Cover Page

Contents

Cover

Titles of the Series “Drug Discovery in Infectious Diseases”

Title Page

Copyright

Foreword

Acknowledgment

Preface

List of Contributors

Part One: Disease Burden, Current Treatments, Medical Needs, and Strategic Approaches

Chapter 1: Visceral Leishmaniasis – Current Treatments and Needs

Introduction

Current Anti-Leishmanial Drugs and Treatment Options for Visceral Leishmaniasis

PKDL

Open Questions and Needs

References

Chapter 2: Chemotherapy of Leishmaniasis: A Veterinary Perspective

Introduction

Chemotherapy of Canine Leishmaniasis

Exploration of New Anti-Leishmanial Drugs

Concluding Remarks

Acknowledgments

References

Chapter 3: Pharmacological Metabolomics in Trypanosomes

Introduction

Metabolomics – New Technologies Applied to Trypanosomes

Metabolic Affects of Trypanocidal Drugs

Conclusion

Acknowledgments

References

Chapter 4: Drug Design and Screening by In Silico Approaches

Introduction

Computer-Aided Drug Design: General Remarks

Supercomputers and Other Technical Resources

Molecular Modeling and Anti-Kinetoplastida Drug Design

Ligand-Based Approaches Against Trypanosoma Parasites

Structure-Based Drug Design and Screening

Virtual Screening Approaches against Trypanosome Proteins

In Silico Prediction of Protein Druggability

References

Chapter 5: Computational Approaches and Collaborative Drug Discovery for Trypanosomal Diseases

Introduction

CDD Database

Using HTS Data for Machine Learning Models

Discussion

Acknowledgments

References

Part Two: Metabolic Peculiarities in the Trypanosomatid Family Guiding Drug Discovery

Chapter 6: Interaction of Leishmania Parasites with Host Cells and its Functional Consequences

Life Cycle of Leishmania

Host Cells of Leishmania

DCs

Conclusion

References

Chapter 7: Function of Glycosomes in the Metabolism of Trypanosomatid Parasites and the Promise of Glycosomal Proteins as Drug Targets

Introduction

Glycosomes of T. brucei

Glycosomes of T. cruzi

Glycosomes of Leishmania spp.

Essentiality of Controlled Communication Across the Glycosomal Membrane

Essentiality of Correct Integration of Glycosomal Metabolism in the Overall Metabolism – Relation to Life Cycle Differentiation

What Has Been Achieved So Far in Target Characterization?

What Has Been Achieved So Far in the Development of Inhibitors of Glycosomal Enzymes or Processes

Discussion and Conclusions

Acknowledgments

References

Chapter 8: Glyoxalase Enzymes in Trypanosomatids

Glyoxalase Pathway

Glyoxalase I

Glyoxalase II

Glyoxalase Pathway Regulation

Glyoxalase Pathway as a Therapeutic Target

Conclusion

References

Chapter 9: Trypanothione-Based Redox Metabolism of Trypanosomatids

Thiol Redox Metabolism of Trypanosomatids: A Brief Historical Overview

Trypanothione Biosynthesis

Trypanothione Recycling

Trypanothione Utilization

Conclusions

Acknowledgments

References

Chapter 10: Thiol Peroxidases of Trypanosomatids

Thiol-Dependent Peroxidases in Trypanosomatids

Mechanism of Reaction of Thiol Peroxidases

Trypanosomatid PRXs

Trypanosomatid GPXs

Function of Thiol Peroxidases in Trypanosomatids

Conclusions

References

Chapter 11: Peroxynitrite as a Cytotoxic Effector Against Trypanosoma cruzi: Oxidative Killing and Antioxidant Resistance Mechanisms

Introduction

Peroxynitrite Formation During T. cruzi–Mammalian Host Cell Interaction

Peroxynitrite Diffusion and Reactivity with T. cruzi Targets

Peroxynitrite Detoxification Systems

T. cruzi Antioxidant Enzymes as Virulence Mediators

Conclusions

Acknowledgments

References

Chapter 12: Selenoproteome of Kinetoplastids

Introduction

Kinetoplastid Selenoproteome

Selenoproteome is Dispensable

Selenoproteome is Relevant for Long-Term Protection

Conclusions

References

Chapter 13: Replication Machinery of Kinetoplast DNA

Introduction: kDNA Network and its Monomeric Subunits

Replication of kDNA Minicircles, Maxicircles, and Networks

Components of the kDNA Replication Machinery: Replication Proteins and Complexes

Regulation of kDNA Replication

Conclusion: kDNA Replication Machinery as an Anti-Trypanosomal Drug Target

Acknowledgments

References

Chapter 14: Life and Death of Trypanosoma brucei: New Perspectives for Drug Development

Necrosis

Autophagic Cell Death

Apoptosis in Protozoan Parasites

Outlook

References

Part Three: Validation and Selection of Drug Targets in Kinetoplasts

Chapter 15: Rational Selection of Anti-Microbial Drug Targets: Unique or Conserved?

