Pretty Protozoa

Leptospironympha, a parasite of the wood-feeding cockroach...

Sat, 13 Apr 2013 08:11:15 -0700

Leptospironympha, a parasite of the wood-feeding cockroach Cryptocercus punctulatus.

Figures 10–15. SEM micrographs of Leptospironympha of Cryptocercus punctulatus showing symbiotic bacteria and surface details. 10. Symbiotic surface bacteria between flagellar bands of L. eupora (Scale bar=5 μm). 11, 12. Symbiotic surface bacteria on the posteriormost cell portion of L. wachula (Scale bars=3 μm and 2 μm respectively). 13. Granular particles on the flagella of L. eupora (Scale bar=1 μm). 14. Operculum of L. eupora, also showing flagella with a few granular particles (Scale bar=1 μm). 15. Anterior view of L. eupora showing the operculum and flagella with granular particles (Scale bar=2 μm).

from Carpenter KJ et al. 2010. Phylogenetic Position and Morphology of Spirotrichosomidae (Parabasalia): New Evidence from Leptospironympha of Cryptocercus punctulatus. Protist 161(1):122–132.

Life cycles and cell death of parasitic protozoa Trypanosoma...

Sat, 13 Apr 2013 07:55:00 -0700

Life cycles and cell death of parasitic protozoa Trypanosoma brucei, Leishmania spp., and Plasmodium falciparum.

from Proto WR et al. 2013. Cell death in parasitic protozoa: regulated or incidental? Nature Reviews Microbiol. 11:58-66.

Steinina ctenocephali, a parasite of the cat flea. from Alarcón...

Sat, 13 Apr 2013 07:44:00 -0700

Steinina ctenocephali, a parasite of the cat flea.

from Alarcón ME et al. 2011. Life Cycle and Morphology of Steinina ctenocephali (Ross 1909) comb. nov. (Eugregarinorida: Actinocephalidae), a Gregarine of Ctenocephalides felis (Siphonaptera: Pulicidae) in Taiwan. Zool. Studies 50(6): 763-772.

Six examples of protozoa (phagotrophic eukaryotes) that act as...

Thu, 11 Apr 2013 08:55:00 -0700

Six examples of protozoa (phagotrophic eukaryotes) that act as models. (a) Tetrahymena, a ciliate that has a versatile model role; image from the Open Access source. (b) The ciliates Paramecium and Didinium are used to evaluate predator–prey dynamics among other roles; image kindly provided by K. Hausmann. (c) Oxyrrhis is a marine flagellate that is emerging as model for a range of topics; image by D. Patterson and provided courtesy of microscope.mbl.edu. (d) Trypanosoma is a blood parasite that provides a source of mitochondria among other attributes; image rights obtained from Eye of Science. (e) Dictyostelium is a soil amoeba that is possibly the most important medical-model protozoon; image kindly provided by R.L. Blanton. (f) Monosiga is a choanoflagellate that is emerging as a model because of its phylogenetic affinity to metazoa; image kindly provided by the King Laboratory, UC Berkeley.

from Montagnes D. et al. 2012. The rise of model protozoa. Trends in Microbiol. 20(4):184-191.

Dileptus eating Tetrahymena (via)

Wed, 27 Feb 2013 14:15:00 -0800

Dileptus eating Tetrahymena (via)

Taxa present: 1. – Lobatula lobatula (Walker and Jacob); 2. –...

Wed, 27 Feb 2013 13:56:00 -0800

Taxa present: 1. – Lobatula lobatula (Walker and Jacob); 2. – Elphidium macellum (Fichtel and Moll); 3. – Elphidium excavatum (Terquem); 4. – Elphidium advenum (Cushman); 5. – Elphidium complanatum (D’Orbigny); 6. – Elphidium crispum (Linné); 7. – Rosalina globularis D’Orbigny; 8. – Nonion commune (D’Orbigny); 9. – Aubignyna perlucida (Heron-Allen and Earland); 10. – Haynesina germanica (Ehrenberg); 11. – Ammonia beccarii tepida (Cushman); 12. – Ammonia beccarii beccarii (Linné); 13. – Asterigerinata mamilla (Williamson); 14. – Turrispirillina sp.; 15. – Spirillina vivipara Ehrenberg; 16. – Trichohyalus aguayoi (Bermúdez). Umbilical view; 17. – Trichohyalus aguayoi (Bermúdez). Spiral view; 18. – Trochammina inflata (Montagu); 19. – Miliolinella eburnea (D’Orbigny); 20. – Quinqueloculina vulgaris D’Orbigny; 21. – Cornuspira involvens (Reuss); 22. – Miliolinella circularis (Bornemann).

