Cryptosporidium parvum is an apicomplexan zoonotic parasite recognized as the second leading-cause of diarrhoea-induced mortality in children. In contrast to other apicomplexans, C. parvum has minimalistic metabolic capacities which are almost exclusively based on glycolysis. Consequently, C. parvum is highly dependent on its host cell metabolism. In vivo (within the intestine) infected epithelial host cells are typically exposed to low oxygen pressure (1–11% O2, termed physioxia). Here, we comparatively analyzed the metabolic signatures of C. parvum-infected HCT-8 cells cultured under both, hyperoxia (21% O2), representing the standard oxygen condition used in most experimental settings, and physioxia (5% O2), to be closer to the in vivo situation. The most pronounced effect of C. parvum infection on host cell metabolism was, on one side, an increase in glucose and glutamine uptake, and on the other side, an increase in lactate release. When cultured in a glutamine-deficient medium, C. parvum infection led to a massive increase in glucose consumption and lactate production. Together, these results point to the important role of both glycolysis and glutaminolysis during C. parvum intracellular replication. Referring to obtained metabolic signatures, we targeted glycolysis as well as glutaminolysis in C. parvum-infected host cells by using the inhibitors lonidamine [inhibitor of hexokinase, mitochondrial carrier protein (MCP) and monocarboxylate transporters (MCT) 1, 2, 4], galloflavin (lactate dehydrogenase inhibitor), syrosingopine (MCT1- and MCT4 inhibitor) and compound 968 (glutaminase inhibitor) under hyperoxic and physioxic conditions. In line with metabolic signatures, all inhibitors significantly reduced parasite replication under both oxygen conditions, thereby proving both energy-related metabolic pathways, glycolysis and glutaminolysis, but also lactate export mechanisms via MCTs as pivotal for C. parvum under in vivo physioxic conditions of mammals.

The development of a waterborne pathogen detection method that is rapid, multiplex, sensitive, and specific, would be of great assistance for water treatment facilities and would help protect water consumers from harmful pathogens. Here we have utilized surface enhanced Raman spectroscopy (SERS) in a sensitive multiplex pathogen detection method. Two strategies are proposed herein, one that utilizes SERS antibody labels and one that measures the intrinsic SERS signal of organisms. For the SERS label strategy, gold nanoparticles are conjugated with antibodies specific to Cryptosporidium parvum and Giardia lamblia and with organic dye molecules. The dye molecules, rhodamine B isothiocyanate (RBITC) and malachite green isothiocyanate (MGITC) were surface enhanced by the gold nanoparticles resulting in unique fingerprint SERS spectra. The SERS label method was successful in detecting G. lamblia and C. parvum simultaneously. The method was subsequently coupled with a filtration step to both concentrate and capture cysts on a flat surface for detection. Raman mapping across the filter membrane detected ~95% of the spiked cysts in the optimized system. In the second type of strategy, intrinsic virus SERS signals were detected with silver nanoparticles for enhancement. Principal component analysis performed on the spectra data set resulted in the successful differentiation of MS2 and PhiX174 species and also for the differentiation of viable virus samples and inactivated virus samples. / Ph. D.

