1
|
Huang L, Jasim I, Alkorjia O, Agca C, Oksman A, Agca Y, Goldberg DE, Benson JD, Almasri M. An impedance based microfluidic sensor for evaluation of individual red blood cell solute permeability. Anal Chim Acta 2023; 1267:341226. [PMID: 37257960 DOI: 10.1016/j.aca.2023.341226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 04/10/2023] [Accepted: 04/17/2023] [Indexed: 06/02/2023]
Abstract
-In this paper, we investigate a microfluidic based sensing device for cell membrane permeability measurements in real time with applications in rapid assessment of red blood cell (RBC) quality at the individual cell level. The microfluidic chip was designed with unique abilities to line up the RBCs in the centerline of the microchannel using positive dielectrophoresis (p-DEP) forces, rapid mixing of RBCs with various media (e.g. containing permeating or nonpermeating solutes) injected from different inlets to achieve high mixing efficiency. The chip detects the impedance values of the RBCs within 0.19 s from the start of mixing with other media, at ten electrodes along the length of the channel and enables time series measurements of volume change of individual cell caused by cell osmosis in anisosmotic fluids over a 0.8 s postmixing timespan. This technique enables estimating water permeability of individual cell accurately. Here we first present confirmation of a linear voltage-diameter relationship in polystyrene bead standards. Next, we show that under equilibrium conditions, the voltage-volume relationship in rat red blood cells (RBCs) is linear, corresponding to previously published Boyle van 't Hoff plots. Using rat cells as a model for human, we present the first measurement of water permeability in individual red blood cells and confirm that these data align with previously published population level values for human RBC. Finally, we present preliminary evidence for possible application of our device to identify individual RBCs infected with Plasmodium falciparum malaria parasites. Future developments using this device will address the use of whole blood with non-homogenous cell populations, a task currently performed by clinical Coulter counters.
Collapse
Affiliation(s)
- Lining Huang
- Department of Electrical Engineering and Computer Science, University of Missouri-Columbia, MO, USA
| | - Ibrahim Jasim
- Department of Electrical Engineering and Computer Science, University of Missouri-Columbia, MO, USA
| | - Omar Alkorjia
- Department of Electrical Engineering and Computer Science, University of Missouri-Columbia, MO, USA
| | - Cansu Agca
- Department of Veterinary Pathology, University of Missouri-Columbia, MO, USA
| | - Anna Oksman
- Department of Medicine, Division of Infectious Diseases, and Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO, 63130, USA
| | - Yuksel Agca
- Department of Veterinary Pathology, University of Missouri-Columbia, MO, USA
| | - Daniel E Goldberg
- Department of Medicine, Division of Infectious Diseases, and Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO, 63130, USA
| | - James D Benson
- Department of Biology, University of Saskatchewan, Saskatoon, SK, Canada.
| | - Mahmoud Almasri
- Department of Electrical Engineering and Computer Science, University of Missouri-Columbia, MO, USA.
| |
Collapse
|
2
|
Paing MM, Salinas ND, Adams Y, Oksman A, Jensen AT, Goldberg DE, Tolia NH. Shed EBA-175 mediates red blood cell clustering that enhances malaria parasite growth and enables immune evasion. eLife 2018; 7:43224. [PMID: 30556808 PMCID: PMC6305201 DOI: 10.7554/elife.43224] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 12/14/2018] [Indexed: 01/22/2023] Open
Abstract
Erythrocyte Binding Antigen of 175 kDa (EBA-175) has a well-defined role in binding to glycophorin A (GpA) during Plasmodium falciparum invasion of erythrocytes. However, EBA-175 is shed post invasion and a role for this shed protein has not been defined. We show that EBA-175 shed from parasites promotes clustering of RBCs, and EBA-175-dependent clusters occur in parasite culture. Region II of EBA-175 is sufficient for clustering RBCs in a GpA-dependent manner. These clusters are capable of forming under physiological flow conditions and across a range of concentrations. EBA-175-dependent RBC clustering provides daughter merozoites ready access to uninfected RBCs enhancing parasite growth. Clustering provides a general method to protect the invasion machinery from immune recognition and disruption as exemplified by protection from neutralizing antibodies that target AMA-1 and RH5. These findings provide a mechanistic framework for the role of shed proteins in RBC clustering, immune evasion, and malaria.
