Effect of Quinine Treatment of the Host upon the Carbohydrate Metabolism of the Malarial Parasite Plasmodium Gallinaceum

We have identified a gene that encodes the polypeptide cytochrome b in the avian malarial parasite Plasmodium gallinaceum. The gene containing the open reading frame was found to be located on a 6.2-kilobase multimeric extrachromosomal element. The amino acid translation from this gene demonstrated significant similarities to cytochrome b sequences from yeast, mammal, and fungus genomes. We present evidence that the P. gallinaceum cytochrome b transcript is part of a larger primary transcript from the element that is subsequently processed. The message for P. gallinaceum cytochrome b was found to be 1.2 kilobases in size. This is the first report identifying a mitochondrial nucleic acid sequence in malaria-causing organisms and suggests that a functional cytochrome system may exist in these parasites.

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Inhibition of Pyruvate Oxidation in the Malarial Parasite Plasmodium Gallinaceum by Quinine Treatment of the Host

The Journal of Infectious Diseases ◽

10.1093/infdis/85.2.195 ◽

1949 ◽

Vol 85 (2) ◽

pp. 195-204 ◽

Cited By ~ 10

Author(s):

J. W. Moulder

Keyword(s):

Malarial Parasite ◽

Plasmodium Gallinaceum ◽

Pyruvate Oxidation ◽

Parasite Plasmodium

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Characterization of a conserved extrachromosomal element isolated from the avian malarial parasite Plasmodium gallinaceum

Molecular and Cellular Biology ◽

10.1128/mcb.9.9.3621-3629.1989 ◽

1989 ◽

Vol 9 (9) ◽

pp. 3621-3629

Author(s):

J T Joseph ◽

S M Aldritt ◽

T Unnasch ◽

O Puijalon ◽

D F Wirth

Keyword(s):

Repeat Unit ◽

Unit Length ◽

Malarial Parasite ◽

Pulse Field ◽

Plasmodium Gallinaceum ◽

Multiple Transcripts ◽

Parasite Plasmodium ◽

Extrachromosomal Element ◽

Repeat Unit Length

We have identified a conserved, repeated, and highly transcribed DNA element from the avian malarial parasite Plasmodium gallinaceum. The element produced multiple transcripts in both zygotes and asexual blood stages of this parasite. It was found to be highly conserved in all of five malarial species tested and hybridized at reduced stringency to other members of the phylum Apicomplexa, including the genera Babesia, Eimeria, Toxoplasma, and Theileria. The copy number of the element was about 15, and it had a circularly permuted restriction map with a repeat unit length of about 6.2 kilobases. It could be separated from the main genomic DNA by using sucrose gradients and agarose gels, and it migrated separately from the recognized Plasmodium chromosomes on pulse-field gels. In the accompanying paper (S. M. Aldritt, J. T. Joseph, and D. F. Wirth, Mol. Cell. Biol. 9:3614-3620, 1989), evidence is presented that element contains the mitochondrial genes for the protein cytochrome b and a fragment of the large rRNA. We postulate that this element is an episome in the mitochondria of the obligate parasites belonging to the phylum Apicomplexa.

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Characterization of a conserved extrachromosomal element isolated from the avian malarial parasite Plasmodium gallinaceum.

Molecular and Cellular Biology ◽

10.1128/mcb.9.9.3621 ◽

1989 ◽

Vol 9 (9) ◽

pp. 3621-3629 ◽

Cited By ~ 39

Author(s):

J T Joseph ◽

S M Aldritt ◽

T Unnasch ◽

O Puijalon ◽

D F Wirth

Keyword(s):

