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1.
Gliding motility, ultrastructure and nutrition of two newly isolated filamentous sulfate-reducing bacteria, strains 5ac10 and 4be13, were investigated. The filaments were always attached to surfaces. Growth was supported by addition of insoluble aluminium phosphate or agar as substrata for gliding movement. Electron microscopy of ultrathin sections revealed cell walls characteristic of Gramnegative bacteria; the undulated structure of the outer membrane may pertain to the translocation mechanism. Intracytoplasmic membranes were present. Acetate, higher fatty acids, succinate or fumarate served as electron donors and carbon sources. Strain 5ac10 grew also with lactate, but not with benzoate that was used only by strain 4be13. Strain 5ac10 was able to grow slowly on H2 plus CO2 or formate in the presence of sulfate without additional organic carbon source. The capacity of complete oxidation was shown by stoichiometric measurements with acetate plus sulfate. Both strains contained b- and c-type cytochromes. Desulfoviridin was detected only in strain 5ac10. The two filamentous gliding sulfate reducers are described as new species of a new genus, Desulfonema limicola and Desulfonema magnum. 相似文献
2.
本文记述瘤忙属1新种--药山瘤虻Hybomitra yaoshanensis sp.nov.,模式标本保存在北京军事医学科学院。 相似文献
3.
This work treats species of the genus Microsternus Lewis, 1887 from Asia and North America. A new genus is described: Neosternus (type species Microsternus higonius Lewis, 1887). A new species is described: Microsternus pengzhongi. A new synonym is provided: Microsternus tricolor taiwanicus Nakane (=Microsternus tricolor Lewis). Three species previously placed in Microsternus Lewis, 1887 are transferred to Neosternus resulting in the following three new combinations: Neosternus higonius (Lewis, 1887), Neosternus taiwanus (Chûjô, 1976), and Neosternus hisamatsui (Nakane, 1981). 相似文献
4.
5.
目的:了解泰山沙参属植物资源现状,测定其根中脂肪、蛋白质及多糖的含量,为合理开发利用泰山沙参属植物资源提供依据。方法:采用野外实地调查法进行资源考察;分别用索氏提取法、考马斯亮蓝法和苯酚-硫酸法测定脂肪、蛋白质和多糖的含量。结果:采集的100余份标本,经鉴定为沙参属植物狭叶沙参[Adenophora gmeli-nii(Spreng)Fisch.]、石沙参(Adenophora polyantha Nakai)、杏叶沙参(Adenophora stricta Mig.)及细叶沙参(Adeno-phora paniculata Nannf.)。泰山沙参属植物狭叶沙参、石沙参、杏叶沙参和细叶沙参脂肪含量分别为2.14%~7.34%,4.27%~7.72%1,.54%~2.51%和4.98%。蛋白质含量分别为0.60~2.10 mg/g0,.80~1.89 mg/g,0.83~0.89 mg/g和1.05 mg/g,多糖含量分别为20.58%~63.21%2,7.74%~65.14%,43.14%~48.47%和45.60%。结论:泰山野生沙参属植物资源丰富,品种多、分布广、蕴藏量大,多糖含量较高,具有较大的开发前景。 相似文献
6.
许多研究表明,物种与高级分类阶元在数量上密切相关,这种关系在地区物种数量预测中具有很高的应用价值。应用中国不同地理类型(保护区、行政区和动物地理亚区)的鸟类物种名录,研究物种与科属的数量相关关系和频次分布规律,结果表明(1)物种与高级分类阶元在数量上有着极显著相关关系(P<0.01),其中物种—属的相关关系要显著于物种—科,且在对数、乘幂、指数和线数4种模型中,用乘幂模型拟合最好;(2)物种在科属间的频次分布具有规律性(P<0.05),随着物种数/科属的增加,频次迅速减少,在4种模型中,乘幂模型拟合最好,属的规律性较科显著。根据以上结果,物种与科属间的数量强相关关系与物种数量在科属间有规律的频次分布有关。 相似文献
7.
Yagi H Yasukawa N Yu SY Guo CT Takahashi N Takahashi T Bukawa W Suzuki T Khoo KH Suzuki Y Kato K 《Carbohydrate research》2008,343(8):1373-1377
Edible bird’s nest (EBN) is the nest made from the saliva of Collocalia swift. Recently, we have found that EBN extract could strongly inhibit infection of influenza viruses in a host-range-independent manner [Guo, C. T.; Takahashi, T.; Bukawa, W.; Takahashi, N.; Yagi, H.; Kato, K.; Hidari, K. I.; Miyamoto, D.; Suzuki, T.; Suzuki, Y. Antiviral Res. 2006, 70, 140–146]. Although this antiviral activity might be attributed to O- or N-glycoconjugates, no N-glycan structures have so far been described for EBN. Here, we report the N-glycosylation profile of EBN, in which a tri-antennary N-glycan bearing the 2,3-N-acetylneuraminic acid residues is displayed as a major component. We suggest that the sialylated high-antennary N-glycans of EBN contribute to the inhibition of influenza viral infection. 相似文献
8.
在横断山区鸟类考察过程中,发现采自四川宝兴县硗碛和雅江县八角楼的两号小鴞属标本与原记录的种类有显著差异,经研究认为是横斑腹小鴞(Athene brama)的一新亚种,命名为: 横斑腹小鴞 新亚种—杂斑腹小鴞Athene brama poikila Subsp.nov. 正模标本 雄性成鸟(采集号6079),1964年12月6日,采自四川省宝兴县的硗碛,海拔高度2,200米。标本保存在四川农业大学。 相似文献
9.
B. Desplanque P. Boudry K. Broomberg P. Saumitou-Laprade J. Cuguen H. Van Dijk 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(8):1194-1201
Beets belonging to the species Beta vulgaris L. can be found in crop, wild and weedy forms, all of which are interfertile. We studied the intra-specific genetic relationships
of about 300 individuals from 54 populations of various French geographic origins using nuclear molecular markers (five single-copy
RFLP loci and one microsatellite locus). The patterns of diversity were congruent for both types of markers. Genetic diversity
in wild beets appeared to be high, both in term of allele number and observed heterozygosity, whereas the narrowness of the
cultivated-beet gene pool was confirmed. Genetic distances between all forms showed that weed beets in northern France are
intermediates between sugar beet and inland wild beets in south-western France. This analysis allowed us to infer the paternal
origin of weed beets and furthermore, is in agreement with a previous study which focused on their maternal origin: weed beet
infesting sugar-beet fields originated from accidental and recurrent hybridization between cultivated lines and ruderal inland
wild beets during the production of commercial seeds in south-western France. Inland wild beets are genetically close to Mediterranean
coastal wild beets, but differ from other coastal forms (from Biscay, Brittany and northern France). The study of gene flow
in the beet complex contributes to the risk assessment of transgenic beets.
Received: 8 June 1998 / Accepted: 8 October 1998 相似文献
10.
新疆种子植物属的区系地理成分分析 总被引:23,自引:0,他引:23
对新疆种子植物区系733属的地理成分进行了分析。结果表明,新疆种子植物区系地理成分多样,以温带成分和古地中海成分占优势,前者占总属数的57%,后者占32.6%;热带成分只占6.7%,华夏成分占3.8%。这表明新疆种子植物区系特征与本地区所处的气候带、地理位置及其地史变迁是一致的。在古地中海遗迹上发生的本土成分在本植物区系组成中起重要作用,本植物区系是安加拉区系的一部分。 相似文献