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1.
J. W. Paden 《Mycopathologia》1971,43(3-4):259-268
Three new species ofEupenicillium are described from soils from the western United States. They areE. idahoense sp. nov.,E. tularense sp. nov., andE. lasseni sp. nov. The conidial stages are new species ofPenicillium.
Zusammenfassung Drei neue Arten vonEupenicillium vom Erdboden der westlichen Vereinigten Staaten sind beschrieben worden. Diese sind:E. idahoense, sp. nov.,E. tularense, sp. nov. undE. lasseni sp. nov. Die Konidialformen sind neue Arten vonPenicillium.
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2.
3.
Although the genetic polymorphism of the alcohol-metabolizing enzymes was extensively studied at the molecular level by many investigators, the genetic polymorphism studies for ethanolmetabolizing enzymes in Mongolians are very rare. The present study was therefore performed to determine the genetic distribution of various forms of alcohol-metabolizing enzymes such as alcohol dehydrogenase 2 (ADH2, currently accepted nomenclature ADH1B), ADH3 (ADH1C), aldehyde dehydrogenase 2 (ALDH2) and cytochrome P4502E1 (CYP2E1) in 300 healthy Mongolian males. Genetic polymorphisms were determined by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) methods. The allele frequencies ofADH2 *1 andADH2 *2 were 0.24 and 0.76;ADH3 *1 andADH3 *2 were 0.92 and 0.08;ALDH2 *1 andALDH2 *2 were 0.96 and 0.04; andCYP2E1 *C andCYP2E1 *D were 0.15 and 0.85, respectively. Compared to the results reported by other investigators, the allele frequencies ofALDH2 *2 andCYP2E1 *C among Mongolian subjects were much lower than among East Asians (Korean, Japanese, and/or Han-Chinese), while those ofADH2 andADH3 were more similar. Interestingly, this study shows that the ineffectiveALDH2 gene (ALDH2*2 allele) among Mongolians is not as common as among East Asians.  相似文献   

4.
Scott A. Mori 《Brittonia》1981,33(3):466-472
Eschweilera tetrapetala Mori andE. alvimii Mori are described and compared withE. compressa (Vellozo) Miers, the only other species of this genus known to have four petals. It is concluded that this small group of species probably evolved from a common ancestor whose range was fragmented by climatic and vegetational changes in the Pleistocene. The distributions ofE. compressa andE. alvimii support the hypothesis that moist forest refuges existed around Rio de Janeiro and southern Bahia/northern Espírito Santo throughout the Pleistocene.  相似文献   

5.
The chromosome ofAzotobacter vinelandii was digested with the restriction endonucleasesSpeI (5’-ACTAGT),DraI (5’-TTTAAA) andAsel (5’-ATTAAT) and the products were separated by pulsed-field gel electrophoresis. The sum of the sizes of the restriction fragments comes to around 4.5 megabasepairs. Our earlier studies had revealed the presence of about 80 copies ofnifH, nifD, nifK andleuB genes in a log-phase cell ofA. vinelandii. To determine whether there are multiple identical chromosomes inA. vinelandii or one large chromosome with identical segments joined in tandem, we have subjected gamma-irradiated DNA ofA. vinelandii andEscherichia coli to pulsed-field gel electrophoresis. The results suggest thatA. vinelandii chromosomes contain multiple identical chromosomes of about the same size as that ofE. coli.  相似文献   