Collapse
Affiliation(s)
- May M Paing
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, United States
| | - Nichole D Salinas
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, United States.,Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, United States
| | - Yvonne Adams
- Centre for Medical Parasitology at Department of Immunology and Microbiology (ISIM), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anna Oksman
- Department of Medicine, Washington University School of Medicine, St. Louis, United States
| | - Anja Tr Jensen
- Centre for Medical Parasitology at Department of Immunology and Microbiology (ISIM), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Daniel E Goldberg
- Department of Medicine, Washington University School of Medicine, St. Louis, United States
| | - Niraj H Tolia
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, United States.,Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, United States
| |
Collapse
|
3
|
Nasamu AS, Glushakova S, Russo I, Vaupel B, Oksman A, Kim AS, Fremont DH, Tolia N, Beck JR, Meyers MJ, Niles JC, Zimmerberg J, Goldberg DE. Plasmepsins IX and X are essential and druggable mediators of malaria parasite egress and invasion. Science 2018; 358:518-522. [PMID: 29074774 PMCID: PMC5928414 DOI: 10.1126/science.aan1478] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 09/18/2017] [Indexed: 01/31/2023]
Abstract
Proteases of the malaria parasite Plasmodium falciparum have long been investigated as drug targets. The P. falciparum genome encodes 10 aspartic proteases called plasmepsins, which are involved in diverse cellular processes. Most have been studied extensively but the functions of plasmepsins IX and X (PMIX and PMX) were unknown. Here we show that PMIX is essential for erythrocyte invasion, acting on rhoptry secretory organelle biogenesis. In contrast, PMX is essential for both egress and invasion, controlling maturation of the subtilisin-like serine protease SUB1 in exoneme secretory vesicles. We have identified compounds with potent antimalarial activity targeting PMX, including a compound known to have oral efficacy in a mouse model of malaria.
Collapse
Affiliation(s)
- Armiyaw S Nasamu
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA.,Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Svetlana Glushakova
- Section on Integrative Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ilaria Russo
- Faculty of Biology, Medicine and Health, Division of Infection Immunity and Respiratory Medicine, School of Biological Sciences, University of Manchester, Manchester, UK
| | - Barbara Vaupel
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA.,Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Anna Oksman
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA.,Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Arthur S Kim
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA.,Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Daved H Fremont
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Niraj Tolia
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Josh R Beck
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA.,Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| | - Marvin J Meyers
- Center for World Health and Medicine, Saint Louis University School of Medicine, Saint Louis, MO 63104, USA
| | - Jacquin C Niles
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Joshua Zimmerberg
- Section on Integrative Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Daniel E Goldberg
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, Saint Louis, MO 63110, USA. .,Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO 63110, USA
| |
Collapse
|
4
|
Mallari JP, Oksman A, Vaupel B, Goldberg DE. Kinase-associated endopeptidase 1 (Kae1) participates in an atypical ribosome-associated complex in the apicoplast of Plasmodium falciparum. J Biol Chem 2014; 289:30025-39. [PMID: 25204654 DOI: 10.1074/jbc.m114.586735] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The universally conserved kinase-associated endopeptidase 1 (Kae1) protein family has established roles in N(6)-threonylcarbamoyl adenosine tRNA modification, transcriptional regulation, and telomere homeostasis. These functions are performed in complex with a conserved core of protein binding partners. Herein we describe the localization, essentiality, and protein-protein interactions for Kae1 in the human malaria parasite Plasmodium falciparum. We found that the parasite expresses one Kae1 protein in the cytoplasm and a second protein in the apicoplast, a chloroplast remnant organelle involved in fatty acid, heme, and isoprenoid biosynthesis. To analyze the protein interaction networks for both Kae1 pathways, we developed a new proteomic cross-validation approach. This strategy compares immunoprecipitation-MS data sets across different cellular compartments to enrich for biologically relevant protein interactions. Our results show that cytoplasmic Kae1 forms a complex with Bud32 and Cgi121 as in other organisms, whereas apicoplast Kae1 makes novel interactions with multiple proteins in the apicoplast. Quantitative RT-PCR and immunoprecipitation studies indicate that apicoplast Kae1 and its partners interact specifically with the apicoplast ribosomes and with proteins involved in ribosome function. Together, these data indicate an expanded, apicoplast-specific role for Kae1 in the parasite.