Introduction

Phosphodiesterases

Ergosterol Synthesis

N-Myristoyl Transferase

Proteases

Kinases

Concluding Remarks

References

Chapter 16: Drug Targets in Trypanosomal and Leishmanial Pentose Phosphate Pathway

Pentose Phosphate Pathway in Trypanosomatids: General Considerations and Biological Relevance

Biochemical and Structural Hallmarks of Trypanosomatids PPP Enzymes

Inhibitor Discovery Against PPP Enzymes

Conclusions

Acknowledgments

References

Chapter 17: GDP-Mannose: A Key Point for Target Identification and Drug Design in Kinetoplastids

Introduction

Comparison of Mannosylation Pathways between Mammals and Kinetoplastids

Enzymes and Transporters Involved in Mannosylation in Mammals and Kinetoplastids

Conclusion

References

Chapter 18: Transporters in Anti-Parasitic Drug Development and Resistance

Introduction

“Rule of Five”

Diffusion

Selective Uptake by Protozoan Transporters

Role of Efflux Transporters

Diagnosing Drug Resistance Through Screening of Transporter Mutations: T. congolense as an Example

Concluding Remarks

References

Chapter 19: Peptidases in Autophagy are Therapeutic Targets for Leishmaniasis

Introduction

Molecular Machinery for Autophagosome Biogenesis

ATG4 Regulates the Autophagic Pathway of Leishmania spp.

Leishmania's Cathepsins Regulates Autophagy and Virulence

Other Possible Peptidase Targets

Cysteine Peptidase Inhibitors: Opportunities and Challenges

Conclusions and Future Directions

Acknowledgments

References

Chapter 20: Proteases of Trypanosoma brucei

Introduction

Classes of Proteases

Cellular Functions

Proteases as Drug Targets

Conclusion

References

Part Four: Examples of Target-Based Approaches and Compounds Under Consideration

Chapter 21: Screening Approaches Towards Trypanothione Reductase

Introduction

Unique Thiol Redox Metabolism of Trypanosomatids as a Target Area for Future Drug Development

Screening Approaches Towards TR

Combined In Vitro/In Silico Screening Campaign

Conclusion

References

Chapter 22: Redox-Active Agents in Reactions Involving the Trypanothione/Trypanothione Reductase-based System to Fight Kinetoplastidal Parasites

Introduction

TR as a Drug Target Molecule

Turncoat Inhibitors (Subversive Substrates or Redox Cyclers) of TR as Anti-Trypanosomal Drugs

1,4-NQs as Trypanocidal Agents

Nitrofurans

Other Subversive Substrates

Trypanothione-Reactive Agents (Susceptible to Enter Redox Cycling Following Double Michael Addition) as Anti-Trypanosomal Drugs

Conclusions

Acknowledgments

References

Chapter 23: Inhibition of Trypanothione Synthetase as a Therapeutic Concept

Introduction

Functional and Structural Characteristics of TryS

TryS Inhibitor Design

Conclusions

References

Chapter 24: Targeting the Trypanosomatidic Enzymes Pteridine Reductase and Dihydrofolate Reductase

Introduction

X-Ray Crystal Structures of DHFR and PTR1

Discovery and Development of PTR1 Inhibitors

Inhibition of DHFR

Conclusions and Perspectives

References

Chapter 25: Contribution to New Therapies for Chagas Disease

Introduction

Current Therapy

Targeting the T. cruzi Protease Cruzain

Why is Cruzain a Good Drug Target?

Other Potent Cruzain Inhibitors

Targeting Ergosterol Biosynthesis

Why Multiple Targets?

Development of Drug Screening Methods

Conclusions

Acknowledgements

References

Chapter 26: Ergosterol Biosynthesis for the Specific Treatment of Chagas Disease: From Basic Science to Clinical Trials

Introduction

Currently Available Drugs for the Specific Treatment of Chagas Disease: Limitations and Controversies on their Application

EBIs as Potential New Therapeutic Agents for Chagas Disease

Conclusions

References

Chapter 27: New Developments in the Treatment of Late-Stage Human African Trypanosomiasis

Introduction

Life Cycle of T. b. brucei

Current Chemotherapy

Need for New Chemotherapy

Recent Approaches to New Trypanocidal Agents

Conclusion

References

Index

Titles of the Series “Drug Discovery in Infectious Diseases”

Selzer, P. M. (ed.)

Antiparasitic and Antibacterial Drug Discovery

From Molecular Targets to Drug Candidates

2009

ISBN: 978-3-527-32327-2

Becker, K. (ed.)

Apicomplexan Parasites

Molecular Approaches toward Targeted Drug Development

2011

ISBN: 978-3-527-32731-7

Conor R. Caffrey (ed.)

Parasitic Helminths

Targets, Screens, Drugs and Vaccines

2012

ISBN 978-3-527-33059-1

Forthcoming Topics of the Series

Related Titles

Lucius, R., Loos-Frank, B., Grencis, R. K., Striepen, B., Poulin, R. (eds.)

The Biology of Parasites

2014

ISBN: 978-3-527-32848-2

Lamb, T.

Immunity to Parasitic Infections

2013

ISBN: 978-0-470-97247-2

Zajac, A. M., Conboy, G. A. (eds.)

Veterinary Clinical Parasitology

2012

ISBN: 978-0-8138-2053-8

Scott, I., Sutherland, I.

Gastrointestinal Nematodes of Sheep and Cattle

Biology and Control

2009

ISBN: 978-1-4051-8582-0.

Title Page

Foreword

Drug Discovery for Neglected Diseases – Past and Present and Future

The kinetoplastid diseases – sleeping sickness, the leishmaniases, and Chagas disease – are “neglected diseases of poverty,” afflicting millions of people and collectively responsible for over 100 000 deaths per annum. No vaccines are available and current insect vector control methods and other public health measures are insufficient to eliminate them. The currently available drug therapies are far from satisfactory due to issues such as poor efficacy, toxicity, the need for hospitalization, the requirement for prolonged parenteral treatment, and high cost. This book is a timely attempt to address some of these unmet medical needs.

