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41.
Cortinarius sarcoflammeus is proposed as a new species belonging to subgenus Dermocybe, on the basis of its morphological, chemical and ecological characters. The strong red-orange colour of the context and stipe
base, large spores, sphagnicolous habitat and high dermorubin content are characteristic for the new species. Holotypes of
C. huronensis and C. huronensis var. olivaceus have been examined for comparison, and their differences discussed. Photographs and line drawings of C. sarcoflammeus are added.
Received February 13, 2001 Accepted March 23, 2001 相似文献
42.
A M Belles T J Montville B P Wasserman 《Journal of industrial microbiology & biotechnology》2000,24(1):71-74
Alcohol-extractable, hydrophobic zein proteins contaminate starch granule surfaces and can be removed by enzymatic digestion
with thermolysin. The goal of this research was to find practical alternatives to thermolysin that might be used during the
corn wet-milling process. All of the commercial thermostable alkaline proteases studied (SP 709, Neutrase, and Spezyme FAN)
removed the zein proteins from various types of cornstarch, as demonstrated by the lack of protein bands below 30 kDa under
the reducing conditions of SDS-PAGE gel. Each enzyme removed the zein proteins as effectively as thermolysin removed them.
However, the removal of the zein protein did not reduce the quantity of free fatty acids associated with the starch. Journal of Industrial Microbiology & Biotechnology (2000) 24, 71–74.
Received 27 May 1999/ Accepted in revised form 01 October 1999 相似文献
43.
We studied the hibernation behavior of the water frog Rana lessonae and its hybridogenetic associate R. esculenta in their natural habitat during three successive winters. Animals caught in pitfall traps at a fenced pond were individually
marked with PIT tags and some (n=36) were additionally equipped with radio transmitters. Of the animals caught, 85% left the fenced pond for hibernation.
More R. esculenta remained inside the fenced area compared to R. lessonae. R. lessonae emigrated earlier in autumn and came back later in spring than R. esculenta, but the distance to their hibernation sites did not differ. Both species left the fenced pond earlier in the year when ambient
temperatures were lower. All radio-tracked animals hibernated in woodland, 3–7 cm below the surface in soil, under moss, fallen
leaves or small branches. Soil temperatures at the actual hibernation sites were significantly higher than at randomly chosen
control sites. A surprising finding was that most frogs changed their hibernation sites during winter, and often more than
once. Movements were more frequent in the warmer first half of the winter than in the cooler second half, but some animals
were active even on days with mean temperatures below 1°C. These results show that both species do not spend the whole winter
torpid in one particular hibernation site but move around, especially at higher temperatures. Most of the animals lost weight
during the winter, and the weight loss was greater in females than in males and higher in warm than in cold winters. To what
extent weight loss and survival is influenced by the chosen hibernation sites and the amount of movement during winter, and
whether this contributes to the differences in species and sex ratios found in mixed populations, needs more investigation.
Received: 4 August 1999 / Accepted: 15 November 1999 相似文献
44.
Structure and Functions of Channel-Forming Peptides: Magainins,Cecropins, Melittin and Alamethicin 总被引:26,自引:0,他引:26
B. Bechinger 《The Journal of membrane biology》1997,156(3):197-211
45.
M. R. Duvall 《Plant Systematics and Evolution》2001,228(3-4):143-152
Critical morphological synapomorphies have not been found in support of the Acoranan hypothesis, the molecular phylogenetic
discovery that Acoranae are the basal monocots. The previously undetermined pattern of anther wall development in Acorus has been suggested to be one such character. Two main types of anther wall development have been recognized: 1) the “monocotyledonous”
type, which characterizes both monocots and dicots, and 2) the “dicotyledonous” type, which is almost exclusively found among
dicots. An anatomical study of anther wall development in Acorus was here undertaken using the electron microscope. Development of the anther wall in Acorus was found to be somewhat irregular or perhaps even intermediate between the two types although largely consistent with the
“monocotyledonous” type. The presumed significance of anther wall development and other critical morphological characters
to the Acoranan hypothesis in the absence of knowledge about the sister group to the monocots is evaluated.
Received August 28, 2000 Accepted February 19, 2001 相似文献
46.
