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1.
Abstract The present study focused on the bryoflora of watercourses of the Tiber River basin watercourses (Central Italy). A total of 20 bryophyte species, which included 14 mosses and 6 liverworts, were collected at 32 river stations. Most species were recorded at stations of the watercourses' upper sections, which have rocky substrate and where there is cool and well oxygenated running water, with low trophic load. Only few species, such as Leptodictyum riparium, Cinclidotus fontinaloides and Riccia fluitans, were also found at stations of the middle and lower sections, which are characterized by slow-flowing, turbid, warm and eutrophic waters. Some species are widely distributed, among which Fontinalis antipyretica ssp. antipyretica and Platyhypnidium riparioides, while others are very rare, such as Cinclidotus aquaticus, Dialytrichia mucronata and R. fluitans. Some of the collected species are new regional records (Hygroamblystegium fluviatile, D. mucronata), regional confirmations of rare taxa in Italy (C.aquaticus) or confirmations of old regional reports (Hygroamblystegium tenax, C. fontinaloides, Aneura pinguis). 相似文献
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Luigi Desole 《Plant biosystems》2013,147(1-3):71-77
Abstract MONTE LINAS, A NEW BRIGDE STATION IN THE SARDINIAN DISTRIBUTION OF SCILLA OBTUSIFOLIA POIR. — Two new phytocenosis of Scilla obtusifolia Poir. in Sardinia on Monte Linas have been described; their particular interest is that they connect the so far stations of this species in Sardinia. Monte Linas acts as a bridge between the southern sardinian stations and the northern ones, which have been already described by DESOLE (1959). 相似文献
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Giuseppe Giaccone 《Plant biosystems》2013,147(3):217-222
Abstract Phytobenthos from Eastern Mediterranean Sea. — The A. states the results of an exploration, by diving techniques, in the Eastern Mediterranean Sea, along 13 stations located in the midle-western and southern region of the Aegean Sea. Besides to the values of various ecology elements (saltness, brightness, nutrition salts), informations about reologic regime in the Aegean Sea are reported. It has been collected 175 floral entities, with the following per cent composition: Chlorophyceae 14,5%, Phoeophyceae 17,0%, Rhodophyceae 68,3%. Eastern Mediterranean Sea underwater flora presents in the explored stations a R/P index equal to 4, which characterizes it as a subtropical one. 相似文献
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M. Cesa G. Azzalini V. De Toffol M. Fontanive F. Fumagalli P. L. Nimis 《Plant biosystems》2013,147(1):173-180
Abstract Moss bags of the aquatic bryophyte Rhynchostegium riparioides (Hedw.) C.E.O. Jensen (=Platyhypnidium riparioides (Hedw.) Dixon) were transplanted into freshwaters of the Province of Belluno (NE Italy). This study was aimed at testing the bioaccumulation of trace elements in Pre-alpine Dolomitic streams, where this species does not grow naturally, and where analyses of water samples have never revealed trace element pollution. Mosses were collected after 13, 26 and 59 days of exposure. The concentrations of nine trace elements in the apical shoots were measured. Average concentrations reached in three control stations were adopted as background values, to calculate the contamination factor (CF). Transplants accumulated trace elements and discriminated between non- or scarcely contaminated waters (low CF) and polluted ones (high CF). Furthermore, two patterns of contamination were revealed by multivariate analysis: (I) metals (Cr, Cu, Ni) from galvanic industries, and (II) metals (Pb, Zn) from other industrial/domestic sources or mine sites. 相似文献