Foodborne disease outbreaks associated with the protozoan parasite Cryptosporidium spp. are an emerging public health concern. Shellfish, including Eastern oysters (Crassostrea virginica) in Chesapeake Bay and other Atlantic coastal waters, have been identified as a potential source of Cryptosporidium parvum infection for humans. The inactivation of C. parvum and other pathogens in raw molluscan shellfish would provide increased food safety for normal and at-risk consumers. The objectives of this study were to evaluate the efficacy of three alternative food-processing treatments (e-beam irradiation, microwave energy, and high hydrostatic pressure processing) on the viability of C. parvum oocysts in Eastern oysters. Oysters were artificially infected with the Beltsville strain of C. parvum and subjected to the three treatments in separate experiments. The effects of the treatments were evaluated by inoculation of the processed oyster tissues using the neonatal mouse bioassay. E-beam radiation of in-shell and shucked oysters treated with doses of 1.0, 1.5 or 2.0 kGy produced significant reductions (P < 0.05) in C. parvum mouse infectivity. A dose of 2.0 kGy completely terminated the infectivity of C. parvum and did not adversely affect the visual appearance of the oysters. Microwave treatments of shucked oysters at time (temperature) exposures of 1 sec (43.2°C), 2 sec (54.0°C), and 3 sec (62.5°C) produced a reduction in C. parvum mouse infectivity of 26.7%, 33.3%, and 46.7%, respectively. Microwave treatments at 2 sec (54.0°C) and 3 sec (62.5°C) showed extensive changes in oyster meat texture and color. Thus due to lack of efficacy and unacceptable tissue changes, microwave treatment of oysters is not considered a viable food processing method. High pressure processing of shucked oysters at all pressures tested (305 MPa, 370 MPa, 400 MPa, 480 MPa, 550 MPa) significantly (P < 0.05) reduced infectivity of C. parvum oocysts as measured by the neonatal mouse bioassay. A treatment of 550 MPa at 180 sec produced the maximum decrease of C. parvum infectivity (93.3%). The results indicate that HPP (high pressure processing) can produce significant (P < 0.05) reductions in infectivity of C. parvum oocysts. Measurement of tristimulus color values of pressurized raw oysters at extended processing times from 120 sec to 360 sec at 550 MPa showed an increase (P < 0.05) in whiteness. One (e-beam irradiation) of the three food-processing treatments shows promise for commercial applications to reduce public health risks from cryptosporidiosis in Eastern oysters. / Ph. D.

La multichimiorésistance est caractérisée par une résistance simultanée à des agents chimiothérapeutiques de structures diverses, induite notamment par l’efflux des substances actives hors des cellules. Les transporteurs ABC (ATP-Binding Cassette) sont des protéines transmembranaires impliquées dans cet efflux et qui participent à l’échec du traitement de certains cancers. Par ailleurs, ce mécanisme d’efflux a également été évoqué dans le cadre de la résistance de certains microorganismes aux antimicrobiens. Dans cette étude, nous avons conçu et synthétisé des dérivés susceptibles d’inhiber certains transporteurs ABC, en particulier, la glycoprotéine-P (Pgp) impliquée dans la multichimiorésistance des tumeurs humaines, et CpABC3, rencontré chez le parasite Cryptosporidium parvum. Dans un premier temps, nous avons synthétisé trois dérivés de type 4-alkyl-imidazo[4,5-b]pyridin-7-one, hétérocycles destinés à se fixer sur le site à ATP des transporteurs ABC. L’activité de ces composés a été évaluée vis-à-vis d’un fragment recombinant (H6-NBD1) de CpABC3, et un de ceux-ci a montré une liaison (faible) à ce fragment. Nous avons ensuite préparé dix-sept dérivés bivalents susceptibles d’inhiber la Pgp, constitués d’une molécule d’adénine (ciblant le site à