from Blázqueza AM and J Userab. 2010. Palaeoenvironments and Quaternary foraminifera in the Elx coastal lagoon (Alicante, Spain). Quaternary Inter 222(1-2):68-90.

natureofnature: Petalotricha ampulla

Wed, 27 Feb 2013 05:15:03 -0800

natureofnature:

Petalotricha ampulla

ucsdhealthsciences: Hair and there Ciliated protozoa, like...

Thu, 21 Feb 2013 02:33:14 -0800

ucsdhealthsciences:

Hair and there

Ciliated protozoa, like these captured by Dylan Burnette of the National Institute of Child Health and Human Development using a confocal microscope (magnified 1,700X), are a diverse group of complex, single-celled organisms characterized by superficial hair-like organelles that they undulate to move themselves along. (Other motile protists have tails or false feet.)

Protozoa are abundant and common everywhere, found in ponds, lakes, rivers, oceans, soils and inside the human body. In the last case, that can be bad news since some species are parasitical and cause disease. Malaria, giardiasis, Leishmaniasis and dysentery are all examples of diseases involving protozoa, often transmitted to humans by the bite of a parasite-carrying insect.

Ciliates are frequently used to study basic mechanisms in evolution because they replicate both asexually and through sexual reproduction.

Asexual reproduction occurs by binary fission: The micronucleus undergoes mitosis and the macronucleus elongates and splits in half. The cell then divides in two. Both new cells have a copy of the micronucleus and macronucleus.

In sexual reproduction, genetic material is exchanged, called conjugation, between two organisms of different mating types. (Mating types is akin to gender but, in the case of ciliates, the number of mating types exceeds two.) Conjugation occurs when food is rare. Two cells form a bridge between their cytoplasms, their micronuclei undergo meiosis, macronuclei disappear and the haploid micronuclei are exchanged over the bridge. The cells then separate, form new macronuclei from their micronuclei, and divide to create four new cells.

Pretty complicated for a critter measuring less than two millimeters (the thickness of a nickel) in length.

Saccinobaculus sp. and Barbulanympha sp. (via) The oxymonad...

Tue, 05 Feb 2013 11:20:11 -0800

Saccinobaculus sp. and Barbulanympha sp. (via)

The oxymonad protist Saccinobaculus (foreground, at about 12 microns in diameter) orbiting the much larger parabasalid protist Barbulanympha (background, at about 100 microns in diameter), which is covered in a dense monolayer of rod-shaped symbiotic bacteria. From the hindgut of the wood-feeding roach Cryptocercus. Images by Kevin J. Carpenter. (More)

Dinoflagellates (via) Dr Paul Hargreaves and Faye Darling call...

Tue, 05 Feb 2013 10:40:03 -0800

Dinoflagellates (via)

Dr Paul Hargreaves and Faye Darling call this electron microscopic image of dinoflagellates ‘MiroMira2’, but we think it looks like a couple of muffins. (More)

Ceratochoris horrida (via)

Mon, 04 Feb 2013 11:20:16 -0800

Ceratochoris horrida (via)

Stentor sp. (via)

Mon, 04 Feb 2013 10:40:09 -0800

Stentor sp. (via)

A gregarine (via) Credit: James Marden. The parasite that causes...

Sun, 03 Feb 2013 11:00:30 -0800

A gregarine (via)

Credit: James Marden. The parasite that causes metabolic disorders in dragonflies, as it appears under an electron microscope at 100-micron scale. Known as gregarines, the parasite belongs to Apicomplexa, a group of microorganisms including protozoa that cause diseases like malaria and cryptosporidiosis. (More)

Frontonia mengi (via) (via) from Fan et al. 2011. Two novel...