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Abstract Two new italian stations of Jonopsidium savianum (Caruel) Ball ex Arc. – The authors point out the presence of Jonopsidium savianum (Caruel) Ball ex Arc. in two stations in the mount la Pelosa (Central Apennines). These new stations are characterized by a different climate as regards of those already well-known of mount Calvi, mount Pelato and mount Carvoli in Tuscany. This italian endemism, till now limited to the western Tuscan, had very probably an area of distribution in Central Italy more videly extended than nowadays, but the climatic changes of the post-glacial period may have caused its reduction and the isolation of this species only in very little stations. 相似文献
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Manlio Chiappini 《Plant biosystems》2013,147(3-5):302-321
Abstract CHRYSANTHEMUM FLOSCULOSUM L. in Sardinia. — After a synthesis of wath pertains to already known the localities of Sardinia in which Chrysanthemum flosculosum L. occurs, several interesting new stations of the insular endemism are shown and described with ecological notes. The sardinian area of the species, which as at present hadn't yet been pointed out, is split in three principal fragments: a) the Southern zone with one submountain and two lower littoral stations; b) the Central zone with stations on the mountain group of Gennargentu (m. 700–900 a. t. s. l.); c) the N-Western zone with the certainly most conspicuous station on little elevated grounds (at the most m. 240 a. t. s. l.). Chrysanthemum flosculosum L. represents a relict of the old tertiary flora migrated from the submountain districts to coastal marshes and, belonging to the mesophilousigrophilous macchia of Oleo-Lentiscetum, occurs on unlike kind of moist soils, as calcareous or schistous; it dwells not on granitic rocks of the Island. 相似文献
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【背景】分枝杆菌LY-1因能够将天然植物甾醇代谢转化为重要甾体药物中间体,目前已成为工业上的优势生产菌株。高效的CRISPR/Cas9基因编辑技术是工业菌株代谢工程改造进行产量性状提升的关键。然而由于Cas9蛋白的高表达毒性问题且分枝杆菌中已公开报道的可用表达元件较少,极大地限制了Cas9蛋白在该菌株中的适度表达。【目的】筛选内源性表达元件,利用合适的表达元件启动Cas9蛋白的表达,降低其对菌株的毒性。【方法】依据文献和前期研究获得的分枝杆菌基因转录组水平数据,并结合启动子在线预测网站BDGP(https://www.fruitfly.org/seq_tools/promoter.html),筛选内源性表达元件。以增强型绿色荧光蛋白作为报告基因对表达元件的强度进行评估,并采用不同强度的表达元件启动Cas9蛋白的表达。【结果】获得了23个不同表达强度的表达元件,采用中等强度的表达元件及弱表达元件都降低了Cas9蛋白对分枝杆菌LY-1的毒性,实现了Cas9蛋白在该菌株中的适度表达。【结论】建立了分枝杆菌LY-1内源性表达元件库,为后续菌株中高效CRISPR/Cas9基因编辑技术的构建及关键... 相似文献
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《Plant Ecology & Diversity》2013,6(2-3):167-178
Background: The Wachau region along the river Danube in eastern Austria represents one of central Europe's hotspots of plant and animal species diversity. One of the typical landscape elements is vineyards, mostly established as linear elements on terraces along the slopes, with a characteristic and species-rich flora and fauna on terrace slopes lying between the cultivated terraces. Aims: We addressed the question of how the genetic variation of four plant species of open grassland vegetation types is distributed. We asked if levels and distribution of genetic diversity of the plant species Aster amellus, Gentianella aspera, Pulsatilla grandis, and Stachys recta were correlated with geographic distances along the terrace slopes. Methods: The dominant inherited molecular marker system random amplified polymorphic DNA (RAPD ) was used to estimate and compare the distribution of genetic diversity of the four selected species. Results: We found only low levels of correlation of the distribution of genetic variation with linear geographic patterns and obtained indirect evidence for high levels of gene flow between adjacent terrace slopes. Conclusions: We found that genetic diversity parameters of the four target species did not mirror the pattern of linear landscape elements, indicating that gene flow acts efficiently against the linear distribution of genetic variation. 相似文献
10.
