卵黄萤荧光素再生酶基因的克隆与序列分析

目的 克隆和分析荧光素再生酶基因(LRE).方法 通过GeneBank中已知的荧光素再生酶基因保守区段设计引物,利用5'RACE(rapid-amplification of cDNA ends)和3'RACE技术克隆了来自云南省两双版纳州的卵黄萤(Luciola ovalis)荧光素再生酶基因cDNA和全基因序列.通过GeneBank、National Center for Bioteclmology Information和ProDom at the ExPASy Server软件和数据库进行序列分析.结果 卵黄萤荧光素再牛酶的cDNA序列和基因序列存在2个不同碱基位点,但是它们编码的荧光素再生酶是相同的.卵黄萤荧光素再生酶基因全长(从起始密码子到终止密码子)为1131 bp,包含5个外显子4个内含子,其cDNA 序列为1008 bp,包含924bp的荧光素酶基因开放阅读框和84 bp的3'UTR序列.卵黄萤荧光素酶基因的开放阅读框编码1个307个氨基酸的蛋白质.它与北美萤火虫(Photinus pyralis)荧光素再生酶在碱基序列和氨基酸序列上分别有61.8%和53.3%的相似性.结论 成功地克隆了荧光素再生酶的cDNA和基因序列,为其在基因工程中的应用奠定了基础.

中国桥弯藻科(硅藻门)的新记录植物

本文报道了采自新疆维吾尔自治区的桥弯藻科(硅藻门)中国新记录植物11种3变种,分别为Amphora mexi-canavar.major(Cleve)A.Cleve,Amphora twenteanaKrammer,Encyonema cespitosumK櫣tzing,Encyonema silesiacumvar.ventriformisKrammer,Cymbopleura albanicaKrammer et Miho,Cymbopleura apiculataKrammer,Cymbopleur

Temporal and Spatial Distributions of Rotifers in Xiangxi Bay of the Three Gorges Reservoir, China

From July 2003 to June 2005, investigations of rotifer temporal and spatial distributions were carried out in a bay of the Three Gorges Reservoir, Xiangxi Bay, which is the downstream segment of the Xiangxi River and the nearest bay to the Three Gorges Reservoir dam in Hubei Province, China. Thirteen sampling sites were selected. The results revealed a high species diversity, with 76 species, and 14 dominant species; i.e., Polyarthra vulgaris, Keratella cochlearis, Keratella valga, Synchaeta tremula, Synchaeta stylata, Trichocerca lophoessa, Trichocerca pusilla, Brachionus angularis, Brachionus calyciflorus, Brachionus forficula forficula, Ascomorpha ovalis, Conochilus unicornis, Ploesoma truncatum and Anuraeopsis fissa. After the first year of the reservoir impoundment, the rotifer community was dominated by ten species; one year later it was dominated by eight species. The community in 2003/2004 was dissimilar to that in 2004/2005, which resulted from the succession of the dominant species. The rotifer community exhibited a patchy distribution, with significant heterogeneity observed along the longitudinal axis. All rotifer communities could be divided into three groups, corresponding to the riverine, the transition and the lacustrine zone, respectively.

Cymbellaceae and Gomphonemataceae (Bacillariophyta) from the Hengduan Mountains region (southwestern China)