Sat, 02 Feb 2013 11:00:10 -0800

Frontonia mengi (via) (via)

from Fan et al. 2011. Two novel marine Frontonia species, Frontonia mengi spec. nov. and Frontonia magna spec. nov. (Protozoa; Ciliophora), with notes on their phylogeny based on small-subunit rRNA gene sequence data. Int. J. Syst. Evol. Microbiol. 61(6):1476-1486.

natureofnature: Confocal fluorescence microscopy of mating...

Fri, 01 Feb 2013 11:00:05 -0800

natureofnature:

Confocal fluorescence microscopy of mating pairs of Tetrahymena thermophila labeled with antiserum to tubulin (blue), TCBP-25 (red), and sytox nuclear stain (green).

Euplotidium rosati and Euplotidium arenarium (via) Figure 4-7....

Thu, 31 Jan 2013 11:00:21 -0800

Euplotidium rosati and Euplotidium arenarium (via)

Figure 4-7. Scanning electron micrographs of Euplotidium rosati n. sp. (Fig. 4–6) and Euplotidium arenarium (Fig. 7). 4. Ventral view from the right side, where asterisks indicate frontoventral cirri. 5. Ventral view from the left side to evidence the lack of the left marginal cirrus. 6. Dorsal view. 7. Ventral view of Euplotidium arenarium. This specimen probably lost epixenosomes due to prolonged lab cultivation of the cells (see text). Asterisks indicate frontoventral cirri. DK, dorsal kineties; E, epixenosomes; LMC, left marginal cirrus; PP, peristomial plate; TC, transverse cirri. Bars = 10 μm. (More)

from Modeo et al. 2013. Morphological, ultrastructural, and molecular characterization of Euplotidium rosati n. sp. (Ciliophora, Euplotida) from Guam. J. Eukaryot. Biol. 60(1):25-36.

biocanvas: Two protozoan parasites, Trypanosoma brucei, are...

Thu, 31 Jan 2013 04:03:29 -0800

biocanvas:

Two protozoan parasites, Trypanosoma brucei, are shown infecting the liver of a mouse. T. brucei is the causative agent of African sleeping sickness in humans.

Image by Gilles Vanwalleghem, Daniel Monteyne, Etienne Pays, and David Pérez-Morga, Université Libre de Bruxelles.

nprglobalhealth: The Twisted Life Of Toxoplasma Gondii T....

Tue, 29 Jan 2013 01:57:09 -0800

nprglobalhealth:

The Twisted Life Of Toxoplasma Gondii

T. gondii has a split personality. Most people who pick up the ~~bacteria~~ protozoan from raw beef or pork show no symptoms at all. But others, can get pretty sick.

T. gondii also has a reputation for making cats crazy.

Here we can see the movement of the parasite filmed under a microscopy. The beautiful patterns show three types of motion:twirling, circular and helical.

Image by James M.McCoy/PlosPathogens

rhamphotheca: Stentor: What and Where Although most protozoans...

Mon, 28 Jan 2013 11:00:25 -0800

rhamphotheca:

Stentor: What and Where

Although most protozoans are microscopic, the Stentor is the exception to this rule and can be up to 2mm long! It is therefore larger than many of the multi-cellular organisms found in freshwater such as rotifers and water-fleas, and has been known to eat the smaller members of these groups. Stentor are usually present in most freshwater ponds.

Take a few pieces of the stem of any floating plant (eg. Potamogeton), which has spear-shaped leaves. Place the stems in some water in a shallow dish and allow a few minutes for the water to settle. Examine the stems with a 10x hand lens - any Stentor present on the stem will be visible as long trumpet-shaped organisms. Stentor may also be swimming freely, when they become more oval in shape with a narrowing at their posterior.

Autumn (the Fall) is a good time of year to find Stentor because leaves falling into a pond increase the bacteria population feeding on the decaying vegetation. This leads in turn to an increase in the population of protozoa such as Stentor which feed on the bacteria. Colonies of Stentor often occur, in which the lower parts of the animals are covered with a mucilaginous substance which they secrete…

(read more: Microscopy UK) (image: Proyecto Agua)

scientificillustration: The Dinoflagellata: the Dinophysoidae...

Mon, 28 Jan 2013 08:27:40 -0800

scientificillustration:

The Dinoflagellata: the Dinophysoidae by Charles Atwood Kofoid and Tage Skogsberg