6.
Mutations in severalPolycomb (Pc) group genes cause maternal-effect or zygotic segmentation defects, suggesting thatPc group genes may regulate the segmentation genes ofDrosophila. We show that individuals doubly heterozygous for mutations inpolyhomeotic and six otherPc group genes show gap, pair rule, and segment polarity segmentation defects. We examined double heterozygous combinations ofPc group and segmentation mutations for enhancement of adult and embryonic segmentation defects.Posterior sex combs andpolyhomeotic interact withKrüppel 2 and enhance embryonic phenotypes ofhunchback andknirps, andpolyhomeotic enhanceseven-skipped. Surprisingly, flies carrying duplications ofextra sex combs (esc), that were heterozygous for mutations ofeven-skipped (eve), were extremely subvital. Embryos and surviving adults of this genotype showed strong segmentation defects in even-numbered segments. Antibody studies confirm that expression ofeve is suppressed by duplications ofesc. However,esc duplications have no effect on other gap or pair rule genes tested. To our knowledge, this is only the second triplo-abnormal phenotype associated withPc group genes. Duplications of nine otherPc group genes have no detectable effect oneve. Expression ofengrailed (en) was abnormal in the central nervous systems of mostPc group mutants. These results support a role forPc genes in regulation of some segmentation genes, and suggest thatesc may act differently from otherPc group genes.  相似文献   

7.
Artemisia absinthium is an aromatic and medicinal plant of ethnopharmacological interest and it has been widely studied. The use ofA. absinthium based on the collection of wild populations can result in variable compositions of the extracts and essential oils (EOs). The aim of this paper is the identification of the active components of the vapour pressure (VP) EO from a selected and cultivated A. absinthiumSpanish population (T2-11) against two parasitic protozoa with different metabolic pathways: Trypanosoma cruzi andTrichomonas vaginalis. VP showed activity on both parasites at the highest concentrations. The chromatographic fractionation of the VP T2-11 resulted in nine fractions (VLC1-9). The chemical composition of the fractions and the antiparasitic effects of fractions and their main compounds suggest that the activity of the VP is related with the presence oftrans-caryophyllene and dihydrochamazulene (main components of fractions VLC1 and VLC2 respectively). Additionally, the cytotoxicity of VP and fractions has been tested on several tumour and no tumour human cell lines. Fractions VLC1 and VLC2 were not cytotoxic against the nontumoural cell line HS5, suggesting selective antiparasitic activity for these two fractions. The VP and fractions inhibited the growth of human tumour cell lines in a dose-dependent manner.  相似文献   

8.
Serologically active polysaccharide, galactomannan, was isolated from whole cells ofH. capsulatum, H. duboisii, P. brasiliensis andB. dermatitidis, and their chemical structure and immunological properties were described.  相似文献   

9.
The present study examines the polysaccharide composition of the brown alga Eisenia bicyclis. The major polysaccharide of E. bicyclis is shown to be sodium alginate (15.8% of the dry defatted alga weight). The yields of laminaran and fucoidan were 1.4% and 1.3% of the dry defatted alga weight, respectively. The alga contains laminaran (1,3;1,6-β-D-glucan) that has a unique structure, a high content of 1,6-linked D-glucose residues (the ratio of 1,3: 1,6 linkage is 1.5: 1), and an unusually high molecular weight (19–27 kDa). The fucoidan fractions isolated from E. bicyclis are sulfated and acetylated heteropolysaccharides that differ in their sulfate content and monosaccharide composition.  相似文献   

10.
To study the mechanism of spontaneous and UV-induced illegitimate recombination, we examined the formation of theλbio specialized transducing phage inEscherichia coli. Because mostλbio transducing phages have double defects in thered andgam genes and have the capacity to form a plaque on anE. coli P2 lysogen (Spi? phenotype), we selectedλbio transducing phage by their Spi? phenotype, rather than using thebio marker. We determined sequences of recombination junctions ofλbio transducing phages isolated with or without UV irradiation and deduced sequences of parental recombination sites. The recombination sites were widely distributed onE. coli bio andλ DNAs, except for a hotspot which accounts for 57% of UV-inducedλbio transducing phages and 77% of spontaneously inducedλbio transducing phages. The hotspot sites onE. coli andλ DNAs shared a short homology of 9 bp. In addition, we detected direct repeat sequences of 8 by within and near both thebio andλ hotspots. ArecA mutation did not affect the frequency of the recombination at the hotspot, indicating that this recombination is not a variant ofrecA-dependent homologous recombination. We discuss a model in which the short homology as well as the direct repeats play essential roles in illegitimate recombination at the hotspot.  相似文献   