We present a species list of the Gomphonemataceae and Cymbellaceae occurring in the Hengduan Mountains re-ion. These two families were found to be presented in the area by 117 species, varieties and forms belonging to four genera (Amphora, Cymbella, Didymosphenia and Gomphonema). Size, striae density, habitat and distribution in China are given for each taxon. The common taxa were Cymbella aequalis var. piscicultis. C. affinis, C. cesatii, C. cistula var. gibbosa, C. delicatula. C. gracilis, C. hustedtii, C. minuta f. latens, C. minita var. silesiaca, C. naviculiformis, C. parva. C. turgidida, Gomphonema acuminatum var. acuminatum, G. gracile, G. intricatum, G. olivaceum. G. parvulum and G. truncatum var. capitatum. Some morphological features of Cymbella cistula var. capitata, Cymbella sinica var. miyiensis, Gomphonema hedinii and G. kaznakowii were found to differ from previously published descriptions. Taxa typical of high latitude climates encountered during the present study were Cymbella affinis, C. alpina, C. cistula var. cistida, C. delicatula. C. naviculiformis. Didymosphenia geminata, Gomphonema acuminatum var. pusillum, G. constrictum var. capitatum f. turgidum, G. kaznakowii, G. olivaceum, G. subtile var. subtile, G. tergestinum and G. ventricosum.

中国两种萤火虫荧光素酶基因的分子克隆表达及其序列分析

本文通过5’-RACE和3’-RACE方法克隆了西双版纳地区的卵黄萤Luciola ovalis和端黑萤Luciola terminalis两种荧光素酶基因。两个荧光素酶基因被连接到pET-15b载体上并在BL21(DE3)菌株中表达。L. ovalis荧光素酶基因的开放阅读框有1635个碱基，编码一个544个氨基酸的蛋白。L. terminalis荧光素酶基因有一个1647bp的开放阅读框，编码一个548个氨基酸的蛋白。它们的氨基酸序列和北美萤火虫(Photinus pyralis)的氨基酸序列分别有65.3%和65.9%的相似性，而彼此之间又有73.5%的相似性。两种在大肠杆菌中表达的荧光素酶均有很高的活性，它们的最大发光波长分别是566 nm和563 nm。同时表达的四种荧光素酶(L. ovalis、L. terminalis、Hotaria parvula和Pyrocoelia miyako)在不同pH下活性变化很大，四种荧光素酶在pH 6.5-7.5之间有比较高的活性，其中L. ovalis和P. miyako两种荧光素酶在pH 7.0时活性最高，而另两种在pH 7.5时活性最高。当pH大于8.0时，这四种荧光素酶的活性都散失很快，可见它们对pH变化非常敏感。序列分析和结构模拟发现，荧光素酶活性位点周围有六个非常保守的结构域，这六个保守区域包含了大多数在催化发光反应中与底物荧光素和ATP结合的氨基酸。L. terminalis萤火虫荧光素酶的三级结构与L. cruciata荧光素酶晶体结构非常相似，而L. ovalis荧光素酶的三级结构在AMP结合位点附近有两个偏离的环。

Formation and growth of Bryopsis hypnoides lamouroux regenerated from its protoplasts

Tissue culture, SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and spectra analysis were used for studying the aggregation mechanism of protoplasts from Bryopsis hypnoides Lamouroux and the discrepancy between the protoplast-regenerated plants and the wild type. The aggregation of protoplasts from B. hypnoides was observed in natural seawater and artificial seawater with different pH values, and the location and mechanism of the materials causing the aggregation were also studied. Results showed that the protoplasts could aggregate into some viable spheres in natural seawater and subsequently grow into mature individuals. Aggregation of the protoplasts depended exclusively upon the pH value (6-11), and the protoplasts aggregated best at pH 8-9. Some of the extruded protoplasts were separated into two parts by centrifugation: the pellet (PO) and the supernatant (PL). The PO could aggregate in artificial seawater (pH 8.3) but not in PL. No aggregation was found in PO cultured in natural seawater containing nigericin, which can dissipate the proton gradients across the membrane. These experiments suggest that the aggregation of protoplasts is proton-gradient dependent and the materials causing the aggregation were not in the vacuolar sap, but located on the surface or inside the organelles. Furthermore, the transfer of the materials across the membrane was similar to Delta pH-based translocation (Delta pH/TAT) pathway that occurs in the chloroplasts of higher plants and bacteria. Obvious discrepancies in both the total soluble proteins and the ratio of chlorophyll a to chlorophyll b between the regenerated B. hypnoides and the wild type were found, which may be related to the exchange of genetic material during aggregation of the organelles. In the process of development, diatom Amphora coffeaeformis Agardh attached to the protoplast aggregations, retarding their further development, and once they were removed, the aggregations immediately germinated, which showed that diatoms can affect the development of other algae.