Collapse
Affiliation(s)
- Jeremy P Mallari
- From the Departments of Medicine and Molecular Microbiology and the Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Anna Oksman
- From the Departments of Medicine and Molecular Microbiology and the Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Barbara Vaupel
- From the Departments of Medicine and Molecular Microbiology and the Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Daniel E Goldberg
- From the Departments of Medicine and Molecular Microbiology and the Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri 63110
| |
Collapse
|
5
|
Beck JR, Muralidharan V, Oksman A, Goldberg DE. PTEX component HSP101 mediates export of diverse malaria effectors into host erythrocytes. Nature 2014; 511:592-5. [PMID: 25043010 PMCID: PMC4130291 DOI: 10.1038/nature13574] [Citation(s) in RCA: 192] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 06/11/2014] [Indexed: 12/02/2022]
Affiliation(s)
- Josh R Beck
- 1] Department of Molecular Microbiology, Washington University School of Medicine, St Louis, Missouri 63110, USA [2]
| | - Vasant Muralidharan
- 1] Department of Medicine, Washington University School of Medicine, St Louis, Missouri 63110, USA [2] Howard Hughes Medical Institute, Washington University School of Medicine, St Louis, Missouri 63110, USA [3] [4] Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia 30602, USA
| | - Anna Oksman
- 1] Department of Molecular Microbiology, Washington University School of Medicine, St Louis, Missouri 63110, USA [2] Department of Medicine, Washington University School of Medicine, St Louis, Missouri 63110, USA [3] Howard Hughes Medical Institute, Washington University School of Medicine, St Louis, Missouri 63110, USA
| | - Daniel E Goldberg
- 1] Department of Molecular Microbiology, Washington University School of Medicine, St Louis, Missouri 63110, USA [2] Department of Medicine, Washington University School of Medicine, St Louis, Missouri 63110, USA [3] Howard Hughes Medical Institute, Washington University School of Medicine, St Louis, Missouri 63110, USA
| |
Collapse
|
6
|
Abstract
The Plasmodium falciparum genome encodes a single calpain. By generating P. falciparum clones expressing C-terminally tagged calpain, we localized this protein to the nucleolus. Pf_calpain possesses an unusual and long N-terminal domain in which we identified three subregions that are highly conserved among Plasmodium species. Two have putative targeting signals: a myristoylation motif and a nuclear localization sequence. We assessed their functionality. Our data show that the nuclear localization sequence is an active nuclear import motif that contains an embedded signal conferring nucleolar localization on various chimeras. The N-terminus is myristoylated at Gly2 and palmitoylated at Cys3 and Cys22. Palmitoylation status has an important role in dictating P. falciparum calpain localization. The targeting signals function in mammalian cells as well as in the parasite. P. falciparum calpain is a unique nucleolar protein with an interesting mechanism of targeting.
Collapse
Affiliation(s)
- Ilaria Russo
- Howard Hughes Medical Institute, Washington University School of Medicine, Department of Molecular Microbiology, St Louis, Missouri 63110, USA
| | | | | |
Collapse
|
7
|
Proust J, Oksman A, Charissoux JL, Mabit C, Arnaud JP. [Intra-articular fracture of the distal humerus: outcome after osteosynthesis in patients over 60]. ACTA ACUST UNITED AC 2008; 93:798-806. [PMID: 18166952 DOI: 10.1016/s0035-1040(07)78463-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
PURPOSE OF THE STUDY This is a retrospective analysis of patients aged over 60 years treated in a single center for intra-articular fractures of the distal humerus. Outcomes were compared with published results for osteosynthesis and arthroplasty. MATERIAL AND METHODS The cohort included 34 patients (36 fractures) reviewed at mean 35 months. Mean age was 77.6 years. Fracture types were: C1: 8, C2: 10, C3: 18. The transtricipital posteromedial approach was used in the majority of patients. Fixation was achieved with a prebent lateral plate (n=11 fractures), a Y-plate (n=9), two plates (n=4), pins or screws (n=9) and an external fixator (n=3). Outcome was assessed with the Mayo elbow score, the Bröberg radiographic score and patient satisfaction. The social impact was also noted. RESULTS The mean Mayo elbow score was 73.3; outcome was excellent (n=13), good (n=8), fair (n=5) and poor (n=10). Pain persisted in 23 patients. The mean range of movement was 80 degrees . Patient satisfaction remained good. Ten patients did not recover their preoperative level of autonomy. Radiological signs of osteoarthritis were noted for 75% of patients and nonunion of the humeral fracture in 32%. There were three superficial infections and four neurological lesions. DISCUSSION Good and very good outcome was noted for 59% of the osteosyntheses in this series, compared with 71% in the literature. The rate for arthroplasty is 95%. The mean range of motion is 101 degrees , 17% of patients with a prosthesis complain of pain, 5% develop a superficial infection and 6.5% suffer neurological injury. The estimated rate of revision for arthroplasty is 11% at 7 years. CONCLUSION Beyond the age of 65 years and based on evidence reported in the literature, it would be advisable to prefer another mode of treatment for these intra-articular fractures, for example elbow arthroplasty, particularly for comminutive fractures on osteoporotic bone.
