小球藻Chlorella variabilis NC64A二酰甘油酰基转移酶基因的克隆表达与功能研究

为了揭示二酰甘油酰基转移酶(DGAT)在小球藻油脂合成过程中的作用,对单细胞小球藻Chlorella variabilis NC64A的二酰甘油酰基转移酶进行原核克隆表达及功能初步研究。结果表明,其编码序列为894bp,编码297个氨基酸,表达蛋白的表观分子量为33 k Da,p I 9.48。保守结构域分析表明,该蛋白属于Lysophospholipid acyltransferases(LPLATs)超家族,具有二酰甘油酰基转移酶活性,序列位点H68,L71,F76,R94,I97和GAA(144?146)组成特定的酰基受体结合口袋,能够结合酰基?酰基载体蛋白(ACP)或者酰基辅酶A上的酰基,催化三酰甘油合成的最后一步。表达蛋白与Ss PDAT和At PDAT的序列相似性分别为32%和24%,表明该蛋白可能具有磷脂酰甘油酰基转移酶(PDAT)活性,能利用磷脂上的酰基合成三酰甘油。因此,采用薄层层析方法以L-α-磷脂酰胆碱和1,2-二油酰-sn-甘油为底物,检测到其确实具有PDAT活性,表明限氮条件下NC64A中DGAT的PDAT活性可能促进了膜脂降解耦合三酰甘油的合成。

Hyperspectral imaging technology to detect the vigor of thermal-damaged Quercus variabilis seeds

This study investigated the feasibility of hyperspectral imaging techniques to estimate the vigor of heatdamaged Quercus variabilis seeds.Four thermal damage grades were classified according to heat treatment duration(0,2,5,and 10 h).After obtaining hyperspectral images with a 370–1042 nm hyperspectral imager that included visible and near infrared light,germination was tested to confirm estimates.The Savitzky–Golay(SG)second derivative was used to preprocess the spectrum to reduce any noise impact.The successive projections algorithm(SPA),principal component analysis,and local linear embedding algorithm were used to extract the characteristic spectral bands related to seed vigor.Finally,a model for seed vigor classifi-cation of Q.variabili s based on partial least squares support vector machine(LS-SVM)with different spectral data sets was developed.The results show that the spectrum after SG second derivative preprocessing was better for developing the model,and SPA performed the best among the three feature band selection methods.The combination SG second derivative-LS-SVM provided the best classification model for Q.variabilis seed vigor,with the prediction set reaching 98.81%.This study provides an important basis for rapid and nondestructive assessment of the vigor of heat-damaged seeds using hyperspectral imaging techniques.

Beak Measurements of Octopus (Octopus variabilis) in Jiaozhou Bay and Their Use in Size and Biomass Estimation

Cephalopods play key roles in global marine ecosystems as both predators and preys.Regressive estimation of original size and weight of cephalopod from beak measurements is a powerful tool of interrogating the feeding ecology of predators at higher trophic levels.In this study,regressive relationships among beak measurements and body length and weight were determined for an octopus species(Octopus variabilis),an important endemic cephalopod species in the northwest Pacific Ocean.A total of 193 individuals(63 males and 130 females) were collected at a monthly interval from Jiaozhou Bay,China.Regressive relationships among 6 beak measurements(upper hood length,UHL;upper crest length,UCL;lower hood length,LHL;lower crest length,LCL;and upper and lower beak weights) and mantle length(ML),total length(TL) and body weight(W) were determined.Results showed that the relationships between beak size and TL and beak size and ML were linearly regressive,while those between beak size and W fitted a power function model.LHL and UCL were the most useful measurements for estimating the size and biomass of O.variabilis.The relationships among beak measurements and body length(either ML or TL) were not significantly different between two sexes;while those among several beak measurements(UHL,LHL and LBW) and body weight(W) were sexually different.Since male individuals of this species have a slightly greater body weight distribution than female individuals,the body weight was not an appropriate measurement for estimating size and biomass,especially when the sex of individuals in the stomachs of predators was unknown.These relationships provided essential information for future use in size and biomass estimation of O.variabilis,as well as the estimation of predator/prey size ratios in the diet of top predators.