The Bopyridae (Crustacea: Isopoda) parasitic on thalassinideans (Crustacea: Decapoda) from China

Eight species among six genera of bopyrid isopods (representing the subfamilies Pseudionmae and loninae) infesting thalassinideans from China are reported. Of these, four species are new to science: Gyge.fujianensis n. sp., Progebiophilits elongatus n. sp., Upogebione bidigitatus n. sp., and Procepon liuruiyui n. sp., infesting Upogebia major (de Haan), Nihonotrypaea japonica Ortmann, Upogebia carinicauda (Stimpson), and Austinogebia wuhsienweni (Yu). One species, lone cornuta Bate, 1864, is recorded for the first time from Chinese waters and from a new host. Pseudione longicauda Shiino, 1937, Gyge ovalis (Shiino, 1939), and Progebiophilus sinicus Markham, 1982, previously known from Hong Kong or Taiwan, are recorded for the first time from mainland China, extending their range north.

Salted fish products from the Coptic monastery at Bawit, Egypt: evidence from the bones and texts

Fish bone assemblages are described that were recently discovered in the storage area of two rooms, dated to the 7th century AD, from the monastery of Bawit, Egypt. The species composition, the reconstructed sizes of the fish and the find contexts show that this material represents pickled fish (salsamenta). This product was made in one case of medium-sized Clarias catfish, whereas another assemblage, found inside an amphora, consisted of small-sized fish, mainly cyprinids and alestiids. The latter product was stored in a Late Roman Amphora 5/6 of Palestinian origin, traditionally considered as a container for wine. The amphora was clearly re-used since the fish found in it are Nilotic species which excludes that the salsamenta came from outside Egypt. A few additional finds of fish inside amphorae were available, but due to the low number of bones it was unclear if salted fish products were stored in them. Textual information provided by ostraca and papyri from the same site shows that the monks exerted fishing activities themselves and also suggests that the production of pickled fish took place locally. One of the two Nilotic fish taxa (Labeo) that is specifically mentioned by written evidence is the most common ingredient found in the amphora with abundant fish remains. The paper ends with a brief summary of other faunal evidence for salted fish products from monastic and other historic sites in Egypt.

Los espinares de orIa de los carrascales supramediterráneos castellano-cantábricos

Se realiza un estudio fitosociológico de los espinares xerófilos que orlan los carrascales supramediterráneos castellano-cantábricos, describiéndose una nueva asociación para ellos: Amelanchiero ovalis-Spiraeetum obovatae. También se valida la subalianza Rosenion carioti-pouzinii y se presenta una tabla sintética de las asociaciones que hasta el momento la constituyen en la Península Ibérica.

Effect of high CO2 and ocean acidification on photosynthesis and response to oxidative stress in seagrasses

