Prevalence of Bacillus sp. among the biofilm forming community on Ti surface in marine environment     

PRIYA Chokkalingam  ARAVIND Ganessin  THILAGARAJ Wilson Richard 《海洋学报(英文版)》2017,36(6):89-94

Prevalence of bacterial species involved in biomineralization of manganese on titanium (Ti) surfaces in marine environment was revealed in this research work. This study involves one year sea water exposure of Ti and their periodical biofilm characterization was carried out to quantify the manganese oxidizing bacterial (MOB) presence in the biofilm formed on titanium surfaces. The total viable count study of Ti coupons exposed to sea water for one year resulted in 60% of the MOB in overall biofilm population. The biochemical characterization of MOB isolates were performed for the genus level identification of the seven bacterial isolates. Further, the seven strains were subjected to 16S rRNA gene sequencing. Evolutionary analysis was performed using MEGA 7 to obtain closely related strains within the groups. The manganese oxidizing ability of the bacterial isolates were determined with Leucoberbelin Blue Assay (LBB) and Atomic Absorption Spectroscopy studies (AAS). The results show that among the isolated marine MOB species, Bacillus sp. and Leptothrix sp. have the maximum Mn oxidizing property. The microtitre plate assay was performed to determine the biofilm forming ability of the isolated marine MOB species. All the results have confirmed the prevalence of Bacillus sp. among the biofilm colonizers on Ti surfaces when exposed in sea water.  相似文献   

施氏鲟Asnanos1基因序列分析及其在雌雄不同组织中表达     

肖懿哲  朱友芳  孙玉龙  张鑫  张子平  王艺磊 《海洋科学》2017,41(4):17-23

本研究首先从施氏鲟(Acipenser schrenckii)性腺转录组中获得nanos1(Asnanos1)基因全长c DNA,并对其序列的准确性和特征分别进行PCR验证和生物信息学分析。进一步利用荧光定量RT-PCR技术检测Asnanos1基因在雌、雄施氏鲟的性腺、心脏、鳃、脑、肾、肝脏、脾脏等组织中的表达量。利用荧光定量RT-PCR技术检测Asnanos1基因在雌、雄施氏鲟的性腺、心脏、鳃、脑、肾、肝脏、脾脏等组织中的表达量。结果显示:Asnanos1的c DNA全长为1 389 bp,其中,5′非编码区(UTR)为414 bp,3′UTR为279 bp,ORF为696 bp。该基因共编码231个氨基酸。Asnanos1基因在施氏鲟除心脏以外的各组织中均有表达,在雌、雄鱼的鳃、脑、肾、肝脏、脾脏等组织中表达量无显著差异,但在卵巢中的表达量显著高于其他各组织(P0.05)。所得到的结果可为人工培育全雌施氏鲟苗种提供一些基础资料。  相似文献   

西南印度洋真光层海水中固氮细菌多样性     

谢尚微  杨俊毅  张东声  王春生 《海洋学研究》2015,33(3):54-61

本文通过构建克隆文库和基因测序的方法研究了西南印度洋真光层海水中固氮细菌nifH基因的多样性。从构建的2个nifH基因克隆文库中共获得76条有效序列,其中46条来自CTD13-30 m文库,分属10个OTUs;30条来自CTD13-125 m文库,分属8个OTUs。系统发育分析结果显示,研究站位nifH基因序列主要分布于Cluster I和Cluster III两个分支,其中Cluster I中包含蓝细菌和变形菌两个分支,蓝细菌以Group B为优势类群,并未获得束毛藻和Group A的nifH基因序列。此外还有少数nifH基因序列分布于Cluster II。总体来看,西南印度洋固氮生物基因与大西洋的亲缘关系更近;固氮生物的多样性较为丰富,受环境条件的影响,群落结构与其它热带、亚热带寡营养海域具有明显的不同。  相似文献   

客家文化景观基因特征 ——以湖南省炎陵县为例   总被引：1，自引：0，他引：1  

曹帅强  邓运员  杨载田  何清华  李敏 《热带地理》2014,34(6):831-841

以中国南方山丘区具有代表性的客家文化聚居区--炎陵县为例,采用客家文化景观基因的特征提取技术,从民居建筑、传统习俗、地方方言、宗法制度、民间信仰5个角度,提取了炎陵县客家文化景观基因的特征。研究结果表明：1）该县客家人以开放性“围堡式”的血缘宗族聚居模式,与畲、黎、瑶等少数民族通婚繁衍在山丘区的山谷地带;在“入乡随俗”谋求生存发展的环境中,某些方面已适应当地习俗,但仍保留了基本的客家精神及风俗;并以当地炎帝神农文化为主要文化参照,形成了独具炎陵县特色的客家文化。2）该县客家文化的景观基因在不同发生发展过程中有着衣、食、住、行、商等物质性方面的表达载体和地方语言、宗法制度、民间信仰、民情风俗、文化艺术等非物质性方面的表达形式。  相似文献   

