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71.
Yan-Hui Wang Hao-Yang Wu Dávid Rédei Qiang Xie Yan Chen Ping-Ping Chen Zhuo-Er Dong Kai Dang Jakob Damgaard Pavel Štys Yan-Zhuo Wu Jiu-Yang Luo Xiao-Ya Sun Viktor Hartung Stefan M. Kuechler Yang Liu Hua-Xi Liu Wen-Jun Bu 《Cladistics : the international journal of the Willi Hennig Society》2019,35(1):42-66
The phylogeny of true bugs (Hemiptera: Heteroptera), one of the most diverse insect groups in terms of morphology and ecology, has been the focus of attention for decades with respect to several deep nodes between the suborders of Hemiptera and the infraorders of Heteroptera. Here, we assembled a phylogenomic data set of 53 taxa and 3102 orthologous genes to investigate the phylogeny of Hemiptera–Heteroptera, and both concatenation and coalescent methods were used. A binode-control approach for data filtering was introduced to reduce the incongruence between different genes, which can improve the performance of phylogenetic reconstruction. Both hypotheses (Coleorrhyncha + Heteroptera) and (Coleorrhyncha + Auchenorrhyncha) received support from various analyses, in which the former is more consistent with the morphological evidence. Based on a divergence time estimation performed on genes with a strong phylogenetic signal, the origin of true bugs was dated to 290–268 Ma in the Permian, the time in Earth's history with the highest concentration of atmospheric oxygen. During this time interval, at least 1007 apomorphic amino acids were retained in the common ancestor of the extant true bugs. These molecular apomorphies are located in 553 orthologous genes, which suggests the common ancestor of the extant true bugs may have experienced large-scale evolution at the genome level. 相似文献
72.
Jiří Zahradník Jaroslav Nunvar Hana Pařízková Lucie Kolářová Andrea Palyzová Helena Marešová Michal Grulich Eva Kyslíková Pavel Kyslík 《Systematic and applied microbiology》2018,41(3):184-190
Two non-pathogenic strains R89-1 and R90T isolated from poppy seed (Papaver somniferum L.) wastes were phenotypically and genotypically characterized. Multilocus sequence analysis (MLSA) was conducted with six genes (atpD, glnA, gyrB, recA, rpoB, 16S rRNA). The strains represented a new species which clustered with Agrobacterium rubi NBRC 13261T and Agrobacterium skierniewicense Ch11T type strains. MLSA was further accompanied by whole-genome phylogeny, in silico DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) analyses for both strains. ANI and dDDH values were deep below the species delineation threshold. Phenotypic features of the novel strains unequivocally allowed their differentiation from all other Agrobacterium species. Unlike other agrobacteria, the strains were salt sensitive and were able to biotransform morphine alkaloids. The dominant cellular fatty acids are 18:1 w7c, 16:0 and 12:0 aldehyde/16:1 iso I/14:0 3OH summed in feature 2 and the major respiratory quinine is Q-10 (87%). The DNA G + C content is 56 mol%. Microbial community analysis indicated probable association with P. somniferum plant material. Altogether, these characteristics showed that strains R90T and R89-1 represent a new species of the genus Agrobacterium which we propose to name Agrobacterium bohemicum. The type strain of A. bohemicum is R90T (=CCM 8736T = DSM 104667T). 相似文献
73.
74.
A. Kocková-Kratochvílová J. Šandula A. Vojtková M. Pokorná V. Stuchlík 《Folia microbiologica》1967,12(4):327-344
The properties of 53 fermentation type II strains of the genusCandida Berkhout were studied. The strains in question were originally identified asCandida tropicalis (Castellani) Berkhout,Candida pelliculosa Redaelli,Candida robusta Diddens et Lodder,Candida intermedia (Cif. et Ashf.) Langeron et Guerra,Candida langeroni Dietrichson,Candida obtusa (Dietrichson) v. Uden et Carmo Sousa and as various intermediate forms between these and other similar species. The classification
criteria were extended by a number of very important characteristics, such as the degree of utilization of raffinose, the
assimilation of lysine, xylose, cellobiose, maltotriose, maltotetraose and arabinose, virulence for mice, nutrient requirements,
serological properties, etc. Actual classification was based on the numerical method of a similarity count. On the basis of
this extension of the classification criteria, the characteristics of the speciesCandida tropicalis (Castellani) Berkhout andCandida pelliculosa Redaelli were defined in greater detail.Candida intermedia, evaluated on the basis of previously employed characteristics (lactose utilization, non-assimilation of KNO3) does not appear to be a separate species, but a collection of different border-line forms of other species of this group.Candida robusta Diddens et Lodder is regarded as a member of the genusSaccharomyces, notCandida. The varietiesCandida tropicalis var.lambica andCandida pelliculosa var.cylindrica likewise do not seem to belong to the species concerned and will have to be studied in greater detail from the genetic aspect,
in relation to other membrane-forming types ofCandida.