Collapse
Affiliation(s)
- J Proust
- Département d'Orthopédie Traumatologie, Hôpital Universitaire Dupuytren, 2, avenue Martin Luther King, 87042 Limoges cedex.
| | | | | | | | | |
Collapse
|
8
|
Denes E, Boumediene A, Durox H, Oksman A, Saint-Marcoux F, Darde ML, Gaulier JM. Voriconazole concentrations in synovial fluid and bone tissues. J Antimicrob Chemother 2007; 59:818-9. [PMID: 17329266 DOI: 10.1093/jac/dkm023] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
9
|
Mabit C, Gougam T, Thomazeau H, Ingels A, Andrieux M, Veillard D, Coste C, Oksman A, Proust J, Rochwerger A, Villalba M, Madougou S. Méthodologie et étude épidémiologique. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/s0035-1040(06)75856-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
10
|
Mabit C, Gougam T, Thomazeau H, Ingels A, Andrieux M, Veillard D, Coste C, Oksman A, Proust J, Rochwerger A, Villalba M, Madougou S. [Periprosthetic fractures around total hip and knee arthroplasty. Methodology and epidemiologic study]. Rev Chir Orthop Reparatrice Appar Mot 2006; 92:2S40-2S43. [PMID: 17802654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Affiliation(s)
- C Mabit
- Département de Chirurgie Orthopédique et Traumatologique, CHU Dupuytren, 2, avenue, Martin-Luther-King, 87042 Limoges
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Ocheskey JA, Harpstrite SE, Oksman A, Goldberg DE, Sharma V. Metalloantimalarials: synthesis and characterization of a novel agent possessing activity against Plasmodium falciparum. Chem Commun (Camb) 2005:1622-4. [PMID: 15770280 DOI: 10.1039/b415771k] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The synthesis, characterization, and antimalarial potency of an amine-phenol complex of gallium(III), [{1,12-bis(2-hydroxy-3-methoxy-5-(quinolin-3-yl)-benzyl)-1,5,8,12-tetraazadodecane}-gallium(III)]+, [Ga-3-M-5-Quadd]+ (7) is described; a novel agent that targets Plasmodium falciparum strains.
Collapse
Affiliation(s)
- Joseph A Ocheskey
- Mallinckrodt Institute of Radiology, Washington University Medical School, St. Louis, MO, USA
| | | | | | | | | |
Collapse
|
12
|
Okunade AL, Bikoff RE, Casper SJ, Oksman A, Goldberg DE, Lewis WH. Antiplasmodial activity of extracts and quassinoids isolated from seedlings of Ailanthus altissima (Simaroubaceae). Phytother Res 2003; 17:675-7. [PMID: 12820239 DOI: 10.1002/ptr.1336] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Extracts and isolated compounds from seedlings of Ailanthus altissima, were assessed for antiplasmodial activity in vitro. Two quassinoids, ailanthone and 6alpha-tigloyloxychaparrinone, isolated from the active extracts showed activity against both chloroquine-resistant and chloroquine-sensitive strains of Plasmodium falciparum in vitro. Only ailanthone demonstrated low toxicity against the Vero cell line (kidney cells from the African green monkey). This is the first report of the isolation and antiplasmodial activity of 6alpha-tigloyloxychaparrinone from this species.
Collapse
Affiliation(s)
- Adewole L Okunade
- Department of Biology, Washington University in St Louis, MO 63130, USA.
| | | | | | | | | | | |
Collapse
|
13
|
Harpstrite SE, Beatty AA, Collins SD, Oksman A, Goldberg DE, Sharma V. Metalloantimalarials: targeting of P. falciparum strains with novel iron(III) and gallium(III) complexes of an amine phenol ligand. Inorg Chem 2003; 42:2294-300. [PMID: 12665363 DOI: 10.1021/ic034036e] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Emergence of chloroquine (CQ)-resistant Plasmodium falciparum strains necessitates discovery of potent and inexpensive antimalarial drugs. The high cost of new drugs negatively impacts their access and distribution in the regions of the world with scarce economic resources. While exploring structure-activity relationships, using gallium(III) as a surrogate marker for iron(III), we found cationic, and moderately hydrophobic, compounds, [[1,12-bis(2-hydroxy-3-ethyl-benzyl)-1,5,8,12-tetraazadodecane]metal(III)](+) (metal = Fe(III) and Ga(III); [Fe-3-Eadd](+), 3; [Ga-3-Eadd](+), 4), that possessed antimalarial activity. Crystal structure analyses revealed octahedral geometry for these complexes. The RP-HPLC analysis, after incubation in PBS or HEPES buffer (pH 7.4) at 37 degrees C for 3 days, detected only parental compounds thereby providing evidence for stability under physiological conditions. Both 3 and 4 demonstrated promising half-maximum inhibitory concentration (IC(50)) values of approximately 80 and 86 nM in the CQ-sensitive HB-3 line, respectively. However, both 3 and 4 were found to possess elevated IC(50) values of 2.5 and 0.8 microM, respectively, in the CQ-resistant Dd2 line, thus displaying preferential cytotoxicity toward the CQ-sensitive HB3 line. In cultured parasites, 3 and 4 targeted hemozoin formation. Thus, these compounds acted similarly to chloroquine with regard to action and resistance, despite the lack of structural similarity to quinolines. Finally, similarity in coordination chemistry, stability, and antimalarial cytotoxicity profiles indicated that gallium(III) ion can serve as a template for iron(III) in structure elucidation of active molecules in solution.
