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71.
NELSON R. COOLEY JAMES M. KELTNER JERROLD FORESTER 《The Journal of eukaryotic microbiology》1973,20(3):443-445
SYNOPSIS. Effects of 2 polychlorinated biphenyls, Aroclor 1248 and 1260, on axenic Tetrahymena pyriformis strain W were investigated and compared with published data on Aroclor 1254. Aroclors 1248 and 1260 at 1 mg/liter in the presence of 0.1% (v/v) polyethylene glycol 200 reduced significantly (P < 0.005) growth rates and 96-hr populations of T. pyriformis grown at 26 C. Both toxicants were ~ 0.001 as toxic as Aroclor 1254. Ciliates were exposed for 7 days to concentrated Aroclors 1248 40X, 1254 60X, and 1260 79X over initial concentrations in the media. Accumulation of Aroclors increased with increased chlorination. It is suggested that if levels in the environment reached those used in these studies, the chief ecologic effect of Aroclor 1254 would be reduction of availability of the ciliates as food and as nutrient regenerators, but with Aroclors 1248 and 1260, this effect would be secondary to accumulation of the toxicants by the ciliates. Accumulation of polychlorinated biphenyls by ciliates would permit the toxicants to enter aquatic food chains. Thus the compounds could exert toxic effects at higher trophic levels. 相似文献
72.
DONALD M. SPOON CHARLES O. FEISE II REBECCA SUE YOUN 《The Journal of eukaryotic microbiology》1977,24(3):471-474
SYNOPSIS The water-soluble, viscoelastic resin Polyox® (WSR 301), a poly(ethylene oxide) of high molecular weight (4 million) is introduced as a new slowing agent for protozoa. Generally, as the kinetic viscosity of the resin increased from 0.25% to 1% (w/v), the swimming velocity of Euglena gracilis, Didinium nasutum, Paramecium aurelia, Blepharisma undulans , and Prorodon platyodon decreased. The 1.0% solution had the highest viscosity and decreased velocity more effectively than 1.0% methyl cellulose and Protoslo® solutions. The Polyox solutions differed from those of methyl cellulose and Protoslo by having, in addition to viscous drag, an elastic recoil that pulled the protozoa backwards when their swimming efforts stopped. The toxicity of these slowing agents was determined using 10 P. aurelia /test slide preparation. Paramecium numbers decreased in 1.0% methyl cellulose and Protoslo to nearly zero by 24 hr; in Polyox, not only were most of these ciliates alive after 24 hr, but many survived for 96 hr and divisions occurred in 0.25% and 0.50% solutions. 相似文献
73.
The protozoans attached to the submerged roots of reed (Phragmites australis) in some small waters in Holland were studied during one year. Reed was chosen because it is a very common natural substrate
for epiphytically living animals. Marked changes in species abundance and overall population density are reported. Most important
quantitatively were the ciliates, especially peritrichs, on which emphasis is laid. Vorticella campanula Ehrenberg, 1831 is found to be the dominant species in spring and summer, other vorticellas being also very numerous. Suctorian
populations seem to change strongly within weeks without apparent reason. Small attached flagellates were also common. No
stalked Heliozoa or medium-sized flagellates were found. The generalisation of the results and comparisons with the literature
are discussed.
Zoological Laboratory, University of Amsterdam 相似文献
74.
利用活体观察和蛋白银染色技术对采自广东大亚湾沿岸水体的7个南海新纪录种:紧缩全列虫Holosticha diademata(Rees,1883)Kahl,1932、缩颈半腹柱虫Hemigastrostyla enigmatica(Dragesco & Dragesco-Kernéis,1986)Song&Wilbert,1997、念珠腹棘虫Gastrocirrhus monilifer(Ozaki & Yagiu,1942)Curds & Wu,1983、四核舍太虫Certesia quadrinudeata Fabre-Domergue,1885、斯特后尾柱虫Metaurostylopsis struederkypkeae Shao et al.,2008、盐尖毛虫Oxytricha saltans(Cohn,1866)Kahl,1932、小心毛虫Caryotricha minuta(Xu et al.,2008)Miao et al.,2009等腹毛类纤毛虫进行了形态学再研究,补充了有关活体形态学、纤毛图式以及性状变异等分类学新信息.结果显示,该7种的南海种群与我国北方海域种群之间存在不同程度的形态学差异. 相似文献
75.
利用非淹没培养皿法、活体观察法和蛋白银染色法,对采自甘肃临夏县和会宁县农田土壤的4种腹毛类纤毛虫,即柠檬管膜虫(Cyrtohymena citrina)、背触毛拟腹柱虫(Gastrostylides dorsicirratus)、沙栖蠕形尖毛虫(Vermioxytricha arenicola)和半残毛虫属一种(Hemisincirra sp.)进行了研究。结果表明,柠檬管膜虫、背触毛拟腹柱虫和沙栖蠕形尖毛虫为中国纤毛虫分布新记录种。半残毛虫属一种因缺失相关分类学、细胞发生学和分子学信息,此处暂作为未定名种处理。文中对4种纤毛虫的形态学特征进行了详细描述和讨论。 相似文献
76.