3种典型荒漠灌木内生固氮菌及固氮酶基因nifH多样性分析   总被引：1，自引：0，他引：1  

徐正金  罗明  王卫霞  王纯利 《中国沙漠》2014,34(2):472-480

具有特殊生境的内生固氮菌,对改善植物营养、增强植物抗逆性及群落稳定性具有重要作用,是一类潜力巨大、尚待开发的微生物资源。以新疆3种典型荒漠灌木多枝柽柳（Tamarix ramosissima）、黑果枸杞（Lycium ruthenicum）、盐穗木（Halostachys caspica）为材料,从根和枝条组织中分离筛选获得137个内生固氮菌菌株,采用16S rDNA PCR-RFLP、16S rDNA序列测定、BOXAIR-PCR指纹图谱、nifH PCR-RFLP等方法分析其遗传多样性及系统发育关系。结果表明：分离菌株经16SrDNA PCR-RFLP酶切图谱聚类划分为9个遗传类型。序列测定和系统发育分析显示,代表菌株分属于拉恩氏菌属（Rahnella）、假单胞菌属（Pseudomonas）、泛菌属（Pantoea）、芽孢杆菌属（Bacillus）、寡养单胞菌属（Stenotrophomonas）和申氏杆菌属（Shinella）,其中Rahnella为优势种群。一个测定菌株的16SrDNA序列同源性低于97%,提示可能为一个潜在的新种。BOXAIR-PCR分析优势种群的基因组结构特征,获得12种指纹图谱类型,显示出该种群具有丰富的基因组多样性。nifH PCR-RFLP分析分离内生固氮菌菌株固氮酶基因nifH的分子多态性,将其划分为3种基因型,体现了nifH具有高度保守性,同时在不同固氮微生物种群和菌株间也存在一定的多样性。研究结果丰富了固氮微生物物种资源库和基因库,对于内生固氮菌资源的保护和利用奠定了科学基础。  相似文献   

Molecular Cloning of a Cytosolic G6PDH Gene from Populus Suaveolens and Its Expression to Improve the Cold Resistance of Tobacco Plants     

LIN Yuan-zhen  GUO Hai  ZHANG Zhi-yi  LIN Shan-zhi 《冰川冻土》2009,31(6)

Glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) is the first and main regulated enzyme of oxidative pentose phosphate pathway (OPPP), catalyzing the conversion of glucose-6-phosphate to 6-phospho-gluconolactone and playing important roles in the growth and development of plants. It is preciously reported that the enhancement of freezing resistance of Populus suaveolens cuttings is clear related to the distinct increase in cytosolic G6PDH activity. Here, a 1697 bp cDNA fragment (PsG6PDH) is amplified by RT-PCR from cold-induced total RNA of the freezing-tolerant P. suaveolens . A sequence analysis showed that PsG6PDH coding region had 1 530 bp and encoded 510 predicted amino acid residues. Genomic Southern analysis revealed that the isoform is encoded by a few copies of the gene in the poplar genome. The cloned gene PsG6PDH is cloned into binary vector pBI121 and used to transform tobacco. PCR and Southern blotting results verified integration of this gene into the genome of tobacco. Moreover, cold treatment experiments and membrane defense enzyme activity analysis confirmed that overexpression of the PsG6PDH gene could enhance the tolerance to cold or frigid stresses in transgenic plants.  相似文献   

Phylogenetic diversity of planktonic bacteria in the Chukchi Borderland region in summer   总被引：1，自引：1，他引：0  

ZENG Yinxin  YU Yong  LI Huirong  HE Jianfeng  LEE Sang H  SUN Kun 《海洋学报(英文版)》2013,32(6):66-74