11.
John T. Mickel 《Brittonia》1993,45(3):213-218
The fern genusElaphoglossum is well represented in wet, mountainous regions of Latin America, from which many species have recently been described. Six more new species ofElaphoglossum are reported:E. bryogenes from Ecuador andE. caudulatum, E. diminutum, E. delasotae, E. lellingeri, E. subcordatum, andE. xiphiophorum from Colombia.  相似文献   

12.
Dynamics of the buried seeds and plant population of two dominant weeds, viz.,Emilia sonchifolia (Linn.) DC. andRichardsonia pilosa HBK were studied in the crop fields of Meghalaya, north-east India during radish and maize cropping and intervening fallow periods. The total buried seed population ofR. pilosa was always larger than that ofE. sonchifolia, but the germinable fraction was invariably greater in the latter. A major portion (39–41%) of the viable (germinable+dormant) seed population in both weeds was confined to the surface soil layer (0–5 cm). The viable seed population ofE. sonchifolia peaked during April, while that ofR. pilosa showed two peaks (during August and December). The survival pattern and half-lives of seedling cohorts showed, some differences in the two weed species, but both being summer annuals, their populations behaved in a similar manner by showing higher seedling recruitment (K) and survivorship (p) rates in the summer crop (maize) than in the winter crop (radish). However, the density of plants that could attain adulthood was significantly higher inE. sonchifolia thanR. pilosa which might have resulted in greater seed input of the former to the soil leading to its greater abundance in the crop fields.  相似文献   

13.
DNA base composition of species of the genusSaccharomyces   总被引:1,自引:0,他引:1  
DNA base compositions (GC content) ofSaccharomyces species are reported and discussed. Several amendments of the four groups given by van der Walt are suggested, viz. the transfer ofS. kluyveri to group 1, and ofS. eupagycus, S. cidri, S. montanus, S. microellipsodes andS. florentinus to group 2. The synonomy ofS. amurcae andS. cidri is suggested. The DNA base compositions revealed two possible pairs of sibling species:S. elegans andS. bailii, with a difference in GC content of 4.1%;S. dairensis andS. servazzii with a difference in GC content of ca. 3%.S. mrakii had a GC content of 47.3–48.5% the highest encountered in this genus and similar to that ofKluyveromyces thermotolerans.  相似文献   

14.
This study characterises the bacteria associated with a marine hatchery in Tunisian coastal marine waters. Presumptive vibrios (TCBS agar) and heterotrophic aerobic microflora (CFU) were studied at different stages within the hatchery: seawater, batches of algal cultures, rotifers andArtemia culture tanks. The bacterial strains were isolated on TCBS Agar plates and described using different bacteriological tests (standardised micromethods “API 20 E Strips”, exoenzymes production, growth at different temperatures, pH and salinity, vibriostatic agent O/129 and antibiotics susceptibility). Two dominant genera of bacteria were found (Vibrio andAeromonas) associated with some strains of thePseudomonadaceae family.Vibrio alginolyticus was the dominant bacteria (75% of total isolates) found in rotifers (Brachionus plicatilis) andArtemia cultures (Artemia salina). In larvae rearing tanks, an increase ofVibrionaceae was noted after larvae were fed withArtemia. Most of the studied bacteria used the skin mucus ofSparus aurata larvae as their sole source of carbon. All theV. alginolyticus strains were β-haemolytic, hydrolyse the DNA and were susceptible to several tested antibiotics.  相似文献   

15.
Sexual dimorphism was found in the number of teeth on the jaws ofGymnothorax richardsoni and in the shape of teeth ofEchidna nebulosa andE. polyzona. Males ofG. richardsoni have fewer teeth than females. Males of two species ofEchidna have sharper teeth than females.  相似文献   