Benjamin S. Johnson Lexie Chafin Daniela Farkas Jessica Adair Ajit Elhance Laszlo Farkas Joseph S. Bednash James D. Londino 《Molecular & cellular proteomics : MCP》2022,21(7):100256
Identifying protein–protein and other proximal interactions is central to dissecting signaling and regulatory processes in cells. BioID is a proximity-dependent biotinylation method that uses an “abortive” biotin ligase to detect proximal interactions in cells in a highly reproducible manner. Recent advancements in proximity-dependent biotinylation tools have improved efficiency and timing of labeling, allowing for measurement of interactions on a cellular timescale. However, issues of size, stability, and background labeling of these constructs persist. Here we modified the structure of BioID2, derived from Aquifex aeolicus BirA, to create a smaller, highly active, biotin ligase that we named MicroID2. Truncation of the C terrminus of BioID2 and addition of mutations to alleviate blockage of biotin/ATP binding at the active site of BioID2 resulted in a smaller and highly active construct with lower background labeling. Several additional point mutations improved the function of our modified MicroID2 construct compared with BioID2 and other biotin ligases, including TurboID and miniTurbo. MicroID2 is the smallest biotin ligase reported so far (180 amino acids [AAs] for MicroID2 versus 257 AAs for miniTurbo and 338 AAs for TurboID), yet it demonstrates only slightly less labeling activity than TurboID and outperforms miniTurbo. MicroID2 also had lower background labeling than TurboID. For experiments where precise temporal control of labeling is essential, we in addition developed a MicroID2 mutant, termed lbMicroID2 (low background MicroID2), that has lower labeling efficiency but significantly reduced biotin scavenging compared with BioID2. Finally, we demonstrate utility of MicroID2 in mass spectrometry experiments by localizing MicroID2 constructs to subcellular organelles and measuring proximal interactions. 相似文献
47.
《Molecular & cellular proteomics : MCP》2020,19(3):444-455
Highlights
- •Human spermatozoa possess cells of poor morphology that lack nuclear integrity.
- •These cells can be isolated by density separation.
- •Mass spectrometry reveals their nuclei contain excess protein.
- •TOP2A is a promising marker of this poor nuclear development.
48.
Hugues-Alexandre Blain Luis Gibert Carles Ferrndez-Caadell 《Comptes Rendus Palevol》2010,9(8):487-497
For the first time unequivocal fossil remains of a green toad (Bufo viridis s.l.) are described in the Iberian Peninsula. The fossils come from the Cueva Victoria site, a late Early Pleistocene (ca. 1.1–1.2 Ma) karstic filling in semi-arid southeastern Spain (Murcia region). By extension, other remains from two other Early Pleistocene Spanish localities, Barranco León D (ca. 1.3 Ma) and Almenara-Casablanca 3 (ca. 1.1 Ma), are cautiously attributed to the group B. viridis. The B. viridis group was previously reported with some uncertainty to the west of its current distribution area in Western Europe (Spain and France) in the Pliocene (Bufo cf. viridis) and less probably in the Early Miocene (Bufo aff. viridis). Since no osteological differences have been established between the recently described extant species of B. viridis s.l. (e.g. Bufo balearicus, Bufo siculus, Bufo boulengeri, B. viridis sensu stricto and Bufo variabilis) no precise palaeobiogeographical relationships can be drawn for the Spanish fossils. However, the occurrence of a third species of bufonid toad during the Pleistocene in the South of the Iberian Peninsula raises some interesting ecological questions in relation to the local disappearance of the green toad, which can be hypothetically linked to the intensification of the Pleistocene glacial/interglacial climate dynamic or to probable competition with another toad, Bufo calamita. 相似文献
49.
M. I. Jsselstijn J. Kaiser F. L. van Delft H. E. Schoemaker F. P. J. T. Rutjes 《Amino acids》2003,24(3):263-266
Summary. Novel synthetic procedures for the modification of non-proteinogenic acetylene-containing amino acids have been developed.
The functionalization either proceeds via zinc/copper-mediated introduction of alkyl substituents, or via tungsten-catalyzed
ring-closing alkyne metathesis reactions.
Received March 28, 2002 Accepted October 3, 2002 Published online December 18, 2002
Acknowledgements These investigations are supported (in part) by the Netherlands Research Council for Chemical Sciences (CW) with financial
aid from the Netherlands Technology Foundation (STW).
Authors' address: Floris P. J. T. Rutjes, Prof. Dr., Department of Organic Chemistry, University of Nijmegen, Toernooiveld 1, NL-6525 ED Nijmegen,
The Netherlands, E-mail: rutjes@sci.kun.nl
2, selected data: 1H NMR (300 MHz, CDCl3) δ 5.32 (d, J = 7.7 Hz, 1H), 4.44–4.40 (m, 1H), 3.76 (s, 3H), 2.75–2.73 (d, J = 5.0 Hz, 2H), 1.44 (s, 9H); 13C NMR (75 MHz, CDCl3) δ 171.0, 155.0, 80.3, 74.6, 52.6, 51.9, 41.7, 28.3, 24.0; mp = 55°C.