Infl uence of the slope aspect on the ectomycorrhizal fungal community of Quercus variabilis Blume in the middle part of the Taihang Mountains,North China

The slope aspect is one of the most critical topographic factors in mountainous areas.Little is known,however,about the eff ect of the aspect on the ectomycorrhizal(ECM)fungal community.Additionally,we know very little about the composition of ECM fungal communities associated with Quercus variabilis,which is widely distributed in East Asia.In this study,we compared the richness,community composition,and exploration types of ECM fungi associated with Q.variabilis between predominantly south-and north-facing slopes in the Taihang Mountain,North China for the fi rst time.DNA was extracted from the root tips of Q.variabilis,and Illumina MiSeq sequencing was used to identify ECM fungi.In total,168 operational taxonomic units belonging to 28 genera were detected,and the ECM community was found to be dominated by Russula,Inocybe,Tomentella,Scleroderma,and Cortinarius.Compared with the north-facing slopes,the ECM communities on the south-facing slopes had higher diversity.The community composition and exploration types were directly aff ected by the slope aspect.Also,the aspect-induced edaphic variables,such as total phosphorus,total nitrogen,total potassium,pH,and soil water content,were important sources of variation in ECM fungal richness and distributions of exploration types.Diff erent genera tended to be distributed in various slope aspects.Cenococcum,Genea,and Clavulina were signifi cantly enriched in north-facing slopes,while Geopora,Helvelosebacina,Scleroderma,Gyroporus,Astraeus,Boletus,Tricholoma,Hebeloma,Cortinarius and unclassifi ed Thelephoraceae were more abundant in south-facing slopes.Hydrophobic ECM fungi were obviously enriched in the south-facing slope,but there was no statistical diff erence between hydrophilic among the south-and north-facing slopes.Our study deepened our knowledge of the aspect-driven variation in ECM fungal communities associated with Q.variabilis.

土耳其海绵Ircinia variabilis中溴代生物碱的分离与鉴定

目的研究土耳其海绵Ircinia variabilis的化学成分。方法采用多种色谱方法分离纯化,依据理化性质、波谱数据和文献对照的方法鉴定结构。结果从土耳其海绵Ircinia Variabilis提取物中分离鉴定了5个溴代生物碱类化合物:fistularin-3(1),2-oxazolidinone(2),(E)-1-acetamide-3,5-dibromo-4-ethoxy-4-methoxy-1-hydroxy-2,5-cyclohexaddienone(3),(Z)-1-acetamide-3,5-dibromo-4-ethoxy-4-methoxy-1-hydroxy-2,5-cyclohexaddienone(4),3,5-dibromotyrosine(5)。结论化合物1从该种内首次分离得到,化合物2～4从该种属中首次分离得到。

Effects of Root Cutting on Morphological Characteristics and Endogenous Hormone Levels of Quercus variabilis Seedlings

The objective of this study was to investigate the effects of root cutting stress on the dynamic changes of endogenous hormone content and growth characteristics of Quercus variabilis roots,and to explore the physiological role of endogenous hormones in regulating root-crown interactions in the short term.The morphological characteristics and endogenous hormone contents of normal roots(no root cutting,CK)and cut roots(cut by 1/3 of the length of the main root,RP)were determined by liquid chromatography,which was combined with mass spectrometry at different levels of different developmental stages.The results showed that the root growth indexes and root endogenous hormones in the RP group were superior to those in the CK group.Through comprehensive analysis of endogenous hormones,it was found that the crosstalk of IAA,JA,ABA and SA could activate the root growth defense.After the root cutting treatment,the root growth of Quercus variabilis seedlings could compensate for the inhibition of taproot growth by promoting lateral root growth.The growth and development of compensatory lateral roots contribute to the increase the total root length of plants,thus promoting the absorption of water and nutrients.It is speculated that plant hormones may be the key factors affecting their development,but this is not only related to the content of a single hormone,but more importantly,it is the interaction between various hormones.

H_2 PRODUCTION BY ANABAENA VARIABILIS MUTANT IN COMPUTER CONTROLLED TWO-STAGE AIR-LIFT TUBULAR PHOTOBIOREACTOR

A 4.34 liter two stage air lift photobioreactor incorporating Anabaena variabilis ATCC29413 mutant PK84 was used to study H 2 production. Results showed that H 2 production increased with increasing light intensity from 47 μE/(m 2·s) up to 190 μE/(m 2·s), but that further increase of light intensity decreased the H 2 production because of the inhibition due to the high pO 2. The data also indicated that longer argon gas charge resulted in more H 2 produced due to the increase of nitrogenase activities and heterocyst frequency, and that more than 1.3 L net H 2 was produced from this computer controlled photobioreactor.