ATP) reliée à la progestérone (ciblant le site aux stéroïdes) par un bras de géométrie variable. Ces dérivés ont été testés sur des lignées cellulaires K562/R7 surexprimant la Pgp, et un de ceux-ci a montré une activité supérieure à celle de la progestérone. Enfin, nous avons mis au point une synthèse de chaînes de type oligocyclohexylidène, qui sont de bons candidats pour constituer des bras espaceurs rigides / Multi-drug resistance (MDR) is characterized by a simultaneous resistance to a wide range of structurally unrelated chemotherapeutic agents, partly caused by the efflux of active compounds out of the cell. ABC transporters (ATP-Binding Cassette) are transmembrane proteins implicated in this efflux, and thus, they contribute to the failure of some cancer treatments. Furthermore, this mechanism was evoked in some microorganism resistances to antimicrobial agents. In this study, we designed and synthesized potential inhibitors of ABC transporters, especially P-glycoprotein (Pgp) implicated in human tumors multi-drug resistance, and CpABC3, a transporter found in a human parasite, Cryptosporidium parvum. First, we synthesized three 4-alkyl-imidazo[4,5-b]pyridin-7-one derivatives, targeting ATP-binding site of ABC transporters. Their biological activities were evaluated toward a recombinant fragment of the CpABC3 transporter (H6-NBD1 fragment). One of these compounds showed a weak-binding to this fragment. Next, we prepared seventeen progesterone-adenine hybrids as potential bivalent ligands which may bind simultaneously to the ATP-binding site and the steroid-binding region. We chose to synthesize derivatives with rather short-length linkers with different conformational flexibilities. These bivalent compounds were tested on K562/R7 human leukemic cells overexpressing Pgp. One of them has showed a better activity than progesterone. Finally, we optimized the synthesis of oligocyclohexylidene chains, which are good candidates to constitute rigid linkers

Esta pesquisa avaliou o uso de ozônio para inativar cistos de Giardia spp. e oocistos de Cryptosporidium parvum presentes na água filtrada obtida após a utilização da tecnologia de ciclo completo com flotação &#40;coagulação, floculação, flotação e filtração&#41; em escala de bancada, empregando o cloreto de polialumínio &#8211; PAC &#8211; como coagulante. O método de floculação em carbonato de cálcio &#8211; FCCa, sem e com a etapa de separação imunomagnética &#8211; IMS &#8211; foi utilizado na quantificação dos protozoários. A recuperação nos ensaios de qualidade utilizando o kit Easyseed&#174; de Giardia spp. foi de 8,4&#37; &#177; 97,4&#37; sem IMS e com IMS, com duas dissociações, o valor foi de 7,4&#37; &#177; 39,7&#37; e, com três dissociações, a recuperação alcançou 9,6&#37; &#177; 34,7&#37;, portanto, somente o ensaio com IMS e duas dissociações, não atendeu os padrões do Método 1623.1. A recuperação de Cryptosporidium parvum, obteve valor de 3,4&#37; &#177; 100&#37; em ensaio sem IMS e com IMS, o valor obtido foi de 1,0&#37; &#177; 70,0&#37; com duas dissociações e 1,8&#37; &#177; 44,4&#37; com três dissociações e nos três métodos apresentados, não houve conformidade com os critérios do Método 1623.1. Na etapa de desinfecção com ozônio, os ensaios realizados na Etapa 1, que se utilizou 5 mgO3L-1 e tempo de contato de 1 min sem IMS, as maiores inativações atingidas foram de 2,52 e 2,22 log para cistos de Giardia spp. e oocistos de Cryptosporidium parvum, respectivamente. Com o tempo de contato de 5 min, as maiores inativações foram de 2,52 e 2,92 log de cistos de Giardia spp. e oocistos de Cryptosporidium parvum, respectivamente. Na Etapa 2, com IMS, utilizando a mesma dosagem e tempo de contato de 1 min, obteve-se 2,27 e 0,21 log de inativação para cistos e oocistos, respectivamente. Comparando-se com o tempo de contato de 5 min, foram