Drug Induced Proteome Changes Table 2. cont. Protein ID Description RATIO Arte Peptides Arte RATIO CQ Peptides CQ PFD1035w PFD1070w PFE0340c PFE1150w PFF0510w PFF0920c PFI0975c PFL0300c PFL0720w PFL1500w PFL1550w MAL8P1.82 PF10_0031 PF14_0241 PFC0390w PFL1705w MAL7P1.81 PF08_0132 PF11_0258 PF13_0072 PFC0135c PF07_0101 PF10_0170 PF11_0396 PF11_0433 PF13_0011 PF14_0341 PF14_0706 PFB0120w PFB0640c PFB0680w PFB0830w PFC1025w PFD0800c PFD1130w PFE1350c PFF0860c PFF0880c PFL1155w PFL1340c PFL1845c steroid dehydrogenase kik-i eukaryotic initiation factor hypothetical protein, conserved multidrug resistance protein histone H3 hypothetical protein hypothetical protein phosphoesterase hypothetical protein Rab2 GTPase lipoamide dehydrogenase hypothetical protein hypothetical protein basic transcription factor 3b hypothetical protein, conserved hypothetical protein eukaryotic translation initiation factor 3 subunit glutamate dehydrogenase co-chaperone GrpE hypothetical protein conserved protein hypothetical protein hypothetical protein Protein phosphatase 2C hypothetical protein Plasmodium falciparum gamete antigen 27/25 glucose-6-phosphate isomerase hypothetical protein hypothetical protein hypothetical protein hypothetical protein Ribosomal protein S26e F49C12.11-like protein hypothetical protein hypothetical protein ubiquitin-conjugating enzyme histone H2a hypothetical protein GTP cyclohydrolase I hypothetical protein calcyclin binding protein 1.94 1.57 1.35 1.75 1.96 3.07 2.75 1.89 1.45 1.92 1.40 1.09 0.91 0.93 0.84 0.86 0.22 0.23 0.39 0.15 0.28 0.45 0.67 0.73 0.63 0.46 0.73 0.65 0.58 0.69 0.56 0.10 0.71 0.70 0.72 0.72 0.73 0.70 0.66 0.52 0.71 1 2 3 8 8 1 2 2 1 1 4 2 6 2 2 6 5 2 2 1 5 2 2 8 3 3 6 3 1 3 8 1 3 1 1 1 5 5 3 2 3 2.56 1.37 1.33 1.66 1.33 3.00 3.18 1.69 1.38 1.96 1.43 0.35 0.18 0.01 0.41 0.36 0.94 1.32 1.11 0.82 5.11 0.62 0.53 0.59 0.59 0.24 0.69 0.67 0.56 0.65 0.70 0.06 0.65 0.66 0.68 0.66 0.74 0.67 0.38 0.75 0.45 3 2 3 13 2 1 1 2 1 1 2 1 2 1 2 1 2 2 2 1 5 2 2 3 1 2 7 4 2 3 7 1 2 1 1 3 4 7 3 3 2 doi:10.1371/journal.pone.0004098.t002 proteomic changes also in other apicomplexa for which the yield of cell extracts is limited. The experimental setup (parasite stage, drug dose, incubation time) was chosen on the basis of the available literature indicating that both CQ and artemisinin do act on the late ring/early trophozoite stages of the parasites [9,10,11] on desired high protein yields and on pretesting of the drugs in our laboratory. Effects of chloroquine Chloroquine has been the mainstay of malaria prophylaxis and therapy for the last 50 years. Today, resistance to this affordable drug constitutes a major problem in the fight against malaria in most of the malaria endemic countries [12]. A range of possible mechanisms of action has been proposed for CQ. This includes interference with heme polymerization leading to the release of PLoS ONE | www.plosone.org 6 December 2008 | Volume 3 | Issue 12 | e4098