims to develop a highly efficient enzyme for the conversion of xylose from cellulosic wastes into high-value biosynthetic intermediates. By optimising the catalytic efficiency of phosphoketolase and designing an enzymatic reactor, the project aims to provide a sustainable method of utilising lignocellulosic residues.