obtidos 2,9 e 2,3 log de inativação para cistos e oocistos, respectivamente. Na avaliação de custo, o método de FCCa sem IMS demonstrou ser o mais econômico em relação ao procedimento com IMS. A influência da inclusão da terceira dissociação ácida no método com IMS também foi analisada e este procedimento não resultou em diferenças estatísticas significativas nos resultados. / This research evaluated the use of ozone to inactivate Giardia spp. cysts and Cryptosporidium parvum oocysts present in the filtered water obtained after the use of the complete cycle of flotation technology &#40;coagulation, flocculation, flotation and filtration&#41; on a bench scale employing polyaluminium chloride - PAC as coagulant. The calcium carbonate flocculation method - FCCa, without and with immunomagnetic separation step - IMS has been used in the quantification of protozoa. The recovery in quality test using the kit Easyseed&#174; for Giardia spp. was 8.4&#37; &#177; 97.4&#37; non-IMS and IMS with two dissociations, the value was 7.4&#37; &#177;39.7&#37; and with three dissociations, the recovery reached 9.6&#37; &#177; 34,7&#37;, so only the test with IMS and two dissociations, did not meet the standards of method 1623.1. Recovery of Cryptosporidium parvum obtained value of 3.4&#37; &#177; 100&#37; in non-IMS and IMS testing, the value obtained was 1.0&#37; &#177; 70.0&#37; with two dissociations and 1.8&#37; &#177; 44.4&#37; with three dissociations and the three methods presented, there was non-compliance with the criteria of Method 1623.1. In step disinfection with ozone, tests performed in Step 1 was used 5 mgO3L-1 and contact time of 1 min without IMS, the major inactivation achieved were 2.52 and 2.22 log for Giardia spp. cysts and Cryptosporidium parvum oocysts, respectively. With 5 minutes of contact time, the greater inactivation were 2.52 and 2.92 log for Giardia spp. cysts and Cryptosporidium parvum oocysts, respectively. In Step 2, with IMS, using the same dose and 1 min contact time, there was obtained 2.27 and 0.21 log inactivation for cysts and oocysts, respectively. Compared with the 5 min of contact time, were obtained 2.9 and 2.3 log inactivation for cysts and oocysts, respectively. In evaluating cost, the FCCa method without IMS proved to be the most economical in relation to the procedure with IMS. The influence of inclusion of the third acid dissociation method in IMS was also analyzed and this procedure did not result in statistically significant differences in the results.

Este trabalho teve como objetivo avaliar diversos métodos de detecção e recuperação de cistos de Giardia spp. e de oocistos de Cryptosporidium parvum em resíduos gerados no tratamento de águas de abastecimento com turbidez elevada tendo como padrão o Método 1623.1 da USEPA &#40;2012 &#41;. Para tanto, ensaios utilizando aparelho Jarteste &#40;coagulação, floculação, decantação e filtração &#41; foram realizados utilizando o coagulante cloreto de polialumínio &#45; PAC. Em todos os métodos avaliados foi utilizada a técnica de purificação por separação imunomagnética &#45; IMS. A adaptação do método floculação em carbonato de cálcio FCCa elaborado por Vesey et al. &#40;1993&#41; e adaptado por Feng et al. &#40;2011&#41;, repercutiu nos melhores resultados para a amostra de resíduo sedimentado, com recuperações de 68 &#177; 17 &#37; para oocisto de C. parvum e de 42 &#177; 7 &#37; para cisto de Giardia spp. Entretanto, as recuperações para a amostra de água de lavagem dos filtros &#45; ALF foram inferiores à 1 &#37;, não sendo possível determinar um método adequado. A presença dos patógenos indica que o reuso da ALF em ETA convencionais ou o descarte em mananciais sem um tratamento prévio, pode representar problemas de contaminação. A adaptação dos métodos de Boni de Oliveira &#40;2012&#41; e Keegan et al. &#40;2008&#41;, também