Abstract A report about new or interesting plants in the Marche region. III. — The authors report about the occurrence in the Marche of 61 entities of specific or infraspecific rank, 22 of which are new or unpublished concerning the region, while the remaining 39 have been previously very little or imprecisely mentioned; as to the latter new localities and stations are shown or general information on the distribution over the Marche district has been supplied. Out of the first 22 entities, 18 (Fumaria muralis subsp. muralis, Cardamine flexuosa, Lunaria annua subsp. pachyrhiza, Colutea arborescens subsp. gallica, Astragalus monspessulanas subsp. illyricus, Cornus sanguinea subsp. australis, Galium verrucosum, Hedypnois rhagadioloides subsp. tubaeformis, Andryala tenuifolia, Sonchus asper subsp. glaucescens, Rheichardia picroides var. maritima, Podospermum canum, Scorzonera austriaca, S. hirsuta, Bidens frondosa, Guizotia abyssinica, Ambrosia elatior, A. trifida) are, as far as the authors know, quite new or unpublished concerning the Marche, while 4 (Rumex angiocarpus, Trifolium repens subsp. prostratum, Epilobium lanceolatum, Picris hieracioides subsp. spinulosa) are generally reported in Middle Italy or over the whole Italian territory by the general Floras, but till now have not been mentioned in works dealing with regional flora. 相似文献
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S. Sorbo A. Sinkkonen G. Aprile S. Strumia R. C. Cobianchi A. Leone 《Plant biosystems》2013,147(2):461-471
Abstract The lichen Pseudevernia furfuracea was exposed to environmental trace elements in the district of Acerra (province of Naples, southern Italy), one of the points forming Italy's “Triangle of Death”. P. furfuracea thalli were exposed in bags at different sites for 6 months, periodically collected and examined by transmission electron microscopy (TEM) to assess ultrastructural changes. An our earlier study demonstrated that these exposed lichens were strongly contaminated by trace elements (Sorbo S, Aprile G, Strumia S, Castaldo Cobianchi R, Leone A, et al. 2008. Trace element accumulation in P. furfuracea (L.) Zopf exposed in Italy's so-called Triangle of Death. Sci Total Environ 407: 647–654.). The algal cells were more affected than the fungal symbiont. Exposition at urban sites gave the most frequent changes. Four trace elements (Cd, Pb, Cu and Zn) were used to study the effects of ultrastructural trace element both in field and in vitro treatments. The lichen developed comparable ultrastructural changes when exposed to different trace elements and the changes were not specific to the treatment used (lichen bag exposition, in field and in vitro treatments). The in vitro treatment gave the highest frequency of damage at all time points. X-ray TEM microanalysis revealed trace elements inside the cell walls and the cytoplasmic vesicles of the lichens cultured with the trace elements; this localization is probably related to tolerance mechanisms. 相似文献
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G. Fornaciari 《Plant biosystems》2013,147(6):544-551
Abstract LINNAEA BOREALIS L. on the occidental slope of the Stelvio National Park. — Distribution of Linnaea borealis L. is here examined within territorial limits of the occidental slope of the National Park on the Stelvio, taking out and noticing, for many stations characteristics of association in which the plant has beenobserved. 相似文献
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Prof. Giuseppe Martinoli 《Plant biosystems》2013,147(4):557-575
Summary The occurance of Buxus balearica Willd. in Sardinia, already reported by Gennari (1864), and its indigenous state are confirmed by the present study. Its station and geographic distribution as well as the biocenosis in which this species takes part (Barbusi near Sulcis in S. Sardinia) are considered. The study of the Barbusi station, in comparison with others hitherto known, brings a general confirmation to Chiarugi's view concerning the mountainous origin of the mediterranea elements. Besides, it emphasizes the differences between the stations of B. balearica, an element of the mediterranea “macchia”, and those of B. sempervirens, an undergrowth element of mesophilous formations (deciduous woods), which only rarely belonges to more termophilous bioceneses. The