It is somewhat ironic that, at the beginning of the twentieth century, many of the ground-breaking developments in drug discovery were driven by economic and colonial expansion in Africa and Asia. The African trypanosome in particular was an early model for experimental chemotherapy along two main lines of investigation: synthetic dyes, and organic arsenicals and antimonials (for further details, see reviews by Williamson [1] and Steverding [2]). Indeed, the first synthetic compound to cure an infectious disease in an animal model was the dye, Trypan red (Ehrlich, 1904), which was a forerunner of suramin (1916–1920), the first effective trypanocidal drug for human African trypanosomiasis (HAT). The demonstration by Thomas and Breinl in 1905 of the trypanocidal activity in mice of atoxyl (p-aminophenylarsonic acid) formed the basis of Ehrlich's pioneering work on organic arsenicals that culminated in the development of arsphenamine (606, Salvarsan) for the treatment of syphilis (Ehrlich and Hata, 1910) and tryparsamide for the treatment of HAT (Jacobs and Heidelberger, 1919). Tryparsamide, which caused blindness in 10–20% of patients, was finally replaced by melarsoprol (Friedheim, 1949). Trivalent antimony, in the form of tartar emetic, was shown to be trypanocidal in mice (Plimmer and Thompson, 1908), but lacked efficacy in humans. However, potassium antimony tartrate was found to have some activity in the treatment of leishmaniasis (Vianna, 1912) and was the forerunner of the pentavalent antimonial drugs, sodium stibogluconate (Pentostam®) and meglumine antimonate (Glucantime®), both introduced in the 1940s. Along with the diamidine, pentamidine (1937), all of these drugs are still in use today.

From the 1950s, subsequent drug treatments have largely been discovered by serendipity through repurposing of existing drugs used for other indications. The nitrofuran, nifurtimox, and the nitroimidazole, benznidazole, used for the treatment of Chagas disease arose from research into nitro-compounds as antibacterial agents. Amphotericin B, isolated in 1953, was originally developed for the treatment of systemic mycoses, but later found use in the treatment of visceral leishmaniasis in the 1990s as the expensive, but highly efficacious liposomal formulation (AmBisome®) or as the cheaper, but more toxic amphotericin B deoxycholate. Both formulations were included in the World Health Organization's Essential Medicines List in 2009. The off-patent aminoglycoside, paromomycin, originally developed as an oral treatment for intestinal infections in the 1960s, finally gained approval as paromomycin intramuscular injection for the treatment of visceral leishmaniasis in India in 2006. Two anticancer agents, the phospholipid analog, miltefosine, registered as the first oral treatment for visceral leishmaniasis in India in 2002, and eflornithine (now in combination with oral nifurtimox as nifurtimox–eflornithine combination therapy (NECT), 2009) for the treatment of HAT caused by Trypanosoma brucei gambiense complete the woefully inadequate treatment options for these diseases. Notably, none of these newer developments have completely displaced their forerunners that were developed prior to the 1950s.

After nearly a century of research, only 10 novel chemical entities for three diseases is a singularly unimpressive output by the pharmaceutical industry. The reason for this lamentable performance is not hard to find. Poor economic return on investment by pharma is a major factor, since these are diseases of poverty. The thalidomide disaster of the late 1950s kick-started regulatory demands for greater patient safety resulting in ever-increasing development costs. Blockbuster drugs were “in;” smaller, less profitable markets were “out.” Ninety percent of research and development was aimed at 10% of the world's unmet medical need – the so-called “10–90 gap.” The drive for greater efficiency and profitability through mergers and acquisitions resulted in the loss of parasitology expertise in most pharma companies. Medicinal chemists were seduced by combinatorial chemistry without due regard for chemical space and drug-likeness. Miniaturization of chemical synthesis restricted the use of animal disease models and shifted emphasis towards target screening. Intellectual property rights were increasingly used as an obstructive, rather than an enabling tool.

At the end of the twentieth century, the situation had become so dire that a radical new approach was required. One of the most encouraging developments was the founding of “public–private partnerships” (PPPs), such as the Drugs for Neglected Diseases initiative (DNDi) and Medicines for Malaria Venture (MMV) – non-profit organizations who strive to forge drug discovery partnerships between multiple academic, biotech, and pharma partners with funding from the governmental and charitable sector [3]. PPPs were initially met with much skepticism, but by 2005, an analysis by Mary Moran and colleagues concluded that PPPs were responsible for three-quarters of an expanded research and development portfolio for neglected diseases [4]. Another important development was the publication of annotated genomes for T. brucei, L. major, and T. cruzi in 2005 [5–7]. As Barry Bloom optimistically prophesized 10 years earlier “Sequencing bacterial and parasitic pathogens . . . could buy the sequence of every virulence determinant, every protein antigen and every drug target . . . for all time” [8]. Certainly, pathogen genomes are proving to be a valuable resource for target discovery, but without a deeper understanding of parasite biology the full potential of these genomes will not be realized. About the same time as genome sequencing was getting underway, C.C. Wang threw down the gauntlet that academics needed genetic evidence of essentiality to justify their claims of the therapeutic potential of their research field [9]. This dogma has now been refined and extended to include chemical evidence of druggability, driven by a defined therapeutic product profile [10]. These challenges have encouraged some academics to move out of their traditional comfort zones to fill the early-stage drug discovery gap in translational medicine not adequately covered by the PPPs [11]. The concept of “one gene, one target, one drug” has been very much at the forefront of current academic (and industry) thinking, with structure-based design an important adjunct in this strategy. Thus, it is timely that much of this book is devoted to the identification of metabolic peculiarities in the kinetoplastids that can be chemically and genetically validated as drug targets.

