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21.
ZHENZHEN YI WEIBO SONG THORSTEN STOECK KHALED A. S. AL‐RASHEID ABDULAZIZ A. AL‐KHEDHAIRY JUN GONG HONGWEI MA ZIGUI CHEN 《Zoological Journal of the Linnean Society》2009,157(2):227-236
The morphologically unique ciliate Psammomitra has long been considered as a systematically uncertain stichotrich. This is mainly because of its highly specialized morphology and a lack of either detailed information concerning its ontogenesis, or molecular data. Based on the small subunit rRNA (SSrRNA) gene and alpha‐tubulin gene sequences, we re‐evaluated the phylogenetic position of Psammomitra retractilis using multiple algorithms. Phylogenetic trees inferred from the SSrRNA gene sequences representing a total of 53 spirotrichs demonstrated the closest relationship of Psammomitra was with Holosticha‐like taxa, with strong support, which clearly suggested that Psammomitra should be placed into the order Urostylida although it branched at a rather deep level, and is likely to be closely related to Holostichidae. With consideration to molecular evidence and morphological characters, Psammomitra should be a clearly outlined taxon at about the rank of family, i.e. Psammomitridae stat. nov. , within the order Urostylida. The improved diagnosis for this family is as follows: Urostylida possessing extremely contractile, elongated body which consists of three parts: head, trunk, and slender tail; midventral complex composed of midventral pairs only and restricted to about anterior 1/3 of ventral surface; frontal, frontoterminal, and transverse cirri present; one left and one right marginal rows which commence near proximal end of adoral zone and extend to near rear body end. 相似文献
22.
Carlos García-Estrada Inmaculada Vaca Ricardo V Ullán Marco A van den Berg Roel AL Bovenberg Juan Francisco Martín 《BMC microbiology》2009,9(1):104-15
Background
Penicillium chrysogenum converts isopenicillin N (IPN) into hydrophobic penicillins by means of the peroxisomal IPN acyltransferase (IAT), which is encoded by the penDE gene. In silico analysis of the P. chrysogenum genome revealed the presence of a gene, Pc13g09140, initially described as paralogue of the IAT-encoding penDE gene. We have termed this gene ial because it encodes a protein with high similarity to IAT (IAL for IAT-Like). We have conducted an investigation to characterize the ial gene and to determine the role of the IAL protein in the penicillin biosynthetic pathway. 相似文献23.
In this study, the relationship between the concentration of extra-heavy crude petroleum in a clayey material and the toxicity, field capacity, temperature, and growth of a tropical forage grass (Brachiara humidicola) was determined empirically. For this type of petroleum the acute toxicity (Microtox®) was slight (CE50 = 63200 - 76400 mg/kg) even at high hydrocarbon concentrations (29279 mg/kg). Nonetheless, serious impacts were encountered in terms of an increase in soil temperature (+ 1.3 °C), reduction in field capacity (-10.7%) and reduction in aerial biomass (-97%). The relationship between hydrocarbon concentration and biomass resulted in a typical dose-response curve (r = 0.99), where a concentration of 2626 mg/kg of hydrocarbons corresponds to a maintenance of 90% biomass. Furthermore, during the duration of this study (one year) the biodegradation was proportional to the pasture biomass production (r = 0.997) indicating a synergistic relationship between the petroleum biodegrading microorganisms in the rhizosphere and the pasture. 相似文献
24.