Planktonic bacteria are abundant in the Chukchi Borderland region. However, little is known about their diversity and the roles of various bacteria in the ocean. Seawater samples were collected from two stations K2S and K4S where sea ice was melting obviously. The analysis of water samples with fluorescence in situ hybridization (FISH) showed that DMSP-degrading bacteria accounted for 13% of the total bacteria at the station K2S. No aerobic anoxygenic phototrophic (AAP) bacteria were detected in both samples. The bacterial communities were characterized by two 16S rRNA gene clone libraries. Sequences fell into four major lineages of the domain Bacteria, including Proteobacteria (Alpha, Beta and Gamma subclasses), Bacteroidetes, Actinobacteria and Firmicutes. No significant difference was found between the two clone libraries. SAR11 and Rhodobacteraceae clades of Alphaproteobacteria and Pseudoalteromonas of Gammapro-teobacteria constituted three dominant fractions in the clone libraries. A total of 191 heterotrophic bacterial strains were isolated and 76% showed extracellular proteolytic activity. Phylogenetic analysis reveals that the isolates fell into Gammaproteobacteria, Bacteroidetes, Actinobacteria and Firmicutes. The most common genus in both the bacterial isolates and protease-producing bacteria was Pseudoalteromonas. UniFrac data showed suggestive differences in bacterial communities between the Chukchi Borderland and the northern Bering Sea.  相似文献   

凡纳滨对虾P23蛋白基因的筛选、表达和生物信息学分析     

李喜莲  张艳艳  辛静静  钱昭英  刘小林  相建海 《海洋学报》2013,35(4):162-167

克隆凡纳滨对虾极端体重个体的组织差异表达基因P23基因并进行生物信息学分析, 为进一步研究该基因的功能以及凡纳滨对虾的分子选育等研究提供信息。以凡纳滨对虾雌虾极端体重个体腹部肌肉为实验材料, 利用抑制消减杂交(SSH)技术构建极大体重雌性个体和极小体重雌性个体腹部肌肉组织正反向消减cDNA文库:正库(以极大体重个体为试验组, 以极小体重个体为驱动组, L-S)和反库(以极小体重个体为试验组, 以极大体重个体为驱动组, S-L)消减cDNA文库, 并采用实时定量技术分析P23基因的组织表达规律, 利用生物信息学对其功能和结构进行预测。以β-actin为看家基因检测两个文库的消减效率分别为210和25, 实时定量技术分析结果表明P23基因在体重的调节中起上调作用。P23基因编码区序列全长495bp, 编码165个氨基酸, GenBank登录号:JF806619。生物信息学分析发现P23蛋白部分序列含有强疏水性, 无跨膜螺旋结构, 两种信号肽预测都显示P23含有信号肽。  相似文献   

宽体沙鳅(Botia reevesae)β-肌动蛋白基因的cDNA克隆与表达分析     

覃川杰  陈立侨  岳兴建  李二超  王永明  邹远超  谢碧文  齐泽民 《海洋与湖沼》2013,44(2):396-402

利用RT-PCR和快速扩增cDNA末端(rapid amplification of cDNA ends,RACE)技术首次克隆了宽体沙鳅(Botia reevesae)-肌动蛋白基因的cDNA全序列,该序列全长为1795bp,由长100bp的5非翻译区(untranslated region,UTR)、570bp的3非翻译区和1125bp的开放阅读框(open reading frame,ORF)组成,编码375个氨基酸。宽体沙鳅-actin氨基酸序列包含1个糖基化位点、9个N-豆寇酰化位点、3个actin信号位点等主要结构区域。PSI-BLAST比对表明,宽体沙鳅-actin氨基酸与真鲷、罗非鱼、虹鳟等鱼类同源性达99%。NJ法系统进化分析显示宽体沙鳅-actin首先与鲢聚在一起,然后与、尖头等鱼类聚在一起。荧光定量PCR检测-actin基因在宽体沙鳅脑、鳃、心脏、肝、胃等12个组织的表达无显著差异(P<0.05),具有良好的稳定性。  相似文献   

山东部分海域红藻的鉴定与多样性分析     

梁成伟  王娟娟  张晓文  徐东  叶乃好 《海洋科学》2013,37(2):22-29

在山东青岛、威海和烟台近海海域的潮间带进行采样调查,共采取36株红藻样本,对其形态学特征进行了详细的观察.结果显示,所采集的样本在色泽、大小、形态、叶状体形状等外观上均有一定差异,但部分样本间差别并不明显.同时作者采用分子系统学的方法,从藻类样本中分离了rbcL基因片段,并进行了序列分析,利用 rbcL 基因建立了分子系统进化树,对样品间的亲缘关系及多样性进行了系统分析.结果表明,本研究采得的红藻样本有很好的多样性,分别与 GenBank 中已报道的红藻门中的16个属亲缘关系较近.在青岛、烟台和威海3个海域的红藻样本呈现不同的多样性,并且同一属的样品表现出很好的属内种间多样性.  相似文献