However, what of the future? Experience in industry and in academia suggests that the rate of validation of new targets is failing to keep pace with the rate of attrition of currently validated targets. Despite initial promise, the target-based approach has yielded disappointing results in anti-bacterial discovery in pharma [12] and lessons need to be learned from this if we are to avoid making the same mistakes. Rapid and robust methods of genetic target validation are still needed for parasites causing visceral leishmaniasis and Chagas disease, and we need a better understanding of basic biology to understand why targets fail. Certainly, not all targets are equal from a medicinal chemistry point of view. Greater attention needs to be paid to drug likeness [13] and ligand efficiency [14] for lead selection. Screening of fragment libraries using biophysical methods should help to weed out “undruggable” targets without recourse to expensive high-throughput screens [15]. From a pharmacology perspective, cytocidal activity is much preferable to cytostatic, so biologists should address this question early in discovery. Likewise, the potential ease for resistance arising as a result of point mutations in a single-target strategy should be a research priority for biologists. Systems biology suggests that exquisitely selective, single-target compounds may exhibit lower than desired clinical efficacy compared with multitarget drugs due to the robustness of biological networks [16]. Thus, polypharmacology (network pharmacology) is undergoing a resurgence of interest. Given the paucity of validated druggable targets, phenotypic screening is undergoing a revival aided by access to large compound collections held by pharma and the development of suitable miniaturized whole-parasite screens and mammalian counter-screens. This approach has the advantage of addressing the key druggability issues of cell permeability, desirable cytocidal activity, and a suitable parasite–host selectivity window. Phenotypic screening can also identify compounds hitting non-protein targets (e.g., amphotericin B) or compounds that act as pro-drugs (e.g., nitroimidazoles). However, the future challenge will be to identify the often complex mode(s) of action of such phenotypic hits (target deconvolution), and to use modern technologies to improve the potency and selectivity of these molecules [17]. Finally, we should ask ourselves whether our compound collections are too “clean” in terms of chemical reactivity. After all, arsenicals, antimonials, nitro-drugs, and eflornithine all undergo reaction with one or more targets, and about one-quarter of all drugs that inhibit enzymes are essentially irreversible reactions [18].

I believe that there is every cause for optimism in the battle against neglected diseases. As long as “donor fatigue” does not set in, and industry continues to engage in a positive and productive manner with academia, future prospects look better than at any time in history. However, we should all remember the dictum by Sir James Black “to first purge your project of wishful thinking” if we are to succeed!

Dundee, UK

Alan Fairlamb

References

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6. Ivens, A.C., Peacock, C.S., Worthey, E.A., Murphy, L., Aggarwal, G., Berriman, M., Sisk, E., Rajandream, M.A., Adlem, E., Aert, R., Anupama, A., Apostolou, Z., Attipoe, P., Bason, N., Bauser, C., Beck, A., Beverley, S.M., Bianchettin, G., Borzym, K., Bothe, G., Bruschi, C.V., Collins, M., Cadag, E., Ciarloni, L., Clayton, C., Coulson, R.M., Cronin, A., Cruz, A.K., Davies, R.M., De Gaudenzi, J., Dobson, D.E., Duesterhoeft, A., Fazelina, G., Fosker, N., Frasch, A.C., Fraser, A., Fuchs, M., Gabel, C., Goble, A., Goffeau, A., Harris, D., Hertz-Fowler, C., Hilbert, H., Horn, D., Huang, Y., Klages, S., Knights, A., Kube, M., Larke, N., Litvin, L., Lord, A., Louie, T., Marra, M., Masuy, D., Matthews, K., Michaeli, S., Mottram, J.C., Muller-Auer, S., Munden, H., Nelson, S., Norbertczak, H., Oliver, K., O'neil, S., Pentony, M., Pohl, T.M., Price, C., Purnelle, B., Quail, M.A., Rabbinowitsch, E., Reinhardt, R., Rieger, M., Rinta, J., Robben, J., Robertson, L., Ruiz, J.C., Rutter, S., Saunders, D., Schafer, M., Schein, J., Schwartz, D.C., Seeger, K., Seyler, A., Sharp, S., Shin, H., Sivam, D., Squares, R., Squares, S., Tosato, V., Vogt, C., Volckaert, G., Wambutt, R., Warren, T., Wedler, H., Woodward, J., Zhou, S., Zimmermann, W., Smith, D.F., Blackwell, J.M., Stuart, K.D., Barrell, B., and Myler, P.J. (2005) The genome of the kinetoplastid parasite, Leishmania major. Science, 309, 436–442.