16.
Loxosceles spider venom usually causes a typical dermonecrotic lesion in bitten patients, but it may also cause systemic effects that may be lethal. Gel filtration on Sephadex G-100 ofLoxosceles gaucho, L. laeta, orL. intermedia spider venoms resulted in three fractions (A, containing higher molecular mass components, B containing intermediate molecular mass components, and C with lower molecular mass components). The dermonecrotic and lethal activities were detected exclusively in fraction A of all three species. Analysis by SDS-PAGE showed that the major protein contained in fraction A has molecular weight approximately 35 kDa inL. gaucho andL. intermedia, but 32 kDa inL. laeta venom. These toxins were isolated from venoms ofL. gaucho, L. laeta, andL. intermedia by SDS-PAGE followed by blotting to PVDF membrane and sequencing. A database search showed a high level of identity between each toxin and a fragment of theL. reclusa (North American spider) toxin. A multiple sequence alignment of theLoxosceles toxins showed many common identical residues in their N-terminal sequences. Identities ranged from 50.0% (L. gaucho andL. reclusa) to 61.1% (L. intermedia andL. reclusa). The purified toxins were also submitted to capillary electrophoresis peptide mapping afterin situ partial hydrolysis of the blotted samples. The results obtained suggest thatL. intermedia protein is more similar toL. laeta toxin thanL. gaucho toxin and revealed a smaller homology betweenL. intermedia andL gaucho. Altogether these findings suggest that the toxins responsible for most important activities of venoms ofLoxosceles species have a molecular mass of 32–35 kDa and are probably homologous proteins.  相似文献   

17.
The present paper deals with cytotaxonomy ofChelidonium majus L. s. 1. taxa and their hybrids. Based on results of hybridization experiments, cytology and reproductive isolation, a new combination,Ch. asiaticum (Hara) Krahulcová, is proposed. The structure of the aggregate is as follows:Ch. majus L. subsp.Majus (2n=12, distributed in Europe),Ch. majus L. subsp.grandiflorum (DC.)Printz (2n=12, S. Siberia, China) andCh. asisaticum (2n=10, E. Asia). Karyotypes ofCh. m. subsp.grandiflorum andCh. asiaticum are compared in detail.  相似文献   

18.
19.
The seagrass and macroalgal vegetation of Gazi Bay (at approximately 50 km south of Mombasa) have been studied by means of 88 relevés along 7 transects. Correlation between the distribution of the seagrasses and some abiotic factors (particle size fractions, chemical composition of the substrate) is not well marked. Nevertheless a general zonation and succession of seagrasses could be established:
  1. A transition zone between the mangal and the seagrass beds is covered byBoodleopsis pusilla;
  2. the pioneer associationHalophila ovalis +Halodule wrightii forms low sandy bumps at the upper limit of the seagrass beds, but also occurs in the whole midlittoral where sandlayers have recently been accumulated (e.g. on coral platforms);
  3. the climax vegetation of the intertidal zone seems to beThalassia hemprichii which sometimes is associated withCymodocea rotundata andC. serrulata, certainly in deeper pools and close to low water mark;Halimeda opuntia,Gracilaria salicornia andG. corticata are also frequent in this vegetation type;
  4. from low water at neap tide downwards patches of monospecificEnhalus acoroides vegetation can also occur;
  5. from mean low water down to approximately ?1 m mixed meadows ofThalassia, C. serrulata, C rotundata andHalodule uninervis are well developed; the seaweedsHalimeda macrooloba andAvrainvillea obscura are also typical for this zone; locally patches ofSyringodium isoetifolium grow on small bumps andHalophila stipulacea grows as a pioneer on bare sand;
  6. from ?1 m downwards the whole lagoon is covered by homogeneous, monospecificThalassodendron ciliatum meadows, locally replaced byE. acoroides.
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20.
Among the ascomycete isolates from soil and armadillo dung collected in São Paulo State, Brazil, a new species ofEmericella, E. montenegroi and a new variety ofE. rugulosa, E. rugulosa var.Iazulina are described and illustrated.Emericella montenegroi differs from the other known species of the genus in having ascospores with an incompletely reticulate or ribbed ornamentation on the convex walls.Emericella rugulosa var.Iazulina differs from the type variety in having blue to violet color of ascospores. Isolations ofE. corrugata andE. foveolata are also reported as a South American record. A synoptic key to all accepted species of the genus is provided.  相似文献   

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