repercutiram em porcentagens de recuperação expressivas para a amostra de resíduo sedimentado, sendo de: 41 &#177; 35 &#37; para oocisto de C. parvum e 11 &#177; 70 &#37; para cisto de Giardia spp., e 38 &#177; 26 &#37; para oocisto de C. parvum e 26 &#177; 13 &#37; para cisto de Giardia spp., respectivamente. A análise estatística não resultou em diferença significativa entre estes dois métodos, entretanto, as elevadas recuperações indicam que estes métodos podem ser melhor avaliados em pesquisas futuras. / This dissertation addresses the evaluation of several methods for the detection of Giardia spp. cysts and Cryptosporidium parvum oocysts in wastes produced after a high-turbidity water treatment, according to Method 1623.1 from USEPA &#40;2012&#41;. Coagulant polyaluminium chloride &#45; PACl was used in jar test experiments &#40;coagulation/flocculation, sedimentation and filtration &#41;. The Immunomagnetic Separation &#45; IMS technique was applied to all methods. The calcium carbonate flocculation &#40;CCF&#41; method, developed by Vesey et al. &#40;1993&#41; and adapted by Feng et al. &#40;2011 &#41;, was applied to sludge samples in this research and was the best method tested, with 68% &#177; 17 &#37; and 42 &#37; &#177; 7,00 &#37; recoveries for C. parvum oocysts and Giardia spp. cysts, respectively. On the other hand, the percentage recovery of (oo)cysts for filter backwash water samples was lower than 1 &#37; and no suitable method could be detected. The presence of pathogens represents contamination risks for water sources and the reuse of filter backwash water may be a problem to conventional water treatment plants. The application of Boni de Oliveira &#40;2012&#41; and Keegan et al. &#40;2008&#41; methods, adjusted to this study, also resulted in significant percentage recoveries for the sludge samples, with 41 &#177; 35 &#37; for C. parvum oocyst and 11 &#177; 70&#37; for cyst Giardia spp., and 38 &#177; 26&#37; for oocyst C. parvum and 26 &#177; 13&#37; for cyst Giardia spp., respectively. The statistical analysis showed no significant differences between the two methods, however, such high recoveries indicate they should be better evaluated in future research.

Reproduction de : Thèse de doctorat : Parasitologie : Lille 2 : 2008. / Résumé en français et en anglais. Titre provenant de l'écran-titre. Bibliogr. f. 178-195.

Este trabalho teve como objetivo avaliar diversos métodos de detecção e recuperação de cistos de Giardia spp. e de oocistos de Cryptosporidium parvum em resíduos gerados no tratamento de águas de abastecimento com turbidez elevada tendo como padrão o Método 1623.1 da USEPA &#40;2012 &#41;. Para tanto, ensaios utilizando aparelho Jarteste &#40;coagulação, floculação, decantação e filtração &#41; foram realizados utilizando o coagulante cloreto de polialumínio &#45; PAC. Em todos os métodos avaliados foi utilizada a técnica de purificação por separação imunomagnética &#45; IMS. A adaptação do método floculação em carbonato de cálcio FCCa elaborado por Vesey et al. &#40;1993&#41; e adaptado por Feng et al. &#40;2011&#41;, repercutiu nos melhores resultados para a amostra de resíduo sedimentado, com recuperações de 68 &#177; 17 &#37; para oocisto de C. parvum e de 42 &#177; 7 &#37; para cisto de Giardia spp. Entretanto, as recuperações para a amostra de água de lavagem dos filtros &#45; ALF foram inferiores à 1 &#37;, não sendo possível determinar um método adequado. A presença dos patógenos indica que o reuso da ALF em ETA convencionais ou o descarte em mananciais sem um tratamento prévio, pode representar problemas de contaminação. A adaptação dos métodos de Boni de Oliveira &#40;2012&#41; e Keegan et al. &#40;2008&#41;, também repercutiram em porcentagens de recuperação expressivas para a amostra de resíduo sedimentado, sendo de: 41 &#177; 35 &#37; para oocisto