Macromolecular inhibitors of malarial cysteine proteases —An invited review

Kailash C. Pandey

Host-Parasite Interaction Biology Group, Protein-Protein Interaction Unit, National Institute of Malaria Research, (ICMR) Sector-8, Dwarka, India.

DOI: 10.4236/jbise.2013.69108                

Abstract

There are evidences indicating that cysteine proteases play an essential role in malaria parasites; therefore, an obvious area of investigation is the inhibition of these enzymes to treat malaria. Small cysteine protease inhibitors of malaria are well studied, but macromolecular nature of inhibitor is a new field to explore. In malarial cysteine proteases, there are macromolecular endogenous inhibitors playing important roles in regulation of the cysteine protease activity of parasite and host. Recent studies suggested that there are known and characterized endogenous inhibitors like falstatin present in P. falciparum, PbICP (inhibitor of cysteine protease in P. berghei), PyICP (inhibitor of cysteine protease in P. yoelli), and other macromolecular inhibitors which are the prodomain of enzyme itself regulating the activity of the mature enzyme. All the known macromolecular endogenous inhibitors are using specific loop-like structure to interact with malarial cysteine proteases. The majority of macromolecular inhibitors are competitive in nature, and block access to the active site of their target protease, but do not bind in a strictly substrate-like manner. They rather interact with the protease subsites and catalytic residues in a non-catalytically competent manner. In future, designing inhibitors based on these protein-protein interactions will be a new approach in the field of malaria. Since macromolecular inhibitors can gain potency through the burial of a large surface area and specificity through contacts with secondary binding sites critical for inhibition, and could be less prone to drug resistant mutation.

Keywords

Malaria; Cysteine Protease; Hemoglobinase; Macromolecular Inhibitor; Protein-Protein Interaction

