水稻籼粳特异性RFLP标记及广亲和品种亲缘关系分析

 应用160个RFLP标记分析了21个水稻广亲和品种6个籼粳测验种，发现其中68个标记可以区分籼粳测验种。21个广亲和品种根据与籼粳测验和共有片段比率的大小 可以分为籼，粳和籼粳中间型三类。68个标记在15个籼粳品种中进一步筛选，得到24个籼粳特异性RFLP标记。它们在亚种内杂交带型相同而亚种产不一样。其中RG358、G318为籼稻专一性探针，在粳稻中表现为零等位。以此24个探针为基础构建了广亲和品品种亲缘关系的树状图。讨论了籼粳特异性RFLP标记在水稻遗传育种实践中的应用。     

海南番木瓜PRSV和PLDMV病毒发生情况及分子鉴定

对海南昌江、乐东、澄迈、文昌和三亚5个主要番木瓜产区的病毒病发生情况进行调查。对76份番木瓜疑似病毒样品进行检测,检测结果表明海南番木瓜病毒病主要有2种：由番木瓜环斑病毒（Papaya ring spot virus,PRSV）引起的番木瓜环斑病毒病和由番木瓜畸形花叶病毒（Papaya leaf-distortion mosaic virus,PLDMV）引起的番木瓜畸形花叶病毒病。其中,番木瓜环斑病毒病最为常见,检出率达77.63％,是影响海南地区番木瓜产业健康发展的主要病毒病;畸形花叶病毒病发生率很低,仅检出2例番木瓜畸形花叶病毒病样品。以PRSV病毒基因组P1和Hc-Pro作为靶标基因进行分子克隆、测序,结果表明海南地区PRSV病毒可明显分为2个株系：HN-PRSV-1株系和HN-PRSV-2株系。此外,基于CP基因的系统进化树分析结果表明在海南新发现的PLDMV病毒可能源于台湾和日本。本研究可为开展番木瓜花叶病的防控和创制抗花叶病毒番木瓜新种质提供数据参考。     

Antibiotic resistance,ESBL genes,integrons, phylogenetic groups and MLVA profiles of Escherichia coli pathotypes isolated from patients with diarrhea and farm animals in south-east of Iran

The aims of this study were to investigate the prevalence, antibiotic resistance, presence of class 1 and 2 integrons, Extended Spectrum β-Lactamases (ESBL) genes, phylogenetic group and epidemiological relationships of EPEC, ETEC and EHEC pathotypes isolated from patients with diarrhea and farm animals in south east region of Iran. A total of 671 diarrheagenic E. coli (DEC) were collected from stool samples of 395 patients with diarrhea and 276 farm cattles and goats. Presence of EPEC, ETEC and EHEC were identified using multiplex-PCR employing primers targeted the shiga toxin (stx), intimin (eae), bundle forming pili (bfp), and enterotoxins (lt and st) genes. The highest proportion of the patients (64%) were children under age 1–15 year (p ≤ 0.05). Among the isolates, atypical EPEC was detected in 26 patients and 14 animal stool samples, while typical EPEC was found in 2 cattles. ETEC isolates were detected in stools of 13 patients and 4 EHEC was identified in 3 goats and one cattle. The isolates were checked for susceptibility to 14 antibiotics. 50% (n = 13) of EPEC and 61.5% (n =8) of ETEC showed multi-drug resistance (MDR) profiles and one EPEC was found to be extensive drug resistant (XDR). In contrast, EHEC isolates were susceptible to the majority of antimicrobial agents. The MDR isolates were positive for bla_TEM and bla_CTX-M ESBL genes and carried class 1 integrons. Further study on the biofilm formation indicated that, 3 out of 4 EHEC isolates showed strong biofilm, while other pathotypes had either moderate, weak or no biofilm activity. Majority of EPEC isolates were belonged to phylogenetic group B1, all except one ETEC were classified as phylogenetic group A and two EHEC were belonged to phylogroup D, respectively. A multilocus variable tandem repeat analysis (MLVA) exhibited 22 distinct patterns. In conclusion, MLVA data showed high clonal diversity. Presence of EHEC in animal origins pose public health concern in this region.     

The first detection of influenza in the Finnish pig population: a retrospective study

Background

Swine influenza is an infectious acute respiratory disease of pigs caused by influenza A virus. We investigated the time of entry of swine influenza into the Finnish pig population. We also describe the molecular detection of two types of influenza A (H1N1) viruses in porcine samples submitted in 2009 and 2010.This retrospective study was based on three categories of samples: blood samples collected for disease monitoring from pigs at major slaughterhouses from 2007 to 2009; blood samples from pigs in farms with a special health status taken in 2008 and 2009; and diagnostic blood samples from pigs in farms with clinical signs of respiratory disease in 2008 and 2009. The blood samples were tested for influenza A antibodies with an antibody ELISA. Positive samples were further analyzed for H1N1, H3N2, and H1N2 antibodies with a hemagglutination inhibition test. Diagnostic samples for virus detection were subjected to influenza A M-gene-specific real-time RT-PCR and to pandemic influenza A H1N1-specific real-time RT-PCR. Positive samples were further analyzed with RT-PCRs designed for this purpose, and the PCR products were sequenced and sequences analyzed phylogenetically.