de C. parvum e 11 &#177; 70 &#37; para cisto de Giardia spp., e 38 &#177; 26 &#37; para oocisto de C. parvum e 26 &#177; 13 &#37; para cisto de Giardia spp., respectivamente. A análise estatística não resultou em diferença significativa entre estes dois métodos, entretanto, as elevadas recuperações indicam que estes métodos podem ser melhor avaliados em pesquisas futuras. / This dissertation addresses the evaluation of several methods for the detection of Giardia spp. cysts and Cryptosporidium parvum oocysts in wastes produced after a high-turbidity water treatment, according to Method 1623.1 from USEPA &#40;2012&#41;. Coagulant polyaluminium chloride &#45; PACl was used in jar test experiments &#40;coagulation/flocculation, sedimentation and filtration &#41;. The Immunomagnetic Separation &#45; IMS technique was applied to all methods. The calcium carbonate flocculation &#40;CCF&#41; method, developed by Vesey et al. &#40;1993&#41; and adapted by Feng et al. &#40;2011 &#41;, was applied to sludge samples in this research and was the best method tested, with 68% &#177; 17 &#37; and 42 &#37; &#177; 7,00 &#37; recoveries for C. parvum oocysts and Giardia spp. cysts, respectively. On the other hand, the percentage recovery of (oo)cysts for filter backwash water samples was lower than 1 &#37; and no suitable method could be detected. The presence of pathogens represents contamination risks for water sources and the reuse of filter backwash water may be a problem to conventional water treatment plants. The application of Boni de Oliveira &#40;2012&#41; and Keegan et al. &#40;2008&#41; methods, adjusted to this study, also resulted in significant percentage recoveries for the sludge samples, with 41 &#177; 35 &#37; for C. parvum oocyst and 11 &#177; 70&#37; for cyst Giardia spp., and 38 &#177; 26&#37; for oocyst C. parvum and 26 &#177; 13&#37; for cyst Giardia spp., respectively. The statistical analysis showed no significant differences between the two methods, however, such high recoveries indicate they should be better evaluated in future research.

Esta pesquisa avaliou o uso de ozônio para inativar cistos de Giardia spp. e oocistos de Cryptosporidium parvum presentes na água filtrada obtida após a utilização da tecnologia de ciclo completo com flotação &#40;coagulação, floculação, flotação e filtração&#41; em escala de bancada, empregando o cloreto de polialumínio &#8211; PAC &#8211; como coagulante. O método de floculação em carbonato de cálcio &#8211; FCCa, sem e com a etapa de separação imunomagnética &#8211; IMS &#8211; foi utilizado na quantificação dos protozoários. A recuperação nos ensaios de qualidade utilizando o kit Easyseed&#174; de Giardia spp. foi de 8,4&#37; &#177; 97,4&#37; sem IMS e com IMS, com duas dissociações, o valor foi de 7,4&#37; &#177; 39,7&#37; e, com três dissociações, a recuperação alcançou 9,6&#37; &#177; 34,7&#37;, portanto, somente o ensaio com IMS e duas dissociações, não atendeu os padrões do Método 1623.1. A recuperação de Cryptosporidium parvum, obteve valor de 3,4&#37; &#177; 100&#37; em ensaio sem IMS e com IMS, o valor obtido foi de 1,0&#37; &#177; 70,0&#37; com duas dissociações e 1,8&#37; &#177; 44,4&#37; com três dissociações e nos três métodos apresentados, não houve conformidade com os critérios do Método 1623.1. Na etapa de desinfecção com ozônio, os ensaios realizados na Etapa 1, que se utilizou 5 mgO3L-1 e tempo de contato de 1 min sem IMS, as maiores inativações atingidas foram de 2,52 e 2,22 log para cistos de Giardia spp. e oocistos de Cryptosporidium parvum, respectivamente. Com o tempo de contato de 5 min, as maiores inativações foram de 2,52 e 2,92 log de cistos de Giardia spp. e oocistos de Cryptosporidium parvum, respectivamente. Na Etapa 2, com IMS, utilizando a mesma dosagem e tempo de contato de 1 min, obteve-se 2,27 e 0,21 log de inativação