Taxonomic Clarification of A Well-Known Pathogenic Scuticociliate,Miamiensis avidus Thompson&Moewus,1964(Ciliophora,Scuticociliatia)

Miamiensis avidus Thompson & Moewus,1964,is a cosmopolitan and well-known marine pathogenic ciliated protist.However,the taxonomy of this species up to now has remained controversial,especially with respect to the validity of the morphologically similar species,Philasterides dicentrarchi,which was considered as a junior synonym of M.avidus.In this study,a population of M.avidus was collected from the skin of pharaoh cuttlefish(Sepia pharaonis) cultured near the East China Sea,Ningbo,China and its morphology and phylogeny were investigated in detail based on living characters,infraciliature,small subunit(SSU) r DNA and ITS1-5.8 S-ITS2 region sequences.In addition,the morphometrics of a previously reported free-living population,collected from the Bohai Sea,were rechecked and analyzed.We compared the present two isolates with all historic populations of M.avidus and P.dicentrarchi,and found that their morphological characters were either highly similar or exactly identical,indicating that they are the same morphospecies.However,the phylogenetic analyses based on SSU r DNA or ITS1-5.8 S-ITS2 region sequences revealed that most M.avidus and P.dicentrarchi populations formed one clade,and the two isolates of M.avidus from Weifang and American Type Culture Collection clustered in another clade,which indicated that there might be cryptic species in Miamiensis avidus.

最早被发现的细胞器——刺丝泡

单细胞的原生动物表膜下有一类特殊的细胞器——射出胞器,它们可在原生动物受刺激时快速发射内含的功能性物质,在原生动物的捕食、防御等生命活动中起着重要作用。刺丝泡是众多射出胞器类型中的一种,也是最早被发现的细胞器。本文主要从结构、细胞内起源、发射过程及其功能方面介绍刺丝泡在模式生物草履虫中的研究。

Ciliates in the Marsh Wetlands of Chongming Island: Taxonomy of Five Species and a Species List

To clarify the confusion surrounding species identification and state intraspecific variations, this research studied the morphological taxonomy of five species, Kentrophyllum cf. setigerum Petz et al., 1995; Zosterodasys shumerica Aliev, 1990; Frontonia tchibisovae Burkovsky, 1970; Neourostylopsis orientalis Chen et al., 2013; and Apoholosticha cf. sinica Fan et al., 2014, which were collected from Chongming Island's marsh wetlands. Kentrophyllum cf. setigerum possesses less somatic kineties than K. setigerum(19–26 right and 18–25 left kineties vs 35–40 right and 30 left kineties). Whether Z. shumerica is identical to Z. transversa Foissner et al., 1994, which was presented in a previous report, was negated. The improved diagnosis for the species is provided. Frontonia tchibisovae was confirmed to have three or four micronuclei, and the number of kinetosome rows in its peniculus 3 varied between China and Russia populations. The new population of N. orientalis bears cortical granules, which differs from the original population that has an arrangement of rows across the dorsal bristles. For A. cf. sinica, there are colorless cortical granules on the ventral side of the new population, whereas in the previously reported populations bright orange, spherical granules were clustered around dorsal cilia. Additionally, we sequenced the small-subunit(SSU) rRNA genes of K. cf. setigerum, N. orientalis, and A. cf. Sinica, and compared the new and reported populations. For the first time, we also provide a species list, including 33 ciliates collected from the wetlands based on living observation and silver staining.

3种微塑料与头孢拉定吸附作用的理论研究

微塑料(microplastics,MPs)和抗生素是海洋环境中的两类污染物,微塑料吸附水体中的抗生素后可作为其迁移的载体,对海洋环境及海洋生物产生更大的危害。不同微塑料对抗生素不仅相互吸附作用存在差异,而且吸附能力和机理均尚未取得深入明确的结论。本研究以聚乙烯(polyethylene,PE)、聚丙烯(polypropylene,PP)、聚酰胺(polyamide,PA)、紫外线老化聚酰胺(PA^(UV))以及紫外线和H_(2)O_(2)共同老化聚酰胺(PA^(UV)+H)为对象,通过密度泛函方法(DFT)的计算探究其对头孢拉定(cefradine,CE)的吸附能力和吸附稳定性。结果表明:CE在PE、PP、PA、PA^(UV)和PA^(UV+H)上的吸附属于物理吸附,其中PA、PA^(UV)和PA^(UV+H)的吸附稳定性强于PE和PP。静电作用在这3种PAs与CE之间的吸附机理方面发挥了重要的作用,使得它们对CE的吸附更加稳定。另外,根据热力学性质的计算结果表明,在T=273~311 K、P=1~1000 atm条件下所有MPs对CE的吸附都是一个自发的放热过程。