Collapse
Affiliation(s)
- Scott E Harpstrite
- Mallinckrodt Institute of Radiology, Washington University Medical School, Box 8225, 510 S. Kingshighway Blvd., St. Louis, Missouri 63110, USA
| | | | | | | | | | | |
Collapse
|
14
|
|
15
|
Ocheskey JA, Polyakov VR, Harpstrite SE, Oksman A, Goldberg DE, Piwnica-Worms D, Sharma V. Synthesis, characterization, and molecular structure of a gallium(III) complex of an amine-phenol ligand with activity against chloroquine-sensitive Plasmodium falciparum strains. J Inorg Biochem 2003; 93:265-70. [PMID: 12576290 DOI: 10.1016/s0162-0134(02)00592-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Emergence of chloroquine-resistant Plasmodium falciparum strains necessitates discovery of novel antimalarial drugs, especially if the agents can be synthesized from commercially available, inexpensive precursors via short synthetic routes. While exploring structure-activity relationships, we found a gallium(III) complex, [(1,12-bis(2-hydroxy-5-methoxybenzyl)-1,5,8,12-tetraazadodecane)-gallium(III)](+) [Ga-5-Madd](+), 1, that possessed antimalarial efficacy. Like previously reported complexes, the crystal structure of 1 revealed gallium(III) in a symmetrical octahedral environment surrounded by four secondary amine nitrogen atoms in equatorial plane and two axial oxygen atoms. In contrast to a previously reported complex, [Ga-3-Madd](+), this novel metallo-antimalarial 1 possessed modest efficacy against chloroquine-sensitive HB3 Plasmodium lines. Thus, slight variation in the positions of methoxy functionalities on the aromatic rings of the organic scaffold dramatically altered specificity thereby suggesting a targeted (e.g., transporter- or receptor-mediated) rather than non-specific (e.g., pH or other gradient-mediated) mechanism of action for these agents.
Collapse
Affiliation(s)
- Joseph A Ocheskey
- Mallinckrodt Institute of Radiology, Washington University Medical School, St. Louis, MO 63110, USA
| | | | | | | | | | | | | |
Collapse
|
16
|
Akompong T, Kadekoppala M, Harrison T, Oksman A, Goldberg DE, Fujioka H, Samuel BU, Sullivan D, Haldar K. Trans expression of a Plasmodium falciparum histidine-rich protein II (HRPII) reveals sorting of soluble proteins in the periphery of the host erythrocyte and disrupts transport to the malarial food vacuole. J Biol Chem 2002; 277:28923-33. [PMID: 12023959 DOI: 10.1074/jbc.m201968200] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The heme polymer hemozoin is produced in the food vacuole (fv) of the parasite after hemoglobin proteolysis and is the target of the drug chloroquine. A candidate heme polymerase, the histidine-rich protein II (HRPII), is proposed to be delivered to the fv by ingestion of the infected-red cell cytoplasm. Here we show that 97% of endogenous Plasmodium falciparum (Pf) HRPII (PfHRPII) is secreted as soluble protein in the periphery of the red cell and avoids endocytosis by the parasite, and 3% remains membrane-bound within the parasite. Transfected cells release 90% of a soluble transgene PfHRPIImyc into the red cell periphery and contain 10% membrane bound within the parasite. Yet these cells show a minor reduction in hemozoin production and IC(50) for chloroquine. They also show decreased transport of resident fv enzyme PfPlasmepsin I, the endoplasmic reticulum (ER) marker PfBiP, and parasite-associated HRPII to fvs. Instead, all three proteins accumulate in the ER, although there is no defect in protein export from the parasite. The data suggest that novel mechanisms of sorting (i) soluble antigens like HRPII in the red cell cytoplasm and (ii) fv-bound membrane complexes in the ER regulate parasite digestive processes.
