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1.
采用平板水解圈法对分离自张家口天漠沙土的嗜盐和耐盐细菌(含放线菌)进行淀粉酶活性筛选,运用基于16S rRNA基因序列的分析方法对活菌株进行系统发育多样性分析.结果表明,76个受试菌株中,有34株淀粉水解酶活性呈阳性(44.7%),其中有6株具有较强的淀粉水解酶活性;系统发育分析显示34个阳性菌株类群多样性和物种多样性较高,可以归为18个物种,分属于细菌域(Bacteria)的2门(Actinobacteria,Firmicutes)2科(Streptomycetaceae,Bacillaceae)8属(Streptomyces,Bacillus,Gracilibacillus,Halobacillus,Oceanobacillus,Piscibacillus,Thalassobacillus,Virgibacillus);产淀粉酶活性较强的6株菌均属于厚壁菌门(Firmicutes)芽孢杆菌科(Bacillaceae),分属于该科的3个属.其中菌株JSM 1684012,JSM 1684041和JSM 1685098属于芽孢杆菌属(Bacillus);JSM 1684067和JSM 1685082属于纤长芽孢杆菌属(Gracilibacillus);JSM 1685081属于喜盐芽孢杆菌属(Halobacillus).以上结果说明分离自张家口天漠沙土的嗜盐和耐盐菌中存在较高比例的产淀粉酶菌株,且这些菌株具有较高的类群多样性和物种多样性.  相似文献   

2.
利用平板涂布法分离会仙湿地底泥可培养原核微生物,共获得65个分离株,基于细菌16S rRNA基因序列的相似性和系统聚类分析显示,它们分属4个门,12个属,24个种,包括厚壁菌门的芽孢杆菌属Bacillus、类芽孢杆菌属Paenibacillus、Fictibacillus属、Lysinibacillus属和肠球菌属Enterococcus;放线菌门的链霉菌属Streptomyces和红球菌属Rhodococcus;变形菌门的假单胞菌属Pseudomonas、寡养单胞菌属Stenotrophomonas、泛菌属Pantoea、代尔夫特菌属Delftia以及拟杆菌门的金黄杆菌属Chryseobacterium。分离株中芽孢杆菌属的菌株占53.85%,为优势菌群,其在有机物含量高的条件下会大量繁殖,与湿地富营养化特征相吻合;分离的微生物中含10株4种条件致病性菌,占分离株的15.38%,有机砷耐受菌株30株12种,占46.15%,表明该生态环境已被人为活动严重影响。此外,还分离获得对农药五氯硝基苯(PCNB)耐受性在300 mg/L以上的菌株1株,它们的出现与当地农药与化肥的滥用有着直接关系。  相似文献   

3.
连云港台南盐田中嗜盐和耐盐菌群分布的调查   总被引:3,自引:0,他引:3  
2001年、2002年冬春夏3季在连云港台南盐场取卤水和底泥样品,对嗜盐菌和耐盐菌的分布状况进行调查.结果表明,不同盐度(6.6%-32.3%)盐池中栖息着不同的菌群,夏季嗜盐菌和耐盐菌数量较高,主要以盐单胞菌属、海球菌属、盐水球菌属等非芽孢菌为优势菌,低盐度(6.6%-9.9%)池中耐盐菌数量高于嗜盐菌,中盐度(13.8%-17.4%)池中耐盐菌数量接近嗜盐菌,高盐度(20.2%-32.3%)池中主要为极端嗜盐菌.此外,底泥中嗜盐菌和耐盐菌的数量一般高于卤水中.  相似文献   

4.
《河南科学》2017,(1):78-82
通过脱脂牛奶平板法从深海海泥中筛选到35株在低温条件(4℃)下具有蛋白酶活性的菌株,并对这35株菌进行了分子生物学鉴定和酶活测定,发现这35株菌分别属于动性球菌属(Planococcus)、芽孢杆菌属(Bacillus)、Fictibacillus、发光杆菌属(Photobacterium)、冷蛇菌属(Psychroserpens)、微小杆菌属(Exiguobacterium)、交替假单胞菌属(Pseudoalteromonas).选择各个属活性最高的菌株为研究对象,以酪蛋白为反应底物对其所产蛋白酶粗酶液酶学性质进行初步研究.结果表明,动性球菌属菌株PL4-1所产蛋白酶酶活最适反应温度为40℃,10℃时可保持50%以上的酶活,在60℃时酶活下降至40%以下,为典型的低温蛋白酶.  相似文献   

5.
四种华重楼内生细菌的初步研究   总被引:1,自引:0,他引:1  
从华重楼(Paris polyphylla var Chinensis)的新鲜块茎中分离得到107株内生菌.对这107株菌进行了液体培养,经初步检测鉴定,有6株菌产生薯蓣皂甙或其类似物等甾体皂甙,对其中4株菌的形态学和理化特征进行了研究,确定这4株菌分别属于德克斯氏菌属(Derxia sp)、芽孢杆菌属(Bacillus sp)、动性球菌属(Planococcus sp)、肠杆菌属(Enterobacter sp).  相似文献   