HYDROGEN PHOTOPRODUCTION OF A.VARIABILIS INCORPORATED IN A PHOTOBIOREACTOR

H2 photoproduction and nitrogenase activities in two strains of Anabaena variabilismarked wild type ATCC 29413 and mutant PK84 exposed to thermal stress (temperature higher than thenormal incubation temperature of 30℃) were studied. Cultures of both strains collected from any intervalof logarithmic growth phase exhibited high H2 photoproduction and nitrogenase activities when exposed tolimited time heat shock during the assay process. In contrast, the algal H2 photoproduction rate of bothstrains fluctuated with long term thermal stress caused hy increasing the growth temperature from 30℃ to36℃.The changes of nitrogenase (the key H2 photobiosynhetic enzyme) activities in the mutant PK84showed variation tendency similar to that of H2 photoproduction during exposure to thermal stress, indicat-ing that fluctuation of H2 photopnduction in the mutant was mainly due to the variation of nitrogenase ac-tivities. A temporary maximal H2 photoproduction in the mutant PK84 (wild type ATCC29413 ) was ob-served when cells po at 36℃ for 14 (6) days. However, the responses of nitrogenase activities in thewild type to thermal stress were not completely similar to those in the mutant in spite of similar variationsof H2 photoproduction in both strains. The data obtained in these studies suggested tha the activities ofother enzymes (in the wild strain) involved in H2 photoproduction were affected by thermal stress since H2photoporduction maximized or dropped to 0 without variation tendency similar to that of nitrogenase activi-ties.Furthermore, an enhancement of H2 photoproduction speed of the mutant strain cultured in a 4.4 Llaboratory photobioreactor was also observed when it was subjected to short time continuous charge of ar-gon, and temperature rise.All these results indicated that high temperature plays an important role in the photo-autotrophic H2photoproduction, and that long term thermal stress is unfavourable for net H2 phooproduction in bothstrains of A. variabilis though short-time heat shock is conducive to H2 photoproduction.

Effects of Increased Salinity on Growth, Development and Survival in Early Life Stages of the Green Toad Bufotes variabilis (Anura: Bufonidae)

This study examined the effects of increased salinity on growth, development and survival of the Green toad, Bufotes variabilis during embryonic, hatching and early larval periods. Eggs from a single cohort of B. variabilis were subjected to acute and chronic toxicity tests for water salinity ranging from 0.20 to 10 g of salt per liter. Results obtained from this study showed that salinity over 3.70 g/l increased embryonic mortality and reduced percentage of hatching and survival rate of larvae. As larvae tolerated salinity 0.20 to 3.70 g/l with highest survival, but salinity of 10 g/l caused mortality of all individuals within 12 h, 7.70-8.70 （g/l） within 4.5 days, 5.70-6.70 g/l within 10 days and 4.70 （g/l） were tolerated within 14 days. Salinity less than 0.70 g/l did not affect survival and hatching success of the embryos. After a 3-week experiment, size of larvae exposed to salinities over 0.70 g/l was lower compared to larvae reared at lower salinity levels. Meanwhile increases in salinity more than 3.70 g/l caused extension in the hatching period. Larvae reared at salinity of 3.70 to 4.70 g/l had morphological abnormalities, such as distortion of tail.