author notes that both species belong to the same stage of Q. Ilex and that the altitude range in which the Q. Ilex stage is comprised is very wide in the different mediterranean regions. In addition, the author emphasizes that Buxus sempervirens occurs in Corsica and Atlas up to the upper limit of Quercetum Ilicis, together with species belonging to higher stages, whilst Buxus balearica belongs to the lower limit of Quercetum Ilicis in the underzone “Olea-Ceratonia”. The altimetric separation of these species is, therefore, obvious. Due to the compenetration of floras of mountainous origin during the phases of the Ice-period, the knowledge of the segregation epoch of these species from each other is made impossible. Buxus balearica occupies actually as eocene substratum and, therefore, shows edaphic exigences for soils of a certain age: a condition not occurring for Buxus sempervirens. Both Buxus species, together with other horeal-tertiary ones (all constituting actually, in the mediterranea countries, a special relict flora) belong to the Lauretum, in a historic sense (Chiarugi). 相似文献
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Christopher Jones Henrik Moller William Hamilton 《New Zealand journal of zoology.》2013,40(3):193-203
Abstract We review ways of individually identifying stoats (Mustela erminea) and similar small mammals from visits to bait stations or to monitoring devices in the field. Tracking devices are the cheapest and most practical method currently available of measuring the presence of a particular species, but there has been little research on the recognition of individuals. Elongation of tracking tunnels, or using sooty plates rather than ink to record prints, may improve detectability of individual markings. Recording visits to bait stations or tracking tunnels from DNA sequencing of hair or skin samples is likely to be prohibitively expensive for many monitoring programmes. Identification of stoats visiting bait stations or tracking tunnels using electronic devices has great potential, but these techniques are impracticably expensive because stoats move over such large areas that individual receivers and data loggers would be needed for each bait station. Chemical bait markers such as rhodamine B may be the most suitable method for identifying which animals have used a particular bait station. 相似文献
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T. Kuliński M. D. Bratek-Wiewiórowska A. Zielenkiewicz W. Zielenkiewicz 《Journal of biomolecular structure & dynamics》2013,31(4):495-507
Abstract The formation and stability of structural elements in two 5S rRNA molecules from wheat germ (WG) and lupin seeds (LS) as a function of Mg2+ concentration in solution was determined using the adiabatic differential scanning microcalorimetry (DSC). The experimentally determined thermodynamic parameters are compared with calculations using thermodynamic databases used for prediction of RNA structure. The 5S rRNA molecules which show minor differences in the nucleotide sequence display very different thermal unfolding profiles (DSC profiles). Numerical deconvolution of DSC profiles provided information about structural transformations that take place in both 5S rRNA molecules. A comparative analysis of DSC data and the theoretical thermodynamic models of the structure was used to establish a relationship between the constituting transitions found in the melting profiles and the unfolding of structural domains of the 5S rRNA and stability of its particular helical elements. Increased concentration of Mg2+ ions induces additional internal interactions stabilising 5S rRNA structures found at low Na+ concentrations. Observed conformational transitions suggest a structural model in which the extension of helical region E dominates over the postulated tertiary interaction between hairpin loops. We propose that helix E is stabilised by a sequence of non-standard pairings extending this helix by the formation of tetra loop e and an almost total reduction of loop d between helices E and D. Two hairpin structures in both 5S rRNA molecules: the extended C-C' and the extended E-E'-E” hairpins appear as the most stable elements of the structure. The cooperativity of the unfolding of helixes in these 5S rRNA molecules changes already at 2 mM Mg2+. 相似文献
17.