7. El-Sayed, N.M., Myler, P.J., Bartholomeu, D.C., Nilsson, D., Aggarwal, G., Tran, A.N., Ghedin, E., Worthey, E.A., Delcher, A.L., Blandin, G., Westenberger, S.J., Caler, E., Cerqueira, G.C., Branche, C., Haas, B., Anupama, A., Arner, E., Aslund, L., Attipoe, P., Bontempi, E., Bringaud, F., Burton, P., Cadag, E., Campbell, D.A., Carrington, M., Crabtree, J., Darban, H., da Silveira, J.F., de Jong, P., Edwards, K., Englund, P.T., Fazelina, G., Feldblyum, T., Ferella, M., Frasch, A.C., Gull, K., Horn, D., Hou, L.H., Huang, Y.T., Kindlund, E., Ktingbeil, M., Kluge, S., Koo, H., Lacerda, D., Levin, M.J., Lorenzi, H., Louie, T., Machado, C.R., McCulloch, R., McKenna, A., Mizuno, Y., Mottram, J.C., Nelson, S., Ochaya, S., Osoegawa, K., Pai, G., Parsons, M., Pentony, M., Pettersson, U., Pop, M., Ramirez, J.L., Rinta, J., Robertson, L., Salzberg, S.L., Sanchez, D.O., Seyler, A., Sharma, R., Shetty, J., Simpson, A.J., Sisk, E., Tammi, M.T., Tarteton, R., Teixeira, S., Van Aken, S., Vogt, C., Ward, P.N., Wickstead, B., Wortman, J., White, O., Fraser, C.M., Stuart, K.D., and Andersson, B. (2005) The genome sequence of Trypanosoma cruzi, etiologic agent of Chagas disease. Science, 309, 409–415.

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Acknowledgment

This publication is supported by COST.

COST – the acronym for European Cooperation in Science and Technology – is the oldest and widest European intergovernmental network for cooperation in research. Established by the Ministerial Conference in November 1971, COST is presently used by the scientific communities of 36 European countries to cooperate in common research projects supported by national funds.

The funds provided by COST – less than 1% of the total value of the projects – support the COST cooperation networks (COST Actions) through which, with EUR 30 million per year, more than 30 000 European scientists are involved in research having a total value which exceeds EUR 2 billion per year. This is the financial worth of the European added value which COST achieves.

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Preface

Infections caused by parasites of the trypanosomatid family are considered to belong to the most neglected diseases. They comprise the African sleeping sickness (Trypanosoma brucei rhodesiense, T. brucei gambiense), the Chagas' disease in Latin America (T. cruzi), the black fever or Kala-Azar (Leishmania donovani) and other forms of Leishmaniasis (various Leishmania species). They affect about 30 million of people and account for half a million of fatalities per year. Trypanosomatids also cause substantial economic losses by affecting life stock (T. brucei brucei, T. congolense, T. evansi). Available treatments of the diseases are unsatisfactory in terms of safety and efficacy. Industrial commitments to meet the therapeutic needs remain limited because of unfavourable economic perspectives for drugs acting on diseases that prevail in countries with poor socio-economic conditions. In fact, currently used drugs are overwhelmingly those developed many decades ago when the ‘Western World’ had still to be concerned about the health of administrators and soldiers in their tropical colonies.

The present book originates from an interdisciplinary network of academic and industrial researchers devoted to the development of “new drugs for neglected diseases”. The initiative was sponsored by the European Union (COST Action CM0801) and in the beginnings was largely restricted to Europe. Over the four years of its operation, however, the exchange of experience and cooperative projects expanded far beyond its geographical basis, particularly by integrating countries in Latin America, Africa and Asia where the diseases are endemic. The progress achieved by this network is reflected in many of the contributions to the book. The editors, however, took care not just to present a ‘progress report’ but the state-of-the-art in the entire field of drug discovery for trypanosomatid diseases, as reviewed by leading scientists from all over the world. It is hoped that the compiled knowledge will become instrumental to shorten the time from basic discoveries to the urgently needed new drugs for the neglected diseases.

The editor's heartfelt thanks go to the contributing authors for their excellent work, to the series editor Paul M. Selzer for his constructive advice, and to the COST Office in Brussels for financial support.

Braunschweig, Ingelheim, Potsdam, Germany
March 2013

Timo Jäger
Oliver Koch
Leopold Flohé

List of Contributors

José María Alunda1

Universidad Complutense

Department of Animal Health

Faculty of Veterinary Medicine

Avenida Puerta de Hierro s/n

28040 Madrid

Spain

jmalunda@ucm.es

María Noel Alvarez

Departamento de Bioquímica and

Center for Free Radical and

Biomedical Research

Facultad de Medicina

Universidad de la República

Avenida General Flores 2125

11800 Montevideo

Uruguay

Luisana Avilán

Universidad de los Andes

Laboratorio de Fisiología

Facultad de Ciencias

La HechiceraAv. Alberto Carnevalli

Mérida 5101

Venezuela

Cyrus J. Bacchi

Pace University

The Haskins Laboratories

41 Park Row

New York, NY 10038

USA

Michael P. Barrett1

University of Glasgow

Wellcome Trust Centre for Molecular Parasitology

Institute of Infection, Immunity and Inflammation

College of Medical, Veterinary and Life Sciences

120 University Place

Glasgow G12 8TA

UK

michael.barrett@glasgow.ac.uk

Torsten Barth

Eberhard Karls Universität Tübingen

Interfakultäres Institut für Biochemie

Hoppe-Seyler-Strasse 4

72076 Tübingen

Germany

torsten.barth@uni-tuebingen.de

Mathias Beig

MSD Animal Health Innovation GmbH

Zur Propstei

55270 Schwabenheim

Germany

Rachel Bezalel-Buch

The Hebrew University-Hadassah Medical School

Department of Microbiology and Molecular Genetics

Kuvin Center for the Study of Infectious and Tropical Diseases

Institute for Medical Research Israel–Canada

PO Box 12272

Jerusalem 91120

Israel

Maurizio Botta1

University of Siena

Faculty of Pharmacy

Via Aldo Moro 2

53100 Siena

Italy

botta.maurizio@gmail.com

Barry A. Bunin

Collaborative Drug Discovery, Inc.