Collapse
Affiliation(s)
- Thomas Akompong
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Carreiro M, Sailler L, Dahan S, Oksman A, Oilier S, Arlet P. Artérite temporale juvénile : une maladie bénigne. Rev Med Interne 2001. [DOI: 10.1016/s0248-8663(01)80219-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
18
|
Salmon BL, Oksman A, Goldberg DE. Malaria parasite exit from the host erythrocyte: A two-step process requiring extraerythrocytic proteolysis. Proc Natl Acad Sci U S A 2001; 98:271-6. [PMID: 11114161 PMCID: PMC14580 DOI: 10.1073/pnas.98.1.271] [Citation(s) in RCA: 132] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Intraerythrocytic malaria parasites replicate by the process of schizogeny, during which time they copy their genetic material and package it into infective merozoites. These merozoites must then exit the host cell to invade new erythrocytes. To better characterize the events of merozoite escape, erythrocytes containing Plasmodium falciparum schizonts were cultured in the presence of the cysteine protease inhibitor, l-transepoxy-succinyl-leucylamido-(4-guanidino)butane (E64). This treatment resulted in the accumulation of extraerythrocytic merozoites locked within a thin, transparent membrane. Immunomicroscopy demonstrated that the single membrane surrounding the merozoites is not erythrocytic but rather is derived from the parasitophorous vacuolar membrane (PVM). Importantly, structures identical in appearance can be detected in untreated cultures at low frequency. Further studies revealed that (i) merozoites from the PVM-enclosed merozoite structures (PEMS) are invasive, viable, and capable of normal development; (ii) PEMS can be purified easily and efficiently; and (iii) when PEMS are added to uninfected red blood cells, released merozoites can establish a synchronous wave of infection. These observations suggest that l-transepoxy-succinyl-leucylamido-(4-guanidino)butane (E64) causes an accumulation of an intermediate normally present during the process of rupture. We propose a model for the process of rupture: merozoites enclosed within the PVM first exit from the host erythrocyte and then rapidly escape from the PVM by a proteolysis-dependent mechanism.
Collapse
Affiliation(s)
- B L Salmon
- Howard Hughes Medical Institute, Departments of Molecular Medicine and Microbiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | | | | |
Collapse
|
19
|
Mamoun CB, Truong R, Gluzman I, Akopyants NS, Oksman A, Goldberg DE. Transfer of genes into Plasmodium falciparum by polyamidoamine dendrimers. Mol Biochem Parasitol 1999; 103:117-21. [PMID: 10514088 DOI: 10.1016/s0166-6851(99)00116-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- C B Mamoun
- Howard Hughes Medical Institute, Washington University School of Medicine, Department of Molecular Microbiology, St. Louis, MO 63110, USA
| | | | | | | | | | | |
Collapse
|
20
|
Carroll CD, Patel H, Johnson TO, Guo T, Orlowski M, He ZM, Cavallaro CL, Guo J, Oksman A, Gluzman IY, Connelly J, Chelsky D, Goldberg DE, Dolle RE. Identification of potent inhibitors of Plasmodium falciparum plasmepsin II from an encoded statine combinatorial library. Bioorg Med Chem Lett 1998; 8:2315-20. [PMID: 9873534 DOI: 10.1016/s0960-894x(98)00419-3] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
An encoded 13,020-member combinatorial library was synthesized containing a statine core. Evaluation of this library with plasmepsin II, an aspartyl protease required for hemoglobin metabolism in the malaria parasite, led to the identification of potent and selective inhibitors as well as novel structure-activity relationships.
Collapse
Affiliation(s)
- C D Carroll
- Department of Biology, Pharmacopeia, Inc., Princeton, NJ 08540, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Goldberg DE, Sharma V, Oksman A, Gluzman IY, Wellems TE, Piwnica-Worms D. Probing the chloroquine resistance locus of Plasmodium falciparum with a novel class of multidentate metal(III) coordination complexes. J Biol Chem 1997; 272:6567-72. [PMID: 9045684 DOI: 10.1074/jbc.272.10.6567] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The malaria organism Plasmodium falciparum detoxifies heme released during degradation of host erythrocyte hemoglobin by sequestering it within the parasite digestive vacuole as a polymer called hemozoin. Antimalarial agents such as chloroquine appear to work by interrupting the heme polymerization process, but their efficacy has been impaired by the emergence of drug-resistant organisms. We report here the identification of a new class of antimalarial compounds, hexadentate ethylenediamine-N, N'-bis[propyl(2-hydroxy-(R)-benzylimino)]metal(III) complexes [(R)-ENBPI-M(III)] and a corresponding ((R)-benzylamino)] analog [(R)-ENBPA-M(III)], a group of lipophilic monocationic leads amenable to metallopharmaceutical development. Racemic mixtures of Al(III), Fe(III), or Ga(III) but not In(III) (R)-ENBPI metallo-complexes killed intraerythrocytic malaria parasites in a stage-specific manner, the R = 4,6-dimethoxy-substituted ENBPI Fe(III) complex being most potent (IC50 approximately 1 microM). Inhibiting both chloroquine-sensitive and -resistant parasites, potency of these imino complexes correlated in a free metal-independent manner with their ability to inhibit heme polymerization in vitro. In contrast, the reduced (amino) 3-MeO-ENBPA Ga(III) complex (MR045) was found to be selectively toxic to chloroquine-resistant parasites in a verapamil-insensitive manner. In 21 independent recombinant progeny of a genetic cross, susceptibility to this agent mapped in perfect linkage with the chloroquine resistance phenotype suggesting that a locus for 3-MeO-ENBPA Ga(III) susceptibility was located on the same 36-kilobase segment of chromosome 7 as the chloroquine resistance determinant. These compounds may be useful as novel probes of chloroquine resistance mechanisms and for antimalarial drug development.