A new cycloartane nortriterpenoid from Quercus variabilis Blume

The leaves and stems of Quercus variabilis Blume afforded a new cycloartane nortriterpenoid, 3α-acetyloxy-4α, 14α-dimethyl- 9β, 19-eycloergost-24-oic acid （1）, along with five known compounds （2-6）. The structure of 1 was elucidated by 1D and 2D NMR and mass spectroscopy. 2009 Qi Shi Sun. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

Classification of Natural Types of Quercus variabilis

[Objectives]The paper was to classify natural types of Quercus variabilis and to study its regularity of variation.[Methods]Through the analysis of correlation coefficient matrix of tree age,DBH,tree height,breast height and bark thickness,petiole length,leaf width and leaf length,the breast height and bark thickness and petiole length were chosen as the main indices for classifying natural types of Q.variabilis.[Results]There were 4 natural types of Q.variabilis in Shaanxi Province,including long-petiole-thick-bark type,short-petiole-thick-bark type,long-petiole-thin-bark type and short-petiole-thin-bark type.The short-petiole-thick-bark type accounted for the largest proportion in Q.variabilis population(34.44%).On the northern slope of Bashan Mountains and the Huanglong Mountains,the short-petiole-thick-bark type was the dominant type,while on the northern slope of Qinling Mountains the long-petiole-thick-bark type accounted for a larger proportion.[Conclusions]This study will provide a basic foundation for making full use of excellent types of Q.variabilis natural resources.

A heterozygous mutation in GJA1 gene in Chinese family with serious erythrokeratodermia variabilis et progressive

To the Editor:Erythrokeratodermia variabilis (EKV;MIM 133200) is characterized by the coexistence of transient,figurate,erythematous patches,and localized keratotic hyperkeratosis.EKV shows marked phenotypic heterogeneity,even within kindreds bearing the same diseasecausing mutation.[1] The term EKV et progressiva (EKVP) is a severe variant of EKV and has been proposed to encompass the diversity of phenotypes,ranging from limited hyperkeratotic plaques and erythematous patches to severe progressive symmetric erythrokeratodermia which can feature more generalized cutaneous involvement.

Isolation and characterization of rod-core complex from the phycobilisome of Anabaena variabilis

THE phycobilisomes (PBSs) of A. variabilis, like most other cyanobacteria and red alage,are hemi-discoidal. They contain various phycobiliproteins such as phycoerythrocyanin(PEC), C-phycocyanin (C-PC) and allophycocyanin (APC), and the energy transfer flowscan be examplified by the following scheme: PEC→C-PC→APC. Although the high resolu-tion crystal structures of PEC, C-PC and APC have been determined by X-ray method,

Evaluation of antibacterial activity of zinc oxide nanoparticles synthesized using phycobilins of Anabaena variabilis NTSS17

Objective:To evaluate the antibacterial activity of zinc oxide nanoparticles synthesized using phycobilins of Anabaena variabilis NTSS17.Methods:The cyanobacterial isolate was collected from paddy field and morphologically identified as Anabaena variabilis NTSS17,that produces a pigment i.e.phycobiliproteins.The biosynthesized zinc nanoparticles were characterized by different spectroscopic and analytical techniques such as UV-visible spectrophotometer,Fourier transform infrared spectroscopy and X-ray diffraction which confirmed the formation of zinc nanoparticles.Results:Antibacterial activity of zinc oxide nanoparticles was examined against Escherichia coli,Rhodococcus rhodochrous and Pseudomonas aeruginosa.The maximum zone of inhibition occurred at 5 mg/1000 mL concentration of zinc oxide nanoparticles.Conclusions:Due to potent antimicrobial and intrinsic properties of zinc oxide,it can be actively used for biomedical applications.

Erythrokeratoderma variabilis in a 3-year-old child:a satisfactory response to treatment with oral acitretin and topical 0.025% tretinoin cream

Introduction Erythrokeratoderma variabilis is a rare autosomal dominant genodermatosis that usually appears within the first year of life, but may arise later in childhood. EKV was described by Mendes da Costa in 1925(1)Clinical characteristics of EKV consist of irregularly-shaped, erythematous, scaly patches and hyperkera-totic plaques.

树枫杜鹃菌根真菌分离与鉴定

杜鹃花科（Ericaceae）植物约75属,1 350余种,主产南非和中国西南及西部,我国产20属,约800余种。杜鹃花属（Rhododendron）是杜鹃花科植物中最大的一个属,我国约产600余种,全国均有分布,尤其以四川、云南和贵州的种类最多[1]。

Diversity of filamentous fungi in organic layers of two forests in Zijin Mountain

