Simple Synthesis of Climacostol,a Defensive Secretion by the Ciliate Climacostomum virens

Climacostol {1,3-dihydroxy-5-[(Z)-2'-nonenyl]benzene,1}, a defensive secretion by the protozoan ciliate Climacostomum virens against predators, was synthesized in a 43% overall yield in three steps by starting from methyl 1,3-bis(tert-butyldimethylsilyloxy) phenylacetate (3).     

Microscopic investigation of three species of Diophrys (Ciliophora,Euplotida, Uronychiidae) from Japan,including Diophrys peculiaris nov. spec

Three species of Diophrys, D. peculiaris nov. spec., D. cf. scutum and D. oligothrix, isolated from the New Nagasaki Fishing Port, Nagasaki, Japan, were investigated using live observation and protargol impregnation. Diophrys peculiaris nov. spec. can be recognized by having two characteristic clusters of rod-like structures and two groups of dikinetids located on anterior dorsal portion of cell. Morphogenetic data show that this part of the life cycle basically proceeds as in congeners, except for the formation of dikinetids under the rod-like structures. In the opisthe, the origin of dikinetids under the rod-like structures is still unknown, but the old dikinetids under the rod-like structures may be retained by the proter. The Japanese population of Diophrys cf. scutum resembles other populations of D. scutum well except for moniliform macronuclear segments. Our populations of D. oligothrix correspond well with other populations in terms of general morphology and ciliary pattern, in particular the continuous dorsal kineties with loosely arranged cilia.     

Hyalophysa lynni n. sp. (Ciliophora,Apostomatida), a new pathogenic ciliate and causative agent of shrimp black gill in penaeid shrimp

The parasitic ciliate causing shrimp black gill (sBG) infections in penaeid shrimp has been identified. The sBG ciliate has a unique life cycle that includes an encysted divisional stage on the host’s gills. The ciliature of the encysted trophont stage has been determined and is quite similar to that of the closely related apostomes Hyalophysa bradburyae and H. chattoni. Hyalophysa bradburyae is a commensal ciliate associated with freshwater caridean shrimp and crayfish, while H. chattoni is a common commensal found on North American marine decapods. Based on 18S rRNA gene sequence comparisons, the sBG ciliate is more closely related to the marine species H. chattoni than to the freshwater species H. bradburyae. The unique life cycle, morphology, 18S rRNA gene sequence, hosts, location, and pathology of the sBG ciliate distinguish this organism as a new species, Hyalophysa lynni n. sp.     

Some but not All Tetrahymena Species Destroy Monolayer Cultures of Cells from a Wide Range of Tissues and Species

The activities of Tetrahymena corlissi, Tetrahymena thermophila, and Tetrahymena canadensis were studied in coculture with cell lines of insects, fish, amphibians, and mammals. These ciliates remained viable regardless of the animal cell line partner. All three species could engulf animal cells in suspension. However, if the animal cells were monolayer cultures, the monolayers were obliterated by T. corlissi and T. thermophila. Both fibroblast and epithelial monolayers were destroyed but the destruction of human cell monolayers was done more effectively by T. thermophila. By contrast, T. canadensis was unable to destroy any monolayer. At 4 °C T. thermophila and T. corlissi did not carryout phagocytosis and did not destroy monolayers, whereas T. canadensis was able to carryout phagocytosis but still could not destroy monolayers. Therefore, monolayer destruction appeared to require phagocytosis, but by itself this was insufficient. In addition, the ciliates expressed a unique swimming behavior. Tetrahymena corlissi and T. thermophila swam vigorously and repeatedly into the monolayer, which seemed to loosen or dislodge cells, whereas T. canadensis swam above the monolayer. Therefore, differences in swimming behavior might explain why T. corlissi has been reported to be a pathogen but T. canadensis has not.     