Collapse
Affiliation(s)
- D E Goldberg
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | | | | | | | | | | |
Collapse
|
22
|
Francis SE, Gluzman IY, Oksman A, Banerjee D, Goldberg DE. Characterization of native falcipain, an enzyme involved in Plasmodium falciparum hemoglobin degradation. Mol Biochem Parasitol 1996; 83:189-200. [PMID: 9027752 DOI: 10.1016/s0166-6851(96)02772-7] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In Plasmodium falciparum, a cysteine protease known as falcipain has been implicated in the essential metabolic process of hemoglobin degradation. Parallel lines of investigation, using native or recombinant enzyme, have led to differing conclusions about the specificity and role of this protease. We have now determined that (1) Native falcipain does not cleave hemoglobin unless this substrate has first been denatured by reducing agents, acid-acetone treatment or plasmepsin action. (2) Reducing agents such as glutathione cannot denature hemoglobin in the presence of catalase, which is accumulated in the digestive vacuole. (3) The purified native enzyme has kinetics similar to those obtained with trophozoite extract, but substantially different from those of recombinant enzyme. (4) Although there are numerous cysteine protease genes in the P. falciparum genome, the falcipain gene is the only one whose transcript can be detected in the early intraerythrocytic parasites. We conclude that falcipain likely works by degrading hemoglobin fragments after initial aspartic protease attack has denatured the substrate. We propose that falcipain inhibitors block the initial steps of degradation indirectly by promoting vacuolar accumulation of osmotically active hemoglobin peptides.
Collapse
Affiliation(s)
- S E Francis
- Howard Hughes Medical Institute, Department of Molecular Microbiology, St. Louis, Missouri 63110, USA
| | | | | | | | | |
Collapse
|
23
|
Silva AM, Lee AY, Gulnik SV, Maier P, Collins J, Bhat TN, Collins PJ, Cachau RE, Luker KE, Gluzman IY, Francis SE, Oksman A, Goldberg DE, Erickson JW. Structure and inhibition of plasmepsin II, a hemoglobin-degrading enzyme from Plasmodium falciparum. Proc Natl Acad Sci U S A 1996; 93:10034-9. [PMID: 8816746 PMCID: PMC38331 DOI: 10.1073/pnas.93.19.10034] [Citation(s) in RCA: 191] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Plasmodium falciparum is the major causative agent of malaria, a disease of worldwide importance. Resistance to current drugs such as chloroquine and mefloquine is spreading at an alarming rate, and our antimalarial armamentarium is almost depleted. The malarial parasite encodes two homologous aspartic proteases, plasmepsins I and II, which are essential components of its hemoglobin-degradation pathway and are novel targets for antimalarial drug development. We have determined the crystal structure of recombinant plasmepsin II complexed with pepstatin A. This represents the first reported crystal structure of a protein from P. falciparum. The crystals contain molecules in two different conformations, revealing a remarkable degree of interdomain flexibility of the enzyme. The structure was used to design a series of selective low molecular weight compounds that inhibit both plasmepsin II and the growth of P. falciparum in culture.
