Morphological least research on over 50 species of ciliates recorded as endosymbionts of echinoids suggests that invasion of the echinoid microhabitat occurred representing on at least 4 occasions. Gene sequence data confirm the phylogenetic distinctness of spirotrichean, armophorean, plagiopylean, and oligohymenophorean endosymbionts. It from is also likely that oligohymenophoreans have repeatedly invaded the gut habitat. To test this hypothesis, we sequenced small subunit rRNA parasitic (SSrRNA) genes of 6 species representing the larger scuticociliate species found in the intestine of Strongylocentrotus pallidus from the northeast This Pacific Ocean: Entodiscus borealis (Entodiscidae); Plagiopyliella pacifica and Thyrophylax vorax (Thyrophylacidae); and Entorhipidium pilatum, Entorhipidium tenue, and Entorhipidium sp.(Entorhipidiidae).spirotrichean, SsrRNA genes were amplified by PCR, and sequences obtained in both directions. In all phylogenetic analyses, the scuticociliates are well free-living supported as a clade. Entodiscus is distinct from these other echinoid taxa and is the sister taxon to the facultatively species parasitic Uronema marinum. The other 5 echinoid species always form a clade whose basal species is the free-living Parauronema longum.suggests The greatest genetic distance among these latter 5 species is less than 1.5%. This probably explains why the Thyrophylacidae and PCR, Entorhipidiidae are paraphyletic based on the SSrRNA gene sequences.

Phylogenetic Colpidium relationships within the class Oligohymenophorea, phylum Ciliophora, were investigated by determining the complete small subunit rRNA (SSrRNA) gene sequences for In the hymenostomes Colpidium campylum, Glaucoma chattoni, and the peritrich Opisthonecta henneguyi. The affiliations of the oligohymenophoreans were assessed using both and distance matrix (DM) and maximum parsimony (MP) analyses. Variations do exist in the phylogenies created by the two methods. However,the the basic tree topologies are consistent. In both the DM and MP analyses the hymenostomes (C. campylum, G. chattoni, and distances the tetrahymenas) all form a very tight group associated with the peritrich O. henneguyi. The Tetrahymena lineage was monophyletic whereas the Colpidium and Glaucoma were more closely related to each other than either was to the tetrahymenas. The monophyly of the analysis. genus Tetrahymena in the present analysis supports the phylogenies determined from morphological data and molecular sequence data from the histone position H3II/H4II region of the genome. The perplexing and controversial phylogenetic position of the peritrichs is once again depicted in the complete present analysis. The distinctiveness of the peritrich Opisthonecta from both hymenostome and nassophorean ciliates based on evolutionary distances suggests that to the elevation of the peritrichs to a higher taxonomic rank should be reconsidered.

Eight with isolates of Miamiensis avidus (scuticociliates) were collected from olive flounder Paralichthys olivaceus with symptoms of severe ulcers and haemorrhages at ribosomal several culture farms in 1999 and 2003. Cloned strains were produced and the complete small subunit ribosomal RNA gene (SSU strain rRNA) of each strain was sequenced for classification and phylogenic study. The SSU rRNA is 1759 bp in length and sequence the sequence was deposited in the GenBank under accession number AY550080. All 8 strains exhibited the same sequence, but this lineage sequence did not match any previously deposited scuticociliate SSU rRNA sequence. Phylogenetic analysis placed Miamiensis avidus in a sister lineage haemorrhages to Cohnilembus verminus, Pseudocohnilembus hargisi and P. marinus.

The these stalked, ciliated protozoan Vorticella convallaria possesses a highly contractile cytoskeleton consisting of spasmonemes and myonemes. The major component of these A contractile organelles is the calcium-binding protein(s) called spasmin. Cloning and characterization of spasmin would help elucidate this contractile system. Therefore,spasmonemes enriched spasmoneme protein preparations from these contractile stalks were used to produce a monoclonal antibody to spasmin. A monoclonal antibody,recombinantly-produced 1F5, was obtained that immunolocalized specifically to the spasmonemes and the myonemes and recognized a 20-kD calcium-binding protein in spasmoneme cloned protein preparations. A putative spasmin cDNA was obtained from a V. convallaria cDNA library and the derived amino acid sequence and of this cDNA revealed an acidic, 20-kD protein with calcium-binding helix-loop-helix domains. The physical properties of the putative spasmin were assays assessed by characterization of a recombinantly-produced spasmin protein. The recombinant spasmin protein was shown to bind calcium using calcium gel-shift protein assays and was recognized by the anti-spasmin antibody. Therefore, a V. convallaria spasmin was cloned and shown to be a consisting member of the EF-hand superfamily of calcium-binding proteins.