Repeat Unit ◽

Unit Length ◽

Malarial Parasite ◽

Pulse Field ◽

Plasmodium Gallinaceum ◽

Multiple Transcripts ◽

Parasite Plasmodium ◽

Extrachromosomal Element ◽

Repeat Unit Length

We have identified a conserved, repeated, and highly transcribed DNA element from the avian malarial parasite Plasmodium gallinaceum. The element produced multiple transcripts in both zygotes and asexual blood stages of this parasite. It was found to be highly conserved in all of five malarial species tested and hybridized at reduced stringency to other members of the phylum Apicomplexa, including the genera Babesia, Eimeria, Toxoplasma, and Theileria. The copy number of the element was about 15, and it had a circularly permuted restriction map with a repeat unit length of about 6.2 kilobases. It could be separated from the main genomic DNA by using sucrose gradients and agarose gels, and it migrated separately from the recognized Plasmodium chromosomes on pulse-field gels. In the accompanying paper (S. M. Aldritt, J. T. Joseph, and D. F. Wirth, Mol. Cell. Biol. 9:3614-3620, 1989), evidence is presented that element contains the mitochondrial genes for the protein cytochrome b and a fragment of the large rRNA. We postulate that this element is an episome in the mitochondria of the obligate parasites belonging to the phylum Apicomplexa.

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Sequence identification of cytochrome b in Plasmodium gallinaceum

Molecular and Cellular Biology ◽

10.1128/mcb.9.9.3614-3620.1989 ◽

1989 ◽

Vol 9 (9) ◽

pp. 3614-3620

Author(s):

S M Aldritt ◽

J T Joseph ◽

D F Wirth

Keyword(s):

Cytochrome B ◽

Open Reading Frame ◽

Malarial Parasite ◽

Plasmodium Gallinaceum ◽

Primary Transcript ◽

Present Evidence ◽

Reading Frame ◽

Sequence Identification ◽

Parasite Plasmodium ◽

Extrachromosomal Element

We have identified a gene that encodes the polypeptide cytochrome b in the avian malarial parasite Plasmodium gallinaceum. The gene containing the open reading frame was found to be located on a 6.2-kilobase multimeric extrachromosomal element. The amino acid translation from this gene demonstrated significant similarities to cytochrome b sequences from yeast, mammal, and fungus genomes. We present evidence that the P. gallinaceum cytochrome b transcript is part of a larger primary transcript from the element that is subsequently processed. The message for P. gallinaceum cytochrome b was found to be 1.2 kilobases in size. This is the first report identifying a mitochondrial nucleic acid sequence in malaria-causing organisms and suggests that a functional cytochrome system may exist in these parasites.

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THE TRANSFORMATION OF THE PLASMODIUM GALLINACEUM OOCYST IN AEDES AEGYPTI MOSQUITOES

The Journal of Cell Biology ◽

10.1083/jcb.34.1.311 ◽

1967 ◽

Vol 34 (1) ◽

pp. 311-326 ◽

Cited By ~ 53

Author(s):

John A. Terzakis ◽

Helmuth Sprinz ◽

Ronald A. Ward

Keyword(s):