Typical procedure for 5: zinc dust (116 mg, 1.408 mmol) was weighed into a 20 mL flask, which was repeatedly evacuated (with heating using a heat
gun) and flushed with argon. Dry DMF (0.5 mL, distilled from CaH2) and 1,2-dibromoethane (9.2 μL, 0.106 mmol) were added and the flask was heated at 80°C for 40 min. The reaction mixture was allowed to cool to room temperature,
trimethylsilyl chloride (4 μL, 0.035 mmol) was added and the resulting mixture was stirred vigorously for a further 30 min under argon. Iodocyclohexane
(69 μl, 0.528 mmol) was added and stirred at room temperature for 3 h more after which stirring was ceased to settle the zinc.
CuCN (41 mg, 0.458 mmol) and LiCl (40 mg, 0.915 mmol) were heated to 150°C for 2 h and cooled to room temperature. Addition
of DMF (1 mL) formed a soluble CuCN·2LiCl complex within 5 min. After cooling the Cu-complex to −15°C, the organozinc reagent
was added dropwise followed by the bromoacetylene 2 (116 mg, 0.352 mmol). The mixture was allowed to stir overnight at room temperature. Water was added and the suspension was
extracted using heptane, washed with brine, dried (MgSO4) and concentrated. Purification using flash column chromatography (10% EtOAc in heptane) yielded 5 (100 mg, 81%) as a colorless oil. 5: IR ν 3355, 2929, 2852, 2359, 2337, 1749, 1717, 1498, 1447, 1365, 1251, 1181, 1060; 1H NMR (300 MHz, CDCl3) δ 5.28 (d, J = 7.7 Hz, 1H), 4.43–4.38 (m, 1H), 3.73 (s, 3H), 2.69–2.63 (m, 2H), 2.13 (m, 1H), 1.73–1.22 (m, 10H), 1.43 (s, 9H); 13C NMR (75 MHz, CDCl3) δ 171.4, 155.0, 88.1, 79.9, 73.8, 52.3, 32.7, 32.7, 28.8, 28.2, 25.8, 24.6, 23.1; HRMS (EI): calculated for C17H27NO4 309.1940, found 309.1937.
A solution of the tungsten catalyst (7 mg, 10 mol%) in C6H5Cl (2 mL) was treated with a solution of 14 (49.0 mg, 0.120 mmol) in C6H5Cl (5.0 mL) under an argon atmosphere and the resulting mixture was heated at 80°C for 3 h. Evaporation followed by flash
column chromatography (80% EtOAc in heptane) afforded 15 (21.0 mg, 50%; 64% after correction for starting material) and 14 (16 mg, 33%) as colorless oils. 15: [α]D =–14.6 (c = 1, CH2Cl2); IR ν 3313, 2931, 2865, 2249, 1744, 1667, 1520, 1366, 1170; 1H NMR (400 MHz, CDCl3) δ 7.14 (d, J = 8.7 Hz, 1H), 6.08 (d, J = 8.3 Hz, 1H), 4.78 (q, J = 6.8 Hz, 1H), 4.27 (q, J = 7.9 Hz, 1H), 3.73 (s, 3H), 2.17–2.15 (m, 4H), 2.07–1.96 (m, 2H), 1.79–1.52 (m, 4H), 1.45 (s, 9H), 0.89–0.83 (m, 2H); 13C NMR (100 MHz, CDCl3) δ 173.2, 171.8, 155.8, 80.4, 80.2, 79.3, 53.8, 52.5, 51.2, 32.8 (2×), 28.1, 24.6, 24.2, 18.3 (2×); HRMS (EI): calculated for
C18H28N2O5 相似文献
50.
《Fungal biology》2020,124(2):83-90
Latterly, the upsurge in use of antifungal drugs has brought about the emergence of several drug-resistance strains, making it skeptical to continue relying on current therapeutic regime. In the necessity of resistance-free antifungal agent, flavonoids presented possibilities of replacing existing drugs, displaying antifungal activity against pathogenic fungi. Among them, quercetin, one of the most representative flavonoids, exhibited antifungal activity against Candida albicans. To inspect the further understanding regarding quercetin, the antifungal mode of action of quercetin was investigated. In the initial step, the apoptosis was monitored after quercetin treatment. Moreover, intracellular levels of Mg2+ was assessed and was determined that Mg2+ increase occurred under the influence of quercetin. In addition, several features of mitochondrial dysfunction were monitored. Mitochondrial dysfunction triggers decrease in mitochondrial redox levels and leads to disruption in mitochondrial antioxidant system. Increased intracellular ROS and decreased intracellular redox levels were also displayed, indicating the occurrence of overall disruption in antioxidant systems. Sequentially, DNA fragmentation was observed and this DNA damage in turn induces apoptosis. In analyses, hexaamminecobalt(III) chloride (Cohex) was applied to inhibit Mg2+ transport between cytosol and mitochondria. Cohex attenuated the effects induced by quercetin, which demonstrates that the presence of Mg2+ is essential in quercetin-induced apoptosis. 相似文献