The Ability of Tetrahymena utriculariae (Ciliophora,Oligohymenophorea) to Colonize Traps of Different Species of Aquatic Carnivorous Utricularia

The host specificity of the recently described ciliate species Tetrahymena utriculariae was tested in a greenhouse growth experiment, which included 14 different species of aquatic Utricularia as potential host plants. We confirmed the high specificity of the interaction between U. reflexa and T. utriculariae, the former being the only tested host species able to maintain colonization for prolonged time periods. We conclude that this plant–microbe relationship is a unique and specialized form of digestive mutualism and the plant–microbe unit a suitable experimental system for future ecophysiological studies.     

腹毛目纤毛虫鬃棘尾虫纤毛器基部微管的荧光标记

腹毛目纤毛虫鬃棘尾虫的纤毛器微管骨架由口围带、波动膜、额腹横尾棘毛、左右缘棘毛和背触毛等纤毛器微管和纤毛器基部附属微管等组成,其中口围带基部含小膜托架、小膜后微管、小膜托架微管及小膜托架间的倒"V"形微管连接;波动膜基部形成微管骨架网;额腹横棘毛和左、右缘棘毛基部含前纵微管束、后纵微管束和横微管束,但不同位置的棘毛基部微管发达程度不一样;背触毛基部以纤毛基体为中心向前、后皮层发出前纵微管和后纵微管,形成背皮层微管网.     

Sequence and Properties of Cagein,a Coiled-Coil Scaffold Protein Linking Basal Bodies in the Polykinetids of the Ciliate Euplotes aediculatus

In the hypotrich ciliate Euplotes, many individual basal bodies are grouped together in tightly packed clusters, forming ventral polykinetids. These groups of basal bodies (which produce compound ciliary organelles such as cirri and oral membranelles) are cross-linked into ordered arrays by scaffold structures known as “basal-body cages.” The major protein comprising Euplotes cages has been previously identified and termed “cagein.” Screening a E. aediculatus cDNA expression library with anti-cagein antisera identified a DNA insert containing most of a putative cagein gene; standard PCR techniques were used to complete the sequence. Probes designed from this gene identified a macronuclear “nanochromosome” of ca. 1.5 kb in Southern blots against whole-cell DNA. The protein derived from this sequence (463 residues) is predicted to be hydrophilic and highly charged; however, the native cage structures are highly resistant to salt/detergent extraction. This insolubility could be explained by the coiled-coil regions predicted to extend over much of the length of the derived cagein polypeptide. One frameshift sequence is found within the gene, as well as a short intron. BLAST searches find many ciliates with evident homologues to cagein within their derived genomic sequences.     

刘家峡水库网箱养鱼场纤毛虫群落特征

2006年3月至2007年2月, 用活体观察法和直接计数法对刘家峡水库网箱养鱼场纤毛虫群落进行了研究.共鉴定到77种纤毛虫, 其中包括4个未定名种, 隶属于3纲11目34科43属.下毛目为优势类群, 前口目为次优势类群, 异毛目为偶见类群.善变膜袋虫、长圆膜袋虫、珍珠映毛虫、钩刺斜管虫和大口瞬目虫为春季群落优势种; 善变膜袋虫、颗粒膜袋虫和珍珠映毛虫为夏季群落优势种; 颗粒膜袋虫和善变膜袋虫为秋季群落优势种; 冬季无明显优势种.纤毛虫物种数的周年动态呈单峰型, 8、9月份物种数最多, 有52种, 3月份最少, 只有18种; 物种数的季节动态为: 夏季＞秋季＞春季＞冬季.纤毛虫丰度的周年动态呈三峰型, 高峰分别出现在4月、6月和9月份, 5月份采样前夕水库调水导致丰度骤降是造成三峰型的主要原因; 纤毛虫丰度的季节动态为: 夏季＞秋季＞春季＞冬季.纤毛虫物种多样性指数的周年动态为: 8月份最大, 3月份最小.相关性分析结果表明, 对网箱养鱼场纤毛虫物种数影响最大的因子是水温, 其次是透明度和pH值, 投放饲料量的影响最小; 对网箱养鱼场纤毛虫丰度影响最大的是投放饲料量, 其次是水温和pH值, 透明度的影响最小.