P. A.C.M. DE BOER R. F. JANSEN A. TER MAAT 《Invertebrate reproduction & development.》2013,57(1-3):167-176
Summary Male copulatory behavior of the hermaphroditic snail Lymnaea stagnalis is a complex one: the appetitive behavior consists of a number of elements which do not always appear in the same sequence and have variable durations. Backfills of the penis nerve revealed the neurons that send projections to the male copulatory apparatus. Immunocytochemical experiments have demonstrated that these neurons contain at least ten different messenger molecules. Based on in situ hybridization and chemical purification data, it is suspected that this number will probably be doubled. How the different neurons and the molecules they contain might be involved in generation of the different elements of male copulatory behavior is discussed. 相似文献
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为了解人工诱导海南龙血树(Dracaena cambodiana)所产血竭的化学成分,从其乙醇提取物中分离得到10个化合物,经波谱分析分别鉴定为socotrin-4?-ol(1)、homoisosocotrin-4?-ol(2)、(E)-3-(3,4-dihydroxybenzylidene)-7-hydroxy-chroman-4-one(3)、5-hydroxy-7-methoxy-3-(4?-hydroxybenzyl)-4-chromanone (4)、3-去氧苏木查耳酮(5)、苏木查耳酮(6)、7,4?-二羟基黄酮(7)、7,4?-二羟基-8-甲基黄酮(8)、丁香树脂醇(9)和邻苯二甲酸二(2-乙基己基)酯(10)。化合物1~10均为首次从人工诱导海南龙血树所产血竭中分离得到,其中化合物8为新天然产物,化合物3~6为首次从血竭中分离得到。化合物7和8对耐甲氧西林金黄色葡萄球菌具有生长抑制作用。 相似文献
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【目的】家蚕核型多角体病毒(Bombyx mori nucleopolyhedrovirus,BmNPV)隶属于杆状病毒,需要借助宿主细胞能量代谢进行自身增殖复制。家蚕ADP/ATP转运酶(Bombyx mori ADP/ATP translocase,BmANT)是线粒体转运蛋白,在BmNPV感染条件下和家蚕热休克蛋白60(heatshockprotein60,BmHSP60)具有直接的相互作用。因此,鉴定Bmant基因在BmNPV感染过程中的功能特征,有助于解析杆状病毒劫持宿主细胞因子促进自身增殖复制机制,完善杆状病毒和宿主相互作用网络。【方法】通过结构域预测BmANT蛋白的结构特征,荧光定量PCR分析Bmant基因在BmNPV感染后的变化特征;并过表达BmANT检测其对病毒DNA复制和病毒蛋白表达变化影响;进一步在转录水平分析Bmant和Bmhsp60基因的调控关系;最后通过流式细胞术等技术鉴定Bmant和Bmhsp60基因共同调控BmNPV增殖复制的机制。【结果】SMART软件预测显示BmANT包含3个线粒体载体结构域,BmNPV感染24 h后Bmant基因持续下调表达。过表达Bmant基因能够显著抑制BmNPV DNA的复制和VP39蛋白表达。荧光定量PCR分析显示Bmant和Bmhsp60基因具有相互拮抗作用,能够相互抑制转录。Bmant和Bmhsp60共同过表达分析显示,BmANT和BmHSP60共同作用BmNPV能够抑制病毒的增殖复制。【结论】结果表明,BmANT是一个线粒体载体蛋白,具有显著的抗病毒作用,能够下调Bmhsp60基因表达,并抑制BmNPV增殖复制。 相似文献
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在原核生物中,硒蛋白合成需要tRNA~(Sec) (SelC)与硒代半胱氨酸合成(Sec synthase, SelA)、硒代半胱氨酸特异性延伸因子(Sec-specificelongationfactor,SelB)之间相互作用。【目的】基于大肠杆菌掺硒机器,寻找tRNA~(Sec)骨架上关键核苷酸位点,为解决硒蛋白目前面临的掺硒效率较低、产量低的问题提供新思路。【方法】以大鼠细胞质型硫氧还蛋白还原酶(thioredoxinreductase1,TrxR1)为掺硒模式蛋白为定点突变tRNA~(Sec),转化至BL21 (DE3) gor-获得阳性重组菌株(携带pET-TRSter/pSUABC’),用于表达大鼠硒蛋白TrxR1,然后使用2¢,5¢ADP-Sepharose亲和层析和凝胶过滤两步法分离纯化TrxR1,最后利用经典硒依赖型DTNB还原反应测定TrxR1的酶活,分析关键核苷酸位点,评价掺硒效率。【结果】在存在SECIS元件的前提下,当SelA、SelB、tRNA~(Sec)共表达时,与野生型相比,携带突变型tRNA~(Sec)所共表达的TrxR1酶活力呈现不同程度的降低,其中E.colitRNA~(Sec)的G18、G19这两个位点的所有的TrxR1酶活远低于野生型(10%);然而,a26和b7的酶活相对较高。【结论】E. coli tRNA~(Sec)骨架上G18和G19位点对于维持tRNA稳定性和灵活性发挥了关键作用,位点突变引起tRNA结构变化会影响tRNA~(Sec)与掺硒元件的互作,因此有望通过改造tRNA核苷酸位点来提高硒蛋白的掺硒效率。 相似文献