1633 Bayshore Highway Suite 342

Burlingame, CA 94010

USA

Ana J. Cáceres

Universidad de los Andes

Laboratorio de Enzimología de Parásitos

Facultad de Ciencias

La HechiceraAv. Alberto Carnevalli

Mérida 5101

Venezuela

Helena Castro1

Universidade do Porto

Instituto de Biologia Molecular e Celular

Rua do Campo Alegre 823

4150-180 Porto

Portugal

hcastro@ibmc.up.pt

Juan José Cazzulo

Universidad Nacional General San Martín/CONICET

Instituto de Investigaciones Biotecnológicas (IIB/INTECH)

Campus Miguelete

Avenida 25 de Mayo y Francia

1650 San Martín

Buenos Aires

Argentina

jcazzulo@iibintech.com.ar

Marcelo A. Comini1

Institut Pasteur de Montevideo

Group Redox Biology of Trypanosomes

Mataojo 2020

11400 Montevideo

Uruguay

mcomini@pasteur.edu.uy

Juan-Luis Concepción

Universidad de los Andes

Laboratorio de Enzimología de Parásitos

Facultad de Ciencias

La Hechicera

Av. Alberto Carnevalli

Mérida 5101

Venezuela

Carlos Cordeiro1

Universidade de Lisboa

Faculdade de Ciências

Departamento de Química e Bioquímica

Centro de Química e Bioquímica

Edifício C8 Campo Grande

1749-016 Lisboa

Portugal

cacordeiro@fc.ul.pt

María Jesús Corral-Caridad

Universidad Complutense

Department of Animal Health

Faculty of Veterinary Medicine

Avenida Puerta de Hierro s/n

28040 Madrid

Spainmariajco@ucm.es

Maria Paola Costi1

University of Modena and Reggio Emilia

Department of Life Science

Via Campi 183

41125 Modena

Italy

mariapaola.costi@unimore.it

Darren J. Creek

University of Glasgow

Wellcome Trust Centre for Molecular Parasitology

Institute of Infection, Immunity and Inflammation

College of Medical, Veterinary and Life Sciences

120 University Place

Glasgow G12 8TA

UK

and

University of Melbourne

Department of Biochemistry and Molecular Biology

Bio21 Molecular Science and Biotechnology Institute

Flemington Road

Parkville

Victoria 3010

Australia

Elisabeth Davioud-Charvet1

UMR CNRS 7509

European School of Chemistry, Polymers and Materials (ECPM)

Bioorganic and Medicinal Chemistry

25 rue Becquerel

67087 Strasbourg Cedex 2

France

elisabeth.davioud@unistra.fr

Harry P. de Koning1

University of Glasgow

Institute of Infection

Immunity and Inflammation

College of Medical

Veterinary and Life Sciences

120 University Place

Glasgow G12 8TA

UK

Harry.de-Koning@glasgow.ac.uk

Vincent Delespaux

Institute of Tropical Medicine Antwerpen

Department of Biomedical Sciences

Nationalestraat 155

2000 Antwerp

Belgium

Patricia S. Doyle1

University of California San Francisco

Department of Pathology and Sandler Center for Drug Discovery

1700 4th Street 508

San Francisco, CA 94158-2330

USA

patricia.doyle.engel@gmail.com

Michael Duszenko1

Eberhard Karls Universität Tübingen

Interfakultäres Institut für Biochemie

Hoppe-Seyler-Strasse 4

72076 Tübingen

Germany

michael.duszenko@uni-tuebingen.de

Sean Ekins1

Collaborative Drug Discovery, Inc.

1633 Bayshore Highway Suite 342

Burlingame, CA 94010

USA

sekins@collaborativedrug.com

and

Collaborations in Chemistry

5616 Hilltop Needmore Road

Fuquay Varina, NC 27526

USA

and

University of Maryland

Department of Pharmaceutical Sciences

20 North Pine Street

Baltimore, MD 21201

USA

and

University of Medicine & Dentistry of New Jersey (UMDNJ)

Robert Wood Johnson Medical School

Department of Pharmacology

675 Hoes lane

Piscataway, NJ 08854

USA

Juan C. Engel

University of California San Francisco

Department of Pathology and Sandler Center for Drug Discovery

1700 4th Street 508

San Francisco, CA 94158-2330

USA

juan.engel@ucsd.edu

Alan Fairlamb1

Division of Biological Chemistry & Drug Discovery

College of Life Sciences

University of Dundee

Dundee DD1 5EH

UK

a.h.fairlamb@dundee.ac.uk

Stefania Ferrari

University of Modena and Reggio Emilia

Department of Life Science

Via Campi 183

41125 Modena

Italy

António E.N. Ferreira

Universidade de Lisboa

Faculdade de Ciências

Departamento de Química e Bioquímica

Centro de Química e Bioquímica

Edifício C8 Campo Grande

1749-016 Lisboa

Portugal

Leopold Flohé

Otto-von-Guericke-Universität Magdeburg

Chemisches Institut

Universitätsplatz 2

39106 Magdeburg

Germany

Thibault Gendron

UMR CNRS 7509

European School of Chemistry, Polymers and Materials (ECPM)