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	[1] Farady, C.J. and Craik, C.S. (2013) Mechanisms of macromolecular protease inhibitors. ChemBioChem, 11, 2341-2346.
[2]	Phan, J., Zdanov, A., Evdokimov, A.G., Tropea, J.E., Peters, H.P., et al. (2002) Structural basis for the substrate specificity of tobacco etch virus protease. The Journal of Biological Chemistry, 277, 50564-50572. doi:10.1074/jbc.M207224200
[3]	Pandey, K.C. and Dixit, R. (2012) Structure-function of falcipains: malarial cysteine proteases. Journal of Tropical Medicine, 2012, 345195. doi:10.1155/2012/345195
[4]	Na, B.K., Shenai, B.R., Sijwali, P.S., Choe, Y., Pandey, K.C., et al. (2004) Identification and biochemical characterization of vivapains, cysteine proteases of the malaria parasite Plasmodium vivax. Biochemical Journal, 378, 529-538. doi:10.1042/BJ20031487
[5]	Na, B.K., Bae, Y.-A., Zo, Y.-G., Choe, Y., Kim, S.-H., et al. (2010) Biochemical properties of a novel cysteine protease of Plasmodium vivax, vivapain-4. PLOS Neglected Tropical Diseases, 4, e849. doi:10.1371/journal.pntd.0000849
[6]	Singh, A, Shenai, B.R., Choe, Y., et al. (2002) Critical role of amino acid 23 in mediating activity and specificity of vinckepain-2, a papain-family cysteine protease of rodent malaria parasites, Biochemical Journal, 368, 273-281. doi:10.1042/BJ20020753
[7]	Prasad, R., Soni, A.A., Puri, S.K., et al. (2013) Expression, characterization, and cellular localization of knowpains, papain-like cysteine proteases of the Plasmodium knowlesi malaria parasite. PLoS ONE, 7, e51619.
[8]	Aly, A.S. and Matuschewski, K. (2005) A malarial cysteine protease is necessary for Plasmodium sporozoite egress from oocysts. The Journal of Experimental Medicine, 202, 225-230.
[9]	Rennenberg, A., Lehmann, C., Heitmann, A., et al. (2010) Exoerythrocytic Plasmodium parasites secrete a cysteine protease inhibitor involved in sporozoite invasion and capable of blocking cell death of host hepatocytes. PLoS Pathogens, 6, e1000825. doi:10.1371/journal.ppat.1000825
[10]	Pandey, K.C., Singh, N., Arastu-Kapur, S., Bogyo, M., and Rosenthal, P.J. (2006) Falstatin, a cysteine protease inhibitor of Plasmodium falciparum, facilitates erythrocyte invasion. PLoS Pathogens, 2, e117. doi:10.1371/journal.ppat.0020117
[11]	Pandey, K.C. (2011) Centenary celebrations article: Cysteine proteases of human malaria parasites. Journal of parasitic Diseases, 35, 94-103.
[12]	Monteiro, A.C., Abrahamson, M., Lima, et al. (2001) Identification, characterization and localization of chagasin, a tight-binding cysteine protease inhibitor in Trypanosoma cruzi. Journal of Cell Science, 114, 3933-3942.
[13]	Wang, S.X., Pandey, K.C., Scharfstein, J., et al. (2007) The structure of chagasin in complex with a cysteine protease clarifies the binding mode and evolution of an inhibitor family. Structure, 15, 535-543. doi:10.1016/j.str.2007.03.012
[14]	Wang, S.X., Pandey, K.C., Somoza, J.R., et al. (2006) Structural basis for unique mechanisms of folding and hemoglobin binding by a malarial protease. PNAS, 103, 11503-11508. doi:10.1073/pnas.0600489103
[15]	Sijwali, P.S., Shenai, B.R., Gut, J., Singh, A. and Rosenthal, P.J. (2001) Expression and characterization of the Plasmodium falciparum haemoglobinase falcipain-3. Biochemical Journal, 360, 481-489. doi:10.1042/0264-6021:3600481
[16]	Shenai, B.R., Sijwali, P.S., Singh, A., Rosenthal, P.J. (2000) Characterization of native and recombinant falcipain-2, a principal trophozoite cysteine protease and essential hemoglobinase of Plasmodium falciparum. The Journal of Biological Chemistry, 37, 29000-29010.
[17]	Rosenthal, P.J. (2004) Cysteine Proteases of malaria parasites. International Journal for Parasitology, 34, 1489-1499. doi:10.1016/j.ijpara.2004.10.003
[18]	Sijwali, P.S., Shenai, B.R. and Rosenthal, P.J. (2002) Folding of the Plasmodium falciparum cysteine protease falcipain-2 is mediated by a chaperone-like peptide and not the prodomain. The Journal of Biological Chemistry, 277, 14910-14915. doi:10.1074/jbc.M109680200
[19]	Pandey, K.C., Barkan, D.T., Sali, A. and Rosenthal, P.J. (2009) Regulatory elements within the prodomain of Falcipain-2, a cysteine protease of the malaria parasite Plasmodium falciparum. PloS one, 4, e5694. doi:10.1371/journal.pone.0005694
[20]	Sundararaj, S., Singh, D., Saxena, A.K., Vashisht, K., Sijwali, P.S., Dixit, R. and Pandey, K.C. (2012) The Ionic and hydrophobic interactions are required for the auto activation of cysteine proteases of Plasmodium falciparum. PloS one, 7, e47227. doi:10.1371/journal.pone.0047227
[21]	Wiederanders, B., Kaulmann, G. and Schilling, K. (2003) Functions of propeptide parts in cysteine proteases. Current Protein & Peptide Science, 4, 309-326. doi:10.2174/1389203033487081
[22]	Groves, M.R., Coulombe, R., Jenkins, J. and Cygler, M. (1998) Structural basis for specificity of papain-like cysteine protease proregions toward their cognate enzymes. Proteins, 32, 504-514. doi:10.1002/(SICI)1097-0134(19980901)32:4<504::AID-PROT8>3.0.CO;2-F
[23]	Pandey, K.C., Singh, N., Kapur, A.S., Bogyo, M., Rosenthal, P.J. (2006) Falstatin, a cysteine protease inhibitor of Plasmodium falciparum, facilitates erythrocyte invasion. PLoS Pathog, 2, e117. doi:10.1371/journal.ppat.0020117
[24]	Hansen, G., Heitmann, A., Witt, T., et al. (2011) Structural basis for the regulation of cysteine-protease activity by a new class of protease inhibitors in Plasmodium. Structure, 19, 919-929.doi:10.1016/j.str.2011.03.025
[25]	Pandey, K.C., Wang, S.X., Sijwali, P.S., Lau, A.L., McKerrow, J.H. and Rosenthal, P.J. (2005) The Plasmodium falciparum cysteine protease falcipain-2 captures its substrate, hemoglobin, via a unique motif. Proceedings of the National Academy of Sciences of the United States of America, 102, 9138-9143. doi:10.1073/pnas.0502368102
[26]	Storer, A.C. and Menard, R. (1994) Catalytic mechanism in papain family of cysteine peptidases. Methods in Enzymology, 244, 486-500. doi:10.1016/0076-6879(94)44035-2
[27]	Pei, Y., Miller, J.L., Lindner, S.E., et al. (2013) Plasmodium yoelii inhibitor of cysteine proteases is exported to exomembrane structures and interacts with yoelipain-2 during asexual blood-stage development. Cellular Microbiology, 15, 1508-1526. doi:10.1111/cmi.12124
[28]	Riekenberg, S., Witjes, B., Saric, M., Bruchhaus, I. and Scholze, H. (2005) Identification of EhICP1, a chagasinlike cysteine protease inhibitor of Entamoeba histolytica. FEBS Letters, 579, 1573-1578.
[29]	Cardinalea, D., Guaitolia, G., Tondia, D., et al. (2011) Inhibition of calpain by mimicking a natural proteinprotein interaction between Protein-protein interfacebinding peptides inhibit the cancer therapy target human thymidylate synthase. PNAS, 108, E542-E549.
[30]	Shahian, T., Lee, G.M., Lazic, A., et al. (2009) Inhibition of a viral enzyme by a small-molecule dimer disruptor. Nature Chemical Biology, 5, 640-646.
[31]	Leader, B., Baca, Q.J. and Golan, D.E. (2008) Protein therapeutics: A summary and pharmacological classification. Nature Reviews Drug Discovery, 7, 21-39.