Climate change scenarios comprise significant modifications of the marine realm, notably ocean acidification and temperature increase, both direct consequences of the rising atmospheric CO2 concentration. These changes are likely to impact marine organisms and ecosystems, namely the valuable seagrass-dominated coastal habitats. The main objective of this thesis was to evaluate the photosynthetic and antioxidant responses of seagrasses to climate change, considering CO2, temperature and light as key drivers of these processes. The methodologies used to determine global antioxidant capacity and antioxidant enzymatic activity in seagrasses were optimized for the species Cymodocea nodosa and Posidonia oceanica, revealing identical defence mechanisms to those found in terrestrial plants. The detailed analysis and identification of photosynthetic pigments in Halophila ovalis, H.stipulacea, Zostera noltii, Z marina, Z. capricorni, Cymodocea nodosa and Posidonia oceanica, sampled across different climatic zones and depths, also revealed a similarity with terrestrial plants, both in carotenoid composition and in the pigment-based photoprotection mechanisms. Cymodocea nodosa plants from Ria Formosa were submitted to the combined effect of potentially stressful light and temperature ranges and showed considerable physiological tolerance, due to the combination of changes in the antioxidant system, activation of the VAZ cycle and accumulation of leaf soluble sugars, thus preventing the onset of oxidative stress. Cymodocea nodosa plants living in a naturally acidified environment near submarine volcanic vents in Vulcano Island (Italy) showed to be under oxidative stress despite the enhancement of the antioxidant capacity, phenolics concentration and carotenoids. Posidonia oceanica leaves loaded with epiphytes showed a significant increase in oxidative stress, despite the increase of antioxidant responses and the allocation of energetic resources to these protection mechanisms. Globally, the results show that seagrasses are physiologically able to deal with potentially stressful conditions from different origins, being plastic enough to avoid stress in many situations and to actively promote ulterior defence and repair mechanisms when under effective oxidative stress.

Spatio-temporal variation of microphytoplankton in the upwelling system of the south-eastern Arabian Sea during the summer monsoon of 2009

The phytoplankton standing crop was assessed in detail along the South Eastern Arabian Sea (SEAS) during the different phases of coastal upwelling in 2009.During phase 1 intense upwelling was observed along the southern transects (8◦N and 8.5◦N). The maximum chlorophyll a concentration (22.7 mg m −3) was observed in the coastal waters off Thiruvananthapuram (8.5◦N). Further north there was no signature of upwelling, with extensive Trichodesmium erythraeum blooms. Diatoms dominated in these upwelling regions with the centric diatom Chaetoceros curvisetus being the dominant species along the 8◦N transect. Along the 8.5◦N transect pennate diatoms like Nitzschia seriata and Pseudo-nitzschia sp. dominated. During phase 2, upwelling of varying intensity was observed throughout the study area with maximum chlorophyll a concentrations along the 9◦N transect (25 mg m−3) with Chaetoceros curvisetus as the dominant phytoplankton. Along the 8.5◦N transect pennate diatoms during phase 1 were replaced by centric diatoms like Chaetoceros sp. The presence of solitary pennate diatoms Amphora sp. and Navicula sp. were significant in the waters off Kochi. Upwelling was waning during phase 3 and was confined to the coastal waters of the southern transects with the highest chlorophyll a concentration of 11.2 mg m−3. Along with diatoms, dinoflagellate cell densities increased in phases 2 and 3. In the northern transects (9◦N and 10◦N) the proportion of dinoflagellates was comparatively higher and was represented mainly by Protoperidinium spp., Ceratium spp. and Dinophysis spp.

Roman diet and trade: evidence from organic residues on pottery sherds recovered at the Roman town of Calleva Atrebatum (Silchester Hants.)

The analysis of organic residues from pottery sherds using Gas-Chromatography with mass-spectroscopy (GC-MS) has revealed information about the variety of foods eaten and domestic routine at Silchester between the second and fourth–sixth centuries A.D. Two results are discussed in detail: those of a second-century Gauloise-type amphora and a fourth-century SE Dorset black-burnished ware (BB1) cooking pot, which reveal the use of pine pitch on the inner surface of the amphora and the use of animal fats (ruminant adipose fats) and leafy vegetables in cooking at the Roman town of Silchester, Hants.