Fareeda Tasneem Farah R. Shakoori Muhammad Ilyas Naveed Shahzad Alexey Potekhin Abdul R. Shakoori 《Journal of cellular biochemistry》2020,121(8-9):3837-3853
Among ciliates, Paramecium has become a privileged model for the study of “species problem” particularly in the case of the “Paramecium aurelia complex” that has been intensely investigated. Despite extensive studies, the taxonomy of Paramecium is still challenging. The major problem is an uneven sampling of Paramecium with relatively few representatives of each species. To investigate species from the less discovered region (Pakistan), 10 isolates of Paramecium species including a standing-alone FT8 strain previously isolated by some of us were subjected to molecular characterization. Fragments of 18S recombinant DNA (rDNA), ITS1-5.8S-ITS2-5′LSU rDNA, cytochrome c oxidase subunit II, and hsp70 genes were used as molecular markers for phylogenetic analysis of particular isolates. The nucleotide sequences of polymerase chain reaction products of all markers were compared with the available sequences of relevant markers of other Paramecium species from GenBank. Phylogenetic trees based on all molecular markers showed that all the nine strains had a very close relationship with Paramecium primaurelia except for the FT8 strain. FT8 consistently showed its unique position in comparison to all other species in the phylogenetic trees. Available sequences of internal transcribed spacer 1 (ITS1) and ITS2 and some other ciliate sequences from GenBank were used for the construction of secondary models. Two highly conserved helices supported by compensatory base changes among all ciliates of ITS2 secondary structures were found similar to other eukaryotes. Therefore, the most conserved 120 to 180 base pairs regions were identified for their comparative studies. We found that out of the three helices in ITS1 structure, helix B was more conserved in Paramecium species. Despite various substitutions in the primary sequence, it was observed that secondary structures of ITS1 and ITS2 could be helpful in interpreting the phylogenetic relationships both at species as well as at generic level. 相似文献
77.
Resting cyst wall glycoproteins isolated from two colpodid ciliates are glycine-rich proteins 总被引:3,自引:0,他引:3
Two glycoproteins bands isolated from the cyst wall protein pattern of two colpodid ciliates, Colpoda inflata (gp46CI) and Colpoda cucullus (gp46CC) were analysed for their amino acid composition. Both glycoproteins are very rich in glycine and have a relatively high hydrophobicity, containing additionally many leucine and alanine residues. Their high degree of similarity is both quantitative and qualitative. Compared with just two previously published reports, their amino acid compositions are similar to those found in the hydrolysed cyst wall total proteins from the ciliates C. steinii and Paraurostyla spp. The amino acid composition corroborates that they are indeed glycoproteins, because asparagine, an amino acid residue suitable for the attachment to N-acetylglucosamine by its amide group (N-glycan), is abundant in both proteins. We discuss our data in relation to other glycine-rich proteins and a comparison with amino acid composition protein databases is carried out. 相似文献
78.
Entodiniomorph ciliates, belonging to the family Cycloposthiidae, are described from the stomach contents of Hippopotamus amphibius. Monoposthium acanthum gen. n., sp. n., with typical cycloposthiid structure, differs from other genera in having only 1 caudalium. Parentodinium gen. n., represented by P. africanum sp. n. and P. ostrea sp. n., although superficially resembling Entodinium, is considered to be a relatively unspecialized cycloposthiid. 相似文献
79.
Soil samples taken from the Valley of Flowers, a component of the Nanda Devi Biosphere Reserve in the Himalayan regions of
India showed the presence of twenty two free living species of ciliates. There is a preponderance of species which exhibit
oral ciliature and ontogenesis in the Gonostomum pattern. Of the four species of the genus Gonostomum, three viz., G affine, G gonostomoida and G kuehnelti are similar to described species; Gonostomum singhii is new. The two species of genus Paragonostomum viz., P minuta and P ghangriai are new. The three new species are described in the present paper. All these species show prominent hypertrophied ciliary
structures. Their paroral membranes reveal characteristic differences with respect to their position, number of constituent
cilia and the distance between adjacent cilia. It is proposed that such species specific features of the paroral membrane
have a bearing in exercising different food organism preferences as they co-exist at many sites. This single factor has possibly
played an important role in species diversification of this group of hypotrichs in this isolated habitat. 相似文献
80.
大型纤毛虫总RNA的提取方法 总被引:7,自引:0,他引:7
以冠突伪尾柱虫为材料,建立了一种适合于富含RNase和多糖的大型纤毛虫总RNA的提取方法。该方法采用异硫氰酸弧和β-巯基乙醇联合快速变性,酚、氯仿和异戊醇抽提,同时在变性剂存在的条件下两次选择性地沉淀RNA,从而有效地去除了DNA、蛋白质和多糖。所得RNA样品经电泳、紫外分光光度法检测和RT-PCR分析,证实为完整、均一且无基因组污染的总RNA.这为构建冠突伪尾柱虫有小核系与无小核系之间的削减文库、筛选两细胞系差异表达的基因奠定了基础。 相似文献