Bioorganic and Medicinal Chemistry

25 rue Becquerel

67087 Strasbourg Cedex 2

France

Vadim N. Gladyshev1

Harvard Medical School

Division of Genetics

Department of Medicine

Brigham and Women's Hospital

75 Francis Street

Boston, MA 02115

USA

vgladyshev@rics.bwh.harvard.edu

Ricardo Gomes

Universidade de Lisboa

Faculdade de Ciências

Departamento de Química e Bioquímica

Centro de Química e Bioquímica

Edifício C8 Campo Grande

1749-016 Lisboa

Portugal

Melisa Gualdrón-López

Université catholique de Louvain

Research Unit for Tropical Diseases

de Duve Institute

Avenue Hippocrate 74

La Hechicera

Av. Alberto Carnevalli

1200 Brussels

Belgium

Martín Hugo

Departamento de Bioquímica and

Center for Free Radical and Biomedical Research

Facultad de Medicina

Universidad de la República

Avenida General Flores 2125

11800 Montevideo

Uruguay

Robert T. Jacobs

Scynexis, Inc.

PO Box 12878

Research Triangle Park NC 27709-2878

USA

Timo Jäger

German Centre for Infection Research (DZIF)

Inhoffenstraße 7

38124 Braunschweig

Germany

timo.jaeger@dzif.de

Oliver Koch1

Junior Research Group Leader “Medicinal Chemistry”

Chemical Biology – Faculty of Chemistry

Technische Universität Dortmund

Otto-Hahn-Straße 6

44227 Dortmund

Oliver.Koch@tu-dortmund.de

R. Luise Krauth-Siegel

Heidelberg University

Biochemistry Center

Im Neuenheimer Feld 328

69120 Heidelberg

Germany

Bruno K. Kubata

Research for Health Africa & Pharma Innovation

AU/NEPAD Agency Regional Office in Nairobi

C/o the AU/Inter African Bureau for Animal Resources

P.O. BOX 13601-00800

Kenya

brunokubata@yahoo.com

Don Antoine Lanfranchi

UMR CNRS 7509

European School of Chemistry, Polymers and Materials (ECPM)

Bioorganic and Medicinal Chemistry

25 rue Becquerel

67087 Strasbourg Cedex 2

France

Alexei V. Lobanov

Harvard Medical School

Division of Genetics

Department of Medicine

Brigham and Women's Hospital

75 Francis Street

Boston, MA 02115

USA

Philippe M. Loiseau

Université Paris-Sud 11

Faculté de Pharmacie

UMR 8076 CNRS

Chimiothérapie Antiparasitaire

5 rue Jean-Baptiste Clément

92290 Châtenay-Malabry

France

Valeria Losasso

University of Modena and Reggio Emilia

Department of Life Science

Via Campi 183

41125 Modena

Italy

and

Scientific Computing Department, Science and Technology Facilities Council

Daresbury Laboratory

Keckwick Lane

Warrington WA4 4AD

UK

Anita Masic

University of Würzburg

Institute for Molecular Infection Biology

Josef-Schneider-Strasse 2/D15

97080 Würzburg

Germany

Paul A.M. Michels1

Université catholique de Louvain

Research Unit for Tropical Diseases

de Duve Institute

Avenue Hippocrate 74

1200 Brussels

Belgium

paul.michels@uclouvain.be

Stefan Mogk

Eberhard Karls Universität Tübingen

Interfakultäres Institut für Biochemie

Hoppe-Seyler-Strasse 4

72076 Tübingen

Germany

labor@virtualmogk.de

Heidrun Moll1

University of Würzburg

Institute for Molecular Infection Biology

Josef-Schneider-Strasse 2/D15

97080 Würzburg

Germany

heidrun.moll@uni-wuerzburg.de

Mattia Mori

University of Siena

Faculty of Pharmacy

Via Aldo Moro 2

53100 Siena

Italy

Frank Oellien

MSD Animal Health Innovation GmbH

Zur Propstei

55270 Schwabenheim

Germany

Cecilia Ortíz

Institut Pasteur de Montevideo

Group Redox Biology of Trypanosomes

Mataojo 2020

11400 Montevideo

Uruguay

cortiz@pasteur.edu.uy

Gonzalo Peluffo

Departamento de Bioquímica and

Center for Free Radical and Biomedical Research

Facultad de Medicina

Universidad de la República

Avenida General Flores 2125

11800 Montevideo

Uruguay

Lucía Piacenza

Departamento de Bioquímica and

Center for Free Radical and Biomedical Research

Facultad de Medicina

Universidad de la República

Avenida General Flores 2125

11800 Montevideo

Uruguay

Sébastien Pomel1

Université Paris-Sud 11

Faculté de Pharmacie

UMR 8076 CNRS

Chimiothérapie Antiparasitaire

5 rue Jean-Baptiste Clément

92290 Châtenay-Malabry

France

sebastien.pomel@u-psud.fr

Ana Ponces Freire

Universidade de Lisboa

Faculdade de Ciências

Departamento de Química e Bioquímica

Centro de Química e Bioquímica

Edifício C8 Campo Grande

1749-016 Lisboa

Portugal

Wilfredo Quiñones

Universidad de los Andes

Laboratorio de Enzimología de Parásitos

Facultad de Ciencias

La Hechicera

Av. Alberto Carnevalli

Mérida 5101

Venezuela

Rafael Radi1

Departamento de Bioquímica and

Center for Free Radical and Biomedical Research

Facultad de Medicina

Universidad de la República

Avenida General Flores 2125

11800 Montevideo

Uruguay

rradi@fmed.edu.uy

Boris Rodenko

University of Glasgow

Institute of Infection, Immunity and Inflammation

College of Medical, Veterinary and Life Sciences

120 University Place

Glasgow G12 8TA

boris.rodenko@glasgow.ac.uk

and

The Netherlands Cancer Institute

Department of Chemical Biology

Division of Cell Biology

Plesmanlaan 121

1066 CX Amsterdam

The Netherlands

Poonam Salotra

National Institute of Pathology (ICMR)