Collapse
Affiliation(s)
- A M Silva
- Structural Biochemistry Program, National Cancer Institute/SAIC, Frederick, MD 21702, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Silva AM, Lee AY, Gulnik SV, Majer P, Collins J, Bhat TN, Collins PJ, Cachau RE, Luker KE, Gluzman IY, Francis SE, Oksman A, Goldberg DE, Erickson JW. Structure and inhibition of plasmepsin II, a hemoglobin-degrading enzyme from P. Falciparum. Acta Crystallogr A 1996. [DOI: 10.1107/s0108767396091088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
|
25
|
Gluzman IY, Francis SE, Oksman A, Smith CE, Duffin KL, Goldberg DE. Order and specificity of the Plasmodium falciparum hemoglobin degradation pathway. J Clin Invest 1994; 93:1602-8. [PMID: 8163662 PMCID: PMC294190 DOI: 10.1172/jci117140] [Citation(s) in RCA: 228] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The human malaria parasite, Plasmodium falciparum, degrades nearly all its host cell hemoglobin during a short segment of its intraerythrocytic development. This massive catabolic process occurs in an acidic organelle, the digestive vacuole. Aspartic and cysteine proteases have been implicated in this pathway. We have isolated three vacuolar proteases that account for most of the globin-degrading activity of the digestive vacuole. One is the previously described aspartic hemoglobinase that initiates hemoglobin degradation. A second aspartic protease is capable of cleaving hemoglobin with an overlapping specificity, but seems to prefer acid-denatured globin. The third is a cysteine protease that does not recognize native hemoglobin but readily cleaves denatured globin. It is synergistic with the aspartic hemoglobinase, both by in vitro assay of hemoglobin degradation, and by isobologram analysis of protease inhibitor-treated parasites in culture. The cysteine protease is highly sensitive to chloroquine-heme complex, suggesting a possible mechanism of 4-aminoquinoline antimalarial action. The data suggest an ordered pathway of hemoglobin catabolism that presents an excellent target for chemotherapy.
Collapse
Affiliation(s)
- I Y Gluzman
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri 63110
| | | | | | | | | | | |
Collapse
|
26
|
Francis SE, Gluzman IY, Oksman A, Knickerbocker A, Mueller R, Bryant ML, Sherman DR, Russell DG, Goldberg DE. Molecular characterization and inhibition of a Plasmodium falciparum aspartic hemoglobinase. EMBO J 1994; 13:306-17. [PMID: 8313875 PMCID: PMC394809 DOI: 10.1002/j.1460-2075.1994.tb06263.x] [Citation(s) in RCA: 218] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Intraerythrocytic malaria parasites rapidly degrade virtually all of the host cell hemoglobin. We have cloned the gene for an aspartic hemoglobinase that initiates the hemoglobin degradation pathway in Plasmodium falciparum. It encodes a protein with 35% homology to human renin and cathepsin D, but has an unusually long pro-piece that includes a putative membrane spanning anchor. Immunolocalization studies place the enzyme in the digestive vacuole and throughout the hemoglobin ingestion pathway, suggesting an unusual protein targeting route. A peptidomimetic inhibitor selectively blocks the aspartic hemoglobinase, prevents hemoglobin degradation and kills the organism. We conclude that Plasmodium hemoglobin catabolism is a prime target for antimalarial chemotherapy and have identified a lead compound towards this goal.
Collapse
Affiliation(s)
- S E Francis
- Department of Molecular Microbiology, Washington University School of Medicine, St Louis, MO
| | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Willis I, Oksman A, López-De-León A. The PCF1-1 mutation increases the activity of the transcription factor (TF) IIIB fraction from Saccharomyces cerevisiae. Nucleic Acids Res 1992; 20:3725-30. [PMID: 1641338 PMCID: PMC334024 DOI: 10.1093/nar/20.14.3725] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
PCF1-1 is a dominant suppressor of a tRNA gene A block promoter mutation (A19) in Saccharomyces cerevisiae. Transcriptional activation by PCF1-1 was examined in vitro using whole-cell extracts and purified factors derived from mutant and wild-type strains. These experiments show that PCF1 is a general activator of RNA polymerase III (pol III) gene transcription. The transcription of all pol III genes analyzed to date, including type I and numerous type II genes, is increased 3-7 fold in mutant cell extracts. Single round transcription assays indicate that the PCF1-1 mutation increases the number of functional preinitiation complexes and suggest that this is achieved by increasing the intrinsic activity of the encoded product rather than its amount. Point mutations throughout the A block of the sup3-e gene and numerous B block mutations fail to abolish transcriptional activation suggesting that interactions between TFIIIC and the internal promoter are unaffected by PCF1-1. Moreover, TFIIIC purified from the mutant strain is incapable of conferring PCF1-1 transcriptional activity to a reaction in which the remaining components are wild-type. In contrast, the activity of the TFIIIB fraction is increased in PCF1-1 extracts and can reconstitute mutant levels of transcription when added to wild-type TFIIIC and polymerase. We conclude that PCF1 is a component or regulator of TFIIIB.
Collapse
Affiliation(s)
- I Willis
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461
| | | | | |
Collapse
|
28
|
Ane P, de Firmas JL, Oksman A, Roisan J. [A voluminous mediastinal tumor can be excised by cervicotomy]. J Fr Otorhinolaryngol Audiophonol Chir Maxillofac 1984; 33:49-51. [PMID: 6699617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
|