A study was conducted to evaluate the cultivable filamentous fungal diversity in organic layers (L, F, and H layers) and A1 layer of two main forest types, Pinus massoniana and Liguidambar formasana mixed forest and Quercus variabilis forest, in Zijin Mountain(325?N, 11848?E), Nanjing, China. A total of 67 taxa comprising 56 Deuteromycetes, 3 Zygomycetes, 5 Asco-mycetes and 3 unidentified fungi were recognized from samples from the forest floor of the two forest types. The most abundant group was Deuteromycetes. The dominant genera in both forests were Alternaria sp., Aspergillus sp., Cladosporium sp., Mucor sp., Penicillium sp., Rhizopus sp., Gliocladium sp. and Trichoderma spp. The fungal diversity was higher in the mixed forest than that in Q. variabilis forest. For both forest types, the maximum fungal diversity was found in layer F and there existed significantly different in fungal diversity between layer F and layer L. In the mixed forest, richness of fungi isolated from needle litter (P. massoniana) was lower than that from leaf litter (L. formasana). The richness of fungi from needle litter increased with the in-crease of forest floor depth, but for leaf litter, the fungal diversity decreased with the depth of forest floor. The co-species of fungi from the two forest types, as well as from two kinds of litters in mixed forest, increased with the depth of the forest floor. The succession of fungi along with the process of decomposition was discussed here. The results also showed that litter quality was a critical factor affecting fungal diversity.

新型抗广谱性除草剂草甘膦转基因油菜的创制及其鉴定

草甘膦是世界上应用最广泛的广谱性除草剂,目前我国还没有自主知识产权的抗草甘膦油菜品种。本研究利用农杆菌介导的油菜下胚轴遗传转化方法,将新型抗草甘膦基因I.variabilis EPSPS转入甘蓝型油菜品系J9707中,获得了126株阳性转化株,阳性率为97.0%。这些转化单株中的T-DNA插入以单拷贝为主(占44.8%)。通过反向PCR确定了EPS-2、EPS-6和EPS-7等油菜转化体中T-DNA插入位置,并设计转化体特异性引物对它们的T0~T3代材料进行检测,证明了它们的T-DNA在基因组水平上整合的稳定性。RNA和蛋白水平的表达分析证实,I.variabilis EPSPS转基因及其蛋白产物在各转化株系不同世代能够稳定表达。苗期进行不同剂量的除草剂喷施处理发现,EPS-1、EPS-2、EPS-5、EPS-6和EPS-7等株系可耐受4倍田间推荐使用剂量的草甘膦。本研究所创建的新型抗草甘膦油菜种质资源将为我国抗除草剂油菜品种培育奠定了重要基础。

截根育苗技术对栓皮栎侧根生长的影响

本文敍述了栓皮栎的重要用途和经济价值以及截根育苗技术对栓皮栎幼苗侧根生长的影响,采用截根育苗技术,苗木侧根平均数量由14条增加到35条,截根育苗侧根数量较常规育苗提高了250.0%;侧根平均长度由8cm提高到12cm,截根育苗侧根长度较常规育苗提高了150.0%。

陕西商南县栓皮栎林分评价与管理(英文)

The present study was conducted within the frame of the Sino-German project "Rehabilitation of degraded land ecosystems in the mountainous area of the Southern Shaanxi Province,China".The study deals with the assessment of the potential of oak coppices as well as the evaluation of the socioeconomic conditions in the Shangnan County.The ultimate objective of the study is to provide recommendations on the sustainable management of forest resources,which does not only aim to improve the environmental situation but also to satisfy the demands of the local rural residents.The study was based on 30 samples of oak coppices stands,which were randomly selected within an area of a size of 20 km × 20 km.In each selected stand,the mature stand and understory regeneration were investigated in depth.For the socio-economic survey,175 households from 11 villages were randomly selected.Results revealed that the stocking capacity of the cork oak coppices reaches 120 m3/ha in average at the older age classes(≥25 years) even after frequent timber harvest.High potential for productivity was indicated by the availability of sufficient vigorous individuals at different age classes.In addition,the understory regeneration was sufficient in density(19,000±133 individual/ha) and consisted of diverse valuable native-species(17 species within a survey area of 400 m2).The results of the assessment of the oak coppices provided possibilities for some practices that can be recommended towards sustainable management of such stands.On the other hand,results of the socioeconomic study showed a high degree of acceptance among the local inhabitants(79% of the total households) to change traditional land use,providing an enhancement of their economic situation.