6.
主要研究西沙群岛野生诺尼叶片中可培养内生菌的多样性。利用常规平板分离方法进行菌株分离。通过测定真菌核糖体基因翻译间隔序列(ITS序列)和细菌16S r DNA基因序列,结合系统发育研究对所分离菌株进行鉴定分析。共分离到32株内生菌,分为19种。其中2种霉菌,共2株,分别属于炭层菌属(Nemania sp.)和毛壳菌属(Chaetomium sp.);细菌17种,共30株,分别属于芽孢杆菌属(Bacillus sp.)、赖氨酸芽孢杆菌属(Lysinibacillus sp.)、微球菌属(Micrococcus sp.)、土地芽孢杆菌属(Terribacillus sp.)、肠杆菌属(Enterobacter sp.)、黄单胞菌属(Xanthomonas sp.)、黄杆菌属(Flavobacterium sp.)等7个已知属,其中芽孢杆菌属(Bacillus sp.)为绝对优势属,共20株,11种。  相似文献   

7.
利用反硝化培养基分离得到24株菌株,通过好氧吸磷试验和硝酸盐还原产气试验,确定其为反硝化聚磷菌.16SrRNA基因测序和系统发育分析结果显示,24株反硝化聚磷菌可归于5个不同的属,分别是芽孢杆菌属(Bacillus)、丛毛单胞菌属(Comamonas)、普罗维登斯菌属(Providencia)、假单胞菌属(Pseudomonas)和假苍白杆菌属(Pseudochrobactrum).  相似文献   

8.
为了研究江苏地区鲫鱼养殖池塘底泥细菌菌群结构与多样性,通过高通量测序技术对2017年8-10月间采集的江苏省不同区域养殖池塘底泥中所有细菌的16S rRNA V3-V4基因进行扩增测定,分析了底泥菌群结构特征;并通过平板计数法和选择培养基法检测池塘底泥中细菌总数和主要常见菌。结果表明,49个样品高通量测序共获得有效序列2152956条,可归为17735个分类操作单元(OTUs);物种注释结果显示,鲫鱼养殖池塘底泥中具有较高的菌群多样性,检测到的细菌归属于29个门类,所有池塘底泥都具有主要门类为变形菌门、绿弯菌门、厚壁菌门、拟杆菌门、水生古细菌门、酸杆菌门、放线菌门、硝化螺旋菌门、螺旋菌门、芽单胞菌门、蓝细菌门、浮霉菌门、疣微菌门等。在属的水平上主要以硫杆菌属,乳酸球菌属,硫氧化菌,甲烷菌,地杆菌属,假单胞菌属,厌氧粘杆菌属,甲烷绳菌属,芽孢杆菌属等为主;所有池塘底泥共有菌主要有乳酸球菌属,甲烷菌,盐单胞菌,芽孢杆菌,红杆菌属,链球菌属,肉杆菌属,微小杆菌属,土芽孢杆菌属等。通过细菌培养发现,池塘底泥中常见益生菌如乳酸菌、芽孢菌具有较高的比例。可见鲫鱼养殖池塘底泥菌群结构及组成具有多样性,不同养殖池塘中共有的细菌可作为益生菌开发的参考菌株。  相似文献   

9.
本试验从沈阳重型机械厂煤气发生站废水处理厂活性污泥中三次分期取样,采用常规的细菌分离方法分离出62株细菌,经鉴定它们分别属于假单胞菌属、芽孢杆菌属、气单孢菌属、邻单胞菌属和产碱杆菌属,经过训化,得到9株抗高浓度酚和降解酚浓度较强的优良菌株,这些菌株分别属于邻单胞杆菌属和假单胞杆菌属.  相似文献   

10.
采集湖北地区代表性重楼种植园的重楼植株,并从0.1 g根中分离获得115株内生细菌. 16S rDNA序列分析结果表明,这些内生细菌归属于3个门、5个纲、7个目、11个科和12个属.其中,短食单胞菌属(Stenotrophomonas)为优势菌属(33.9%),而肠杆菌属(Enterobacteriaceae)、潘多拉菌属(Pandoraea)、克雷伯氏菌属(Klebsiella)、短杆菌属(Brevibacterium)、类芽孢杆菌属(Paenibacillus)、拟杆菌属(Bacteroides)、波氏菌属(Bosea)为劣势属.进一步通过与小麦幼苗共培养,筛选到4株促生菌,包括克雷伯氏菌属菌株HBR11019、假单胞菌属菌株HBR11015和HBR11017、芽孢杆菌属菌株HBR31040.其中HBR11019菌株的促生作用最强,与其共培养的小麦幼苗的株高、根长、鲜重、侧根数目分别是对照的2.6倍、2.1倍、5.7倍和1.0倍.本研究为深入分析不同产区重楼内生菌的差异以及利用促生菌改良重楼种植技术的研究奠定了基础.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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