Safdarjung Hospital Campus

Post Box 4909

New Delhi 110029

India

Puneet Saxena

University of Modena and Reggio Emilia

Department of Life Science

Via Campi 183

41125 Modena

Italy

Caroline Schönfeld

Eberhard Karls Universität Tübingen

Interfakultäres Institut für Biochemie

Hoppe-Seyler-Strasse 4

72076 Tübingen

Germany

caroline.schoenfeld@uni-tuebingen.de

Uta Schurigt

University of Würzburg

Institute for Molecular Infection Biology

Josef-Schneider-Strasse 2/D15

97080 Würzburg

Germany

Karin Seifert1

London School of Hygiene & Tropical Medicine

Faculty of Infectious and Tropical Diseases

Keppel Street

London WC1E 7HT

UK

karin.seifert@lshtm.ac.uk

Paul M. Selzer1

MSD Animal Health Innovation GmbH

Zur Propstei

55270 Schwabenheim

Germany

paul.selzer@msd.de

and

University of Tübingen

Interfaculty Institute of Biochemistry

Hoppe-Seyler-Strasse 4

72076 Tübingen

Germany

and

University of Glasgow

Institute of Infection, Immunity and Inflammation

120 University Place

Glasgow G12 8TA

UK

Joseph Shlomai1

The Hebrew University-Hadassah Medical School

Department of Microbiology and Molecular Genetics

Kuvin Center for the Study of Infectious and Tropical Diseases

Institute for Medical Research

Israel–Canada

PO Box 12272

Jerusalem 91120

Israel

josephs@ekdm.huji.ac.il

Ruchi Singh

National Institute of Pathology (ICMR)

Safdarjung Hospital Campus

Post Box 4909

New Delhi 110029

India

Marta Sousa Silva

Universidade de Lisboa

Faculdade de Ciências

Departamento de Química e Bioquímica

Centro de Química e Bioquímica

Edifício C8 Campo Grande

1749-016 Lisboa

Portugal

Jasmin Stein

Eberhard Karls Universität Tübingen

Interfakultäres Institut für Biochemie

Hoppe-Seyler-Strasse 4

72076 Tübingen

Germany

Jasmin_Stein@gmx.de

Dietmar Steverding1

University of East Anglia

BioMedical Research Centre

Norwich Medical School

Norwich Research Park

Norwich NR4 7TJ

UK

dsteverding@hotmail.com

Ana M. Tomás

Universidade do Porto

Instituto de Biologia Molecular e Celular

Rua do Campo Alegre 823

4150-180 Porto

Portugal

and

Universidade do Porto

Instituto de Ciências Biomédicas Abel Salazar

Rua de Jorge Viterbo Ferreira 228

4050-313 Porto

Portugal

and

Faculdade de Ciências

Departamento de Química e Bioquímica

Centro de Química e Bioquímica

Edifício C8 Campo Grande

1749-016 Lisboa

Portugal

Madia Trujillo

Departamento de Bioquímica and

Center for Free Radical and Biomedical Research

Facultad de Medicina

Universidad de la República

Avenida General Flores 2125

11800 Montevideo

Uruguay

Julio A. Urbina1

Instituto Venezolano de Investigaciones Científicas

Centro de Biofisica y Bioquimica

Apartado 21827

Caracas 1020A

Venezuela

and

200 Lakeside Drive No. 503

Oakland, CA 94612-3503

United States

jurbina@mac.com

Isabel M. Vincent

University of Glasgow

Wellcome Trust Centre for Molecular Parasitology

Institute of Infection, Immunity and Inflammation

College of Medical, Veterinary and Life Sciences

120 University Place

Glasgow G12 8TA

UK

and

Université Laval

Centre de Recherche en Infectiologie du CHUL

2705 Boulevard Laurier

Québec G1V 4G2

Canada

Roderick A.M. Williams1

University of Strathclyde

Strathclyde Institute for Pharmacy and Biological Sciences

161 Cathedral Street

Glasgow G4 0RE

UK

roderick.williams@strath.ac.uk

and

University of the West of Scotland School of Science

High Street

Paisley PA1 2BE

UK

roderick.williams@uws.ac.uk

Nurit Yaffe

The Hebrew University-Hadassah Medical School

Department of Microbiology and Molecular Genetics

Kuvin Center for the Study of Infectious and Tropical Diseases

Institute for Medical Research

Israel–Canada

PO Box 12272

Jerusalem 91120

Israel

Nigel Yarlett1

Pace University

The Haskins Laboratories and Chemistry and Physical Sciences

41 Park Row

New York, NY 10038

USA

nyarlett@pace.edu

Note

1. Corresponding Author

Part One

Disease Burden, Current Treatments, Medical Needs, and Strategic Approaches