Aedes Aegypti ◽

Malarial Parasite ◽

Plasmodium Gallinaceum ◽

Dense Area ◽

Cytoplasmic Inclusions ◽

Parasite Plasmodium ◽

Membrane Bound ◽

Cleft Formation ◽

Cellular Components ◽

Single Mitochondrion

Sporoblast and sporozoite formation from oocysts of the avian malarial parasite, Plasmodium gallinaceum, after the seventh day of infection in Aedes aegypti mosquitoes offers an interesting example of differentiation involving the appearance and modification of several cellular components. Sporoblast formation is preceded by (a) invaginations of the oocyst capsule into the oocyst cytoplasm, (b) subcapsular vacuolization and cleft formation, (c) the appearance of small tufts of capsule material on the previously noted invaginations, and (d) linear dense areas located just below the oocyst plasma membrane which predetermine the site of emerging sporozoites from the sporoblast. The subcapsular clefts subdivide the once-solid oocyst into sporoblast peninsulae. Within the sporoblast, nuclei migrate from the random distribution seen in the solid oocyst and come to lie at the periphery of the sporoblast just below the linear dense areas noted in the earlier stage. A typical nuclear fiber apparatus occurs in most of the nuclei seen in random sections at this stage although such a fiber apparatus may occasionally be seen in the solid oocyst stage. The nucleus, its associated fiber apparatus, and the overlying dense area appear to induce the onset of sporozoite budding from the sporoblast as well as the formation of the sporozoite pellicular complex and the paired organelle precursor. Several mitochondria are present in each sporozoite, in contrast to the single mitochondrion seen in the merozoites of the erythrocytic and exoerythrocytic stages of avian malaria infection. The paired organelles and associated dense inclusion bodies are formed by condensation of an irregular meshwork of membrane-bound, coarse, dense material. The nature of small, particulate cytoplasmic inclusions is described.

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Orotidylate-metabolizing enzymes of the human malarial parasite, Plasmodium falciparum, differ from host cell enzymes.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)32795-9 ◽

1983 ◽

Vol 258 (5) ◽

pp. 2852-2855

Author(s):

P K Rathod ◽

P Reyes

Keyword(s):

Plasmodium Falciparum ◽

Host Cell ◽

Malarial Parasite ◽

Metabolizing Enzymes ◽

Parasite Plasmodium ◽

Parasite Plasmodium Falciparum

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Localization of ferrochelatase in Plasmodium falciparum

Biochemical Journal ◽

10.1042/bj20040952 ◽

2004 ◽

Vol 384 (2) ◽

pp. 429-436 ◽

Cited By ~ 35

Author(s):

Sundaramurthy VARADHARAJAN ◽

B. K. Chandrashekar SAGAR ◽

Pundi N. RANGARAJAN ◽

Govindarajan PADMANABAN

Keyword(s):

Plasmodium Falciparum ◽

De Novo ◽

Enzymic Activity ◽

Malarial Parasite ◽

Parasite Genome ◽

Marker Proteins ◽

Parasite Plasmodium ◽

Theoretical Predictions ◽

Parasite Plasmodium Falciparum

Our previous studies have demonstrated de novo haem biosynthesis in the malarial parasite (Plasmodium falciparum and P. berghei). It has also been shown that the first enzyme of the pathway is the parasite genome-coded ALA (δ-aminolaevulinate) synthase localized in the parasite mitochondrion, whereas the second enzyme, ALAD (ALA dehydratase), is accounted for by two species: one species imported from the host red blood cell into the parasite cytosol and another parasite genome-coded species in the apicoplast. In the present study, specific antibodies have been raised to PfFC (parasite genome-coded ferrochelatase), the terminal enzyme of the haem-biosynthetic pathway, using recombinant truncated protein. With the use of these antibodies as well as those against the hFC (host red cell ferrochelatase) and other marker proteins, immunofluorescence studies were performed. The results reveal that P. falciparum in culture manifests a broad distribution of hFC and a localized distribution of PfFC in the parasite. However, PfFC is not localized to the parasite mitochondrion. Immunoelectron-microscopy studies reveal that PfFC is indeed localized to the apicoplast, whereas hFC is distributed in the parasite cytoplasm. These results on the localization of PfFC are unexpected and are at variance with theoretical predictions based on leader sequence analysis. Biochemical studies using the parasite cytosolic and organellar fractions reveal that the cytosol containing hFC accounts for 80% of FC enzymic activity, whereas the organellar fraction containing PfFC accounts for the remaining 20%. Interestingly, both the isolated cytosolic and organellar fractions are capable of independent haem synthesis in vitro from [4-14C]ALA, with the cytosol being three times more efficient compared with the organellar fraction. With [2-14C]glycine, most of the haem is synthesized in the organellar fraction. Thus haem is synthesized in two independent compartments: in the cytosol, using the imported host enzymes, and in the organellar fractions, using the parasite genome-coded enzymes.

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