Systematic structural studies of iron superoxide dismutases from human parasites and a statistical coupling analysis of metal binding specificity

Superoxide dismutases (SODs) are a crucial class of enzymes in the combat against intracellular free radical damage. They eliminate superoxide radicals by converting them into hydrogen peroxide and oxygen. In spite of their very different life cycles and infection strategies, the human parasites Plasmodium falciparum, Trypanosoma cruzi and Trypanosoma brucei are known to be sensitive to oxidative stress. Thus the parasite Fe-SODs have become attractive targets for novel drug development. Here we report the crystal structures of FeSODs from the trypanosomes T. brucei at 2.0 angstrom and T. cruzi at 1.9 angstrom resolution, and that from P. falciparum at a higher resolution (2.0 angstrom) to that previously reported. The homodimeric enzymes are compared to the related human MnSOD with particular attention to structural aspects which are relevant for drug design. Although the structures possess a very similar overall fold, differences between the enzymes at the entrance to the channel which leads to the active site could be identified. These lead to a slightly broader and more positively charged cavity in the parasite enzymes. Furthermore, a statistical coupling analysis (SCA) for the whole Fe/MnSOD family reveals different patterns of residue coupling for Mn and Fe SODs, as well as for the dimeric and tetrameric states. In both cases, the statistically coupled residues lie adjacent to the conserved core surrounding the metal center and may be expected to be responsible for its fine tuning, leading to metal ion specificity.

Revisão de grupo E. rufomarginata do gênero Edessa fabricius, 1803 (Heteroptera pentatomidae, Edessinae)

O gênero Edessa Fabricius, 1803 pertence à subfamília Edessinae de Pentatomidae e possui um grande número de espécies já descritas (259), sendo provavelmente o maior de Heteroptera e um dos menos estudados desta família. Neste trabalho foi revisado o grupo denominado Edessa rufomarginata com base em caracteres morfológicos, principalmente da genitália de ambos os sexos. Para análise cladística do grupo foi montada uma matriz de dados com 25 caracteres da morfologia geral e da genitália. A polarização dos caracteres foi realizada através do método de comparação com grupo externo. Para análise dos dados obtidos foi utilizado o programa Hennig86, os algoritimos empregados foram “ie*” e “ne”, sendo que como interface gráfica com Windows®, foi utilizado o programa Tree Gardener V.2.2. A metodologia empregada propiciou o estudo das variações morfológicas em Edessa rufomarginata (De Geer, 1773), o que resultou na revalidação de Edessa marginalis (Dallas, 1951) e Edessa albomarginatus (Stål, 1855). Estas espécies foram redescritas bem como outras cinco a saber: Edessa abdominalis Erichson, 1848; Edessa corallipes Erichson, 1848; Edessa aulacosterna Stål, 1872; Edessa ovalis Stål, 1872 e Edessa nigropunctata Berg, 1884. Sete novas espécies foram descritas: Edessa brasiliensis sp. nov., Edessa castaneolineata sp. nov., Edessa cerradensis sp. nov., Edessa chapadensis sp. nov., Edessa luteovenulata sp. nov., Edessa rufodorsata sp. nov. e Edessa viridisdorsata sp. nov. Na análise cladística um único cladograma foi obtido, com 45 passos; Índice de Consistência = 60 e Índice de Retenção = 80; a monofilia do grupo foi corroborada por sete sinapomorfias.

Global stratigraphy, palaeobiogeography and palaeoecology of Albian-Maastrichtian pithonellid calcispheres: impact on Tethys configuration

This study reviews the stratigraphy, palaeobiogeography and palaeoecology of some important Albian-Maastrichtian pelagic calcispheres: Bonetocardiella conoidea, Pithonella ovalis, P. perlonga, P. sphaerica and P. trejoi. It also presents a significant new data set on these organisms from the western South Atlantic Ocean. The group reached its acme simultaneously all over the world during the highest Cretaceous sea level in late Albian to Coniacian times. A strong association also existed between the maximum temperature and the salinity of the Tethyan water mass and the climax of these opportunistic microfossils. Their remarkable presence along the Brazilian and west African margins during the Albian, in association with other typical Tethyan pelagic biotic elements, indicates that during this period the northern South Atlantic was a long, narrow arm of the Tethys Sea. (C) 2000 Academic Press.