para cistos e oocistos, respectivamente. Comparando-se com o tempo de contato de 5 min, foram obtidos 2,9 e 2,3 log de inativação para cistos e oocistos, respectivamente. Na avaliação de custo, o método de FCCa sem IMS demonstrou ser o mais econômico em relação ao procedimento com IMS. A influência da inclusão da terceira dissociação ácida no método com IMS também foi analisada e este procedimento não resultou em diferenças estatísticas significativas nos resultados. / This research evaluated the use of ozone to inactivate Giardia spp. cysts and Cryptosporidium parvum oocysts present in the filtered water obtained after the use of the complete cycle of flotation technology &#40;coagulation, flocculation, flotation and filtration&#41; on a bench scale employing polyaluminium chloride - PAC as coagulant. The calcium carbonate flocculation method - FCCa, without and with immunomagnetic separation step - IMS has been used in the quantification of protozoa. The recovery in quality test using the kit Easyseed&#174; for Giardia spp. was 8.4&#37; &#177; 97.4&#37; non-IMS and IMS with two dissociations, the value was 7.4&#37; &#177;39.7&#37; and with three dissociations, the recovery reached 9.6&#37; &#177; 34,7&#37;, so only the test with IMS and two dissociations, did not meet the standards of method 1623.1. Recovery of Cryptosporidium parvum obtained value of 3.4&#37; &#177; 100&#37; in non-IMS and IMS testing, the value obtained was 1.0&#37; &#177; 70.0&#37; with two dissociations and 1.8&#37; &#177; 44.4&#37; with three dissociations and the three methods presented, there was non-compliance with the criteria of Method 1623.1. In step disinfection with ozone, tests performed in Step 1 was used 5 mgO3L-1 and contact time of 1 min without IMS, the major inactivation achieved were 2.52 and 2.22 log for Giardia spp. cysts and Cryptosporidium parvum oocysts, respectively. With 5 minutes of contact time, the greater inactivation were 2.52 and 2.92 log for Giardia spp. cysts and Cryptosporidium parvum oocysts, respectively. In Step 2, with IMS, using the same dose and 1 min contact time, there was obtained 2.27 and 0.21 log inactivation for cysts and oocysts, respectively. Compared with the 5 min of contact time, were obtained 2.9 and 2.3 log inactivation for cysts and oocysts, respectively. In evaluating cost, the FCCa method without IMS proved to be the most economical in relation to the procedure with IMS. The influence of inclusion of the third acid dissociation method in IMS was also analyzed and this procedure did not result in statistically significant differences in the results.

Die Kryptosporidiose stellt aufgrund ihres zoonotischen Charakters und der Entwicklung chronischer Durchfälle bei Immunsupprimierten ein hohes Gesundheitsrisiko für den Menschen, aber ebenso für Tiere dar. Derzeit verfügbare Therapeutika ermöglichen keine zuverlässige Bekämpfung klinischer Symptome oder eine Erregerelimination, daher ist die Erforschung neuer Therapieansätze dringend notwendig. CDPK stellen in diesem Zusammenhang interessante Zielmoleküle dar, da sie zwar in Pflanzen und Protisten einschließlich Apikomplexa, jedoch nicht in Pilzen und Säugetieren vorkommen. Trotz der Entdeckung vielversprechender neuer Wirkstoffe gegen CpCDPK1 in den letzten Jahren ist zur Lokalisation und Funktion von CDPK in C. parvum wenig bekannt.Diese Arbeit belegt die Transkription von sechs CpCDPK in vitro und beschreibt erstmals die Länge der 3’UTR von CpCDPK. Die Translation wurde durch den Nachweis spezifischen Proteins in Sporozoiten im Immunoblot sowie die Lokalisation von CpCDPK1 mit Hilfe der Immunfluoreszenz belegt. Möglicherweise wird die CpCDPK1 durch N-Myristoylierung an Membranen gebunden, an die Oberfläche von Zoiten gebracht und sezerniert. Eine Rolle des Enzyms im Invasions- und Egressmechanismus des Parasiten wird diskutiert.