Studies on the Host—parasite Relationships of Untreated Infections With Plasmodium Lophurae in Ducks1

Hewitt, Redginal

doi:10.1093/oxfordjournals.aje.a118809

Cited by 16 publications

(9 citation statements)

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“…Very dense, large, spherical bodies about p in diametersand of the same density as the pigment granules may be found suspended free in the cytoplasm (Figs. 1-3, 5 , 6,8,9). Their number and location varies.…”

Section: Or Servat Ionsmentioning

confidence: 99%

Intracellular phagotrophy by malaria parasites: an electron microscope study of Plasmodium lophurae*

Rudzinska

Trager

1957

The Journal of Protozoology

115

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SUMMARY. An electron microscope study of thin sections of duck erythrocytes infected with Plasmodium lophurae revealed that the so‐called “residual body” is a food vacuole formed by invagination from the cytoplasm of the host cell. Several such food vacuoles may exist in a single parasite. Digestion of hemoglobin evidently proceeds only within these food vacuoles, since they are the only place in the parasite where the characteristic malarial pigment granules may be found. This finding changes the role ascribed to the residual body and gives a new concept of the feeding mechanisms in P. lophurae and other malaria parasites. The cytoplasm of the host is taken in by the parasite by phagotrophy and not only as previously assumed, by diffusion. The fine structure of P. lophurae shows all major components found in other protozoan and metazoan cells. Some of the organelles appear to have a much simpler structure connected probably with the highly specialized intracellular parasitic life.

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Section: Or Servat Ionsmentioning

confidence: 99%

Intracellular phagotrophy by malaria parasites: an electron microscope study of Plasmodium lophurae*

Rudzinska

Trager

1957

The Journal of Protozoology

115

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“…This parasite, if inoculated intravenously in sufficiently large numbers, produces very heavy infections in ducks (8,9) and in baby chicks, but only mild infections in older chickens (7,(10)(11)(12). The experimental animals were inoculated with an amount of heparinized blood from a heavily infected chicken or duck sufficiently large to permit an accurate parasite count to be made on a thin blood film prepared immediately after inoculation.…”

Section: Methodsmentioning

confidence: 99%

Influence of Biotin Upon Susceptibility to Malaria

1943

Nutrition Reviews

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“…The intraerythrocytic stages of the avian malarial parasite Plasmodium lophurae contain numerous cytoplasmic granules (1). The main chemical constituent of isolated granules was shown to migrate as a single polypeptide on polyacrylamide gels, and analysis of hydrolysates of the polypeptide showed five major constituent amino acids: 73% histidine, 7.5% proline, 7% alanine, 6% glutamic acid, and 2% aspartic acid (2).…”

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confidence: 99%

On primary structure and biosynthesis of histidine-rich polypeptide from malarial parasite Plasmodium lophurae.

Kilejian¹,

Liao²,

Trager³

1975

Proc. Natl. Acad. Sci. U.S.A.

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Experiments on the primary structure of a histidine-rich polypeptide isolated from the malarial parasite Plasmodium Jophurae indicate that the smaller quantities of amino acids other than histidine form an integral part of the polypeptide and do not arise from a protein contaminating a histidine homopolymer. In culture, the parasites incorporate over 50% of exogenously supplied histidine into the histidine-rich polypeptide and this incorporation is inhibited by puromycin.The intraerythrocytic stages of the avian malarial parasite Plasmodium lophurae contain numerous cytoplasmic granules (1). The main chemical constituent of isolated granules was shown to migrate as a single polypeptide on polyacrylamide gels, and analysis of hydrolysates of the polypeptide showed five major constituent amino acids: 73% histidine, 7.5% proline, 7% alanine, 6% glutamic acid, and 2% aspartic acid (2). The unusually high content of histidine raised two questions: (a) could the smaller quantities of other amino acids come from a typical protein isolated as a contaminant with the histidine homopolymer rather than being integral parts of the polypeptide, and (b) could the polypeptide possibly be synthesized by a non-ribosomal enzymatic system (3-5). Even though non-ribosomal synthesis of peptides has been shown only in prokaryotes, the possibility that it might also exist in eukaryotes cannot be excluded. The unusually high content of one amino acid, histidine, and some parallelism with the polypeptide of the cyanophycin granules of blue-green algae made the malaria polypeptide a plausible candidate for testing. The algal polypeptide was shown to be a high-molecular-weight copolymer of argine and aspartic acid, and its synthesis was not inhibited by chloramphenicol (5, 6).To answer the above questions, we undertook experiments on the primary structure of the peptide and studied the effect of puromycin on the biosynthesis of the peptide.MATERIALS AND METHODS Materials. The histidine-rich polypeptide was isolated as previously described (2). Pepsin, trypsin, and chymotrypsin were purchased from Worthington; Nagarse was from En- 900), pH 6.5. The sample was applied at tUie middle of the strip. For preparative purposes, guide strips were cut and stained with ninhydrin-cadmium reagent (7) and peptides were eluted with 30% acetic acid.Amino-Acid Analysis. Peptides were hydrolyzed in 200Ml of 6 N HC1 containing 0.2% (w/v) phenol and 0.1% (v/v) mercaptoacetic acid in evacuated sealed tubes, at 1100 for 22 hr (8). Hydrolysates were analyzed with a modified amino-acid analyzer (9). Polyacrylamide Gel Electrophoresis. Electrophoresis was according to the method of Panyim and Chalkley (10).Incorporation of [3HlHistidine In Vitro. Uninucleate trophozoites of P. lophurae were removed from their host duck erythrocytes and cultured extracellularly under conditions described previously (11). To facilitate quantitative collection of parasites at the end of the incubation period, the plasma clot lining of the culture flask was omitted. To each...

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Studies on the Host—parasite Relationships of Untreated Infections With Plasmodium Lophurae in Ducks1

Cited by 16 publications

References 0 publications

Intracellular phagotrophy by malaria parasites: an electron microscope study of Plasmodium lophurae*

Intracellular phagotrophy by malaria parasites: an electron microscope study of Plasmodium lophurae*

Influence of Biotin Upon Susceptibility to Malaria

On primary structure and biosynthesis of histidine-rich polypeptide from malarial parasite Plasmodium lophurae.

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