M. Yu. Dyakov O. V. Kamzolkina O. V. Shtaer N. A. Bis’ko N. L. Poedinok O. B. Mikhailova O. V. Tikhonova T. E. Tolstikhina B. F. Vasil’eva O. V. Efremenkova 《Microbiology》2011,80(2):274-285
Twenty-one strains belonging to 18 species of basidiomycetes from different ecological groups of fungi were isolated from
natural sources. Light and electron microscopy was used to determine the morphological properties of the cultures, which confirmed
their classification as basidiomycetes and facilitated their identification in monocultures. The capacity of the fungal strains
for biosynthesis of antibiotics was determined by one- or two-stage cultivation on seven nutrient media. It was established
that, under submerged cultivation, antimicrobial substances were formed by 13 strains (81.25%) of 12 fungal species (Armillaria sp., Coprinus comatus, Flammulina velutipes, Hypsizygus ulmarius, Lentinus tigrinus, Lycoperdon pyriforme, Macrolepiota procera,
Panellus serotinus, Pholiota aurivella, Pholiota lenta, Rhodocollybia maculate, and Sparassis crispa). The antibiotics formed were efficacious against bacterial test strains, including the methicillin-resistant strain Staphylococcus aureus (MRSA) and the strain Leuconostoc mesenteroides VKPM B-4177 that is resistant to the glycopeptide antibiotics. No antibiotic activity was revealed against fungal test cultures
(Aspergillus niger INA 00760 and Saccharomyces cerevisiae RIA 259). 相似文献
25.
Angela Karp Steve J.Hanley Sviatlana O.Trybush William Macalpine Ian Shield 《Acta Botanica Sinica》2011,(2)
Willows (Salix spp.) are a very diverse group of catkin-bearing trees and shrubs that are widely distributed across temperate regions of the globe.Some species respond well to being grown in short rotation coppice (SRC) cycles,which are much shorter than conventional forestry.Coppicing reinvigorates growth and the biomass rapidly accumulated can be used as a source of renewable carbon for bioenergy and biofuels.As SRC willows re-distribute nutrients during the perennial cycle they require only minimal nitro... 相似文献
26.
Mycotoxin Research - Six laboratories analyzed portions of the same aqueous acetonitrile extracts of three peanut butters for aflatoxin concentrations by an HPLC procedure (using immunoaffinity... 相似文献
27.
Oocysts of Eimeria saudiensis n. sp. (Apicomplexa: Eimeriidae) are described from the feces of the Arabian oryx, Oryx leucoryx , from the Riyadh Zoo, Saudi Arabia. The oocysts were ellipsoidal or slightly ovoid, 31.2 times 24.5 (24.3–36.5 times 20.0–27.6) μm with a bilayered wall about 1.7 μm thick. The micropyle was covered by a dome-shaped cap. The oocyst residuum was absent, but tiny polar granules were present. The sporocysts were elongate ovoid, 14.3 times 7.2 (11.5–18.5 times 6.0–9.0) μm, had a Stieda body, but lacked a substiedal body. The sporocyst residuum was present, composed of numerous small granules. The sporozoites were elongate club-shaped, and contained two prominent refractile bodies. 相似文献
28.
29.
Possible protective mechanisms exerted by metformin or metformin and vitamin E in isoproterenol‐induced cardiac injury
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30.
EARLY STARVATION1 specifically affects the phosphorylation action of starch‐related dikinases
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Irina Malinova Harendra Mahto Felix Brandt Shadha AL‐Rawi Hadeel Qasim Henrike Brust Mahdi Hejazi Joerg Fettke 《The Plant journal : for cell and molecular biology》2018,95(1):126-137
Starch phosphorylation by starch‐related dikinases glucan, water dikinase (GWD) and phosphoglucan, water dikinase (PWD) is a key step in starch degradation. Little information is known about the precise structure of the glucan substrate utilized by the dikinases and about the mechanisms by which these structures may be influenced. A 50‐kDa starch‐binding protein named EARLY STARVATION1 (ESV1) was analyzed regarding its impact on starch phosphorylation. In various in vitro assays, the influences of the recombinant protein ESV1 on the actions of GWD and PWD on the surfaces of native starch granules were analyzed. In addition, we included starches from various sources as well as truncated forms of GWD. ESV1 preferentially binds to highly ordered, α‐glucans, such as starch and crystalline maltodextrins. Furthermore, ESV1 specifically influences the action of GWD and PWD at the starch granule surface. Starch phosphorylation by GWD is decreased in the presence of ESV1, whereas the action of PWD increases in the presence of ESV1. The unique alterations observed in starch phosphorylation by the two dikinases are discussed in regard to altered glucan structures at the starch granule surface. 相似文献