The authors' extension of the classification criteria considerably reduced intraspecific variability, particularly in the
speciesCandida tropicalis (Castellani) Berkhout, and led to greater accuracy in the practical diagnosis of this species, which is frequent in clinical
material. 相似文献
75.
76.
Large-scale separation of magnetic bioaffinity adsorbents 总被引:1,自引:0,他引:1
Flat magnetic separator was used to separate magnetic bioaffinity adsorbents from litre volumes of suspensions. Both magnetic cross-linked erythrocytes and magnetic chitosan were efficiently separated; at least 95% adsorbent recovery was achieved at maximum flow rate (1680 ml min–1). Using this system low amounts of trypsin were concentrated from large sample volumes using magnetic erythrocytes as affinity adsorbent. 相似文献
77.
Ivo Šafařík Pavel Mucha Jiří Pechoč Jaroslav Stoklasa Mirka Šafaříková 《Biotechnology letters》2001,23(11):851-855
A Davis tube (a matrix-free, flow-through magnetic separator used mainly in mineral processing) has been tested for separation of magnetic affinity biopolymer adsorbents from larger volumes of suspensions. Both magnetic chitosan and magnetic cross-linked erythrocytes could be efficiently separated from litre volumes of suspensions. Up to 90% adsorbent recovery was achieved under optimised separation conditions. 相似文献
78.
79.
The current incidence ofEscherichia coli strains in healthy humans capable of producing the inhibitory exoproducts, such as temperate bacteriophages, corpuscular
or HMW (high-molar mass) and proteinaceous or LMW (low-molar mass) colicins and siderophores was determined. Fifty-threeE. coli strains were collected from the colons of 53 healthy human volunteers in Brno (Czechia) and tested for spontaneous and induced
production of inhibitory exoproducts in a cross-test against each other. Of the strains tested, 37.7% produced bacteriophages,
41.5% produced from one to several LMW colicins, 11.3% formed HMW colicins and 15.1% (eight strains) produced exocellular
siderophores different from enterochelin. Of these, seven strains formed aerobactin and one strain formed an untyped siderophore.E. coli strains differ greatly in the incidence of colicinogeny and lysogeny from its closest systemic relatives in the genusEscherichia and therefore should not be regarded as a model bacterium in this respect.
This work was supported by grants from theGrant Agency of the Czech Republic (310/01/0013 and 310/03/1091) and by the institutional support of theMinistry of Education, Youth and Sports of the Czech Republic (MŠM 002 162 2415). 相似文献
80.
M. Šlosárek 《Folia microbiologica》1977,22(4):262-268
It was the aim of the present communication to find a simple test for a reliable discrimination ofMycobacterium bovis BCG fromMycobacterium tuberculosis. A total of 26 BCG strains, out of them 10 Czechoslovak strains (2 lyophilized cultures of BCG of different batch, 6 strains
isolated from abscesses of children after BCG-vaccination and 2 strains from fatal cases after BCG-vaccination) and 16 strains
obtained from foreign laboratories, were used. Of the tested characteristics a combination of 3 tests, sensitivity to 1 μg
of 2-thiophene carbonylhydrazide (TCH), activity of 3 acylamidases (urease, nicotinamidase and pyrazinamidase) and a quantitative
nitrate test, was found to be most advantageous. The Czechoslovak strains ofMycobacterium bovis BCG were fully sensitive to TCH, of the 3 acylamidases mentioned above only urease was positive and nitrate was reduced only
little or not at all. On the other hand, strains ofMycobacterium tuberculosis were always resistant to TCH, had positive urease, nicotinamidase and pyrazinamidase and reduced nitrate very intensively. 相似文献