Results

In the blood samples from pigs in special health class farms producing replacement animals and in diagnostic blood samples, the first serologically positive samples originated from the period July–August 2008. In samples collected for disease monitoring, < 0.1%, 0% and 16% were positive for antibodies against influenza A H1N1 in the HI test in 2007, 2008, and 2009, respectively. Swine influenza A virus of avian-like H1N1 was first detected in diagnostic samples in February 2009. In 2009 and 2010, the avian-like H1N1 virus was detected on 12 and two farms, respectively. The pandemic H1N1 virus (A(H1N1)pdm09) was detected on one pig farm in 2009 and on two farms in 2010.

Conclusions

Based on our study, swine influenza of avian-like H1N1 virus was introduced into the Finnish pig population in 2008 and A(H1N1)pdm09 virus in 2009. The source of avian-like H1N1 infection could not be determined. Cases of pandemic H1N1 in pigs coincided with the period when the A(H1N1)pdm09 virus was spread in humans in Finland.     

利用ITS核酸序列分析鉴定海洋青霉菌

[目的]利用ITS核酸序列对6株根据形态学特征初步鉴定为青霉菌的海洋真菌进行鉴定。[方法]采用分子生物学技术,对6株样品的ITS序列进行克隆,并利用ClustalX1．83软件对结果进行系统发育分析。[结果]通过PCR克隆获得了6株样品的ITS序列,将结果与GenBank中已登陆的其他序列进行系统发育分析,确定了6株菌株均属于青霉菌属。[结论]该6株菌株均属于青霉菌属。     

昆虫一氧化氮合酶基因研究进展及其同源分析

概述了果蝇、家蚕、长红猎蝽、按蚊和烟草角蛾一氧化氮合酶的生理作用、生化特性、研究方法、基因克隆等方面的研究进展,并采用生物信息学方法比较了5种昆虫NOS的同源性,构建了进化树.     

新疆小家鼠控制区序列分析

[目的]研究新疆地区小家鼠控制区的序列多样性。[方法]对14只来自新疆于田、和丰和乌鲁木齐的小家鼠个体进行基因组DNA提取,控制区PCR扩增和序列测定,并分析其遗传多样性,构建系统进化树。[结果]14只小家鼠基因组大小均在20000bp以上;小家鼠控制区序列中A、T、G、C的平均含量分别为：T：29．0％;C：25．2％;A：33．9％;G：11．9％,个体间碱基组成几乎无差别;14只小家鼠个体与M.m.musculus的亲缘关系较近,在系统进化树中共享1个分支,且该分支中2225、2228和2226具有相同的支长,2242和2243具有相同的支长,2249、2247和2251具有相同的支长。[结论]供试14只新疆小家鼠个体属于M.m.musculus亚种。     

樱桃谷鸭线粒体控制区的遗传多样性分析

[目的]探究樱桃谷鸭的遗传背景。[方法]通过线粒体D—loop区测序对樱桃谷鸭19个个体进行测序。[结果]结果表明,樱桃谷鸭群体内的核苷酸多样性（Pi）、单倍型多样度（Hd）和平均核苷酸差异数（K）分别为0．01434、0．982和10．140,存在4种单倍型,可以将樱桃谷鸭分为2个较大的类群,同时樱桃谷鸭与绿头野鸭、建昌鸭和野生斑嘴鸭有较高的亲缘性。鸭种群线粒体D—loop区序列个体变异程度很小,但种群的遗传多样性水平很高,可用于群体内及群体间不同个体的遗传多样性分析。[结论]该研究结果为樱桃谷鸭的多态性位点和单倍型的深入分析提供参考。     

中国4个牛种MSTN基因外显子2多态性分析与其系统发生关系研究

[目的]解决牛亚科动物近缘物种的分类归属问题,了解牛亚科各种群遗传多样性。[方法]采用酚-氯仿抽提法从4个中国牛种中提取基因组DNA,对MSTN基因进行PCR扩增和测序,构建系统发育树,探讨4个牛种间MSTN基因外显子2的系统发生关系。[结果]MSTN基因外显子2编码区为372 bp。蒙古牛、牦牛和独龙牛的MSTN基因外显子2具有丰富的多态性。在所测66个样本中存在3个核苷酸多态位点,定义了6种单倍型。雷琼牛、蒙古牛、独龙牛与巴州牦牛享有共同的单倍型。巴州牦牛独自聚成一支,而雷琼牛与一部分独龙牛、大部分蒙古牛和引用瘤牛聚成一支。[结论]蒙古牛、雷琼牛、独龙牛种间存在着基因交流。牦牛与普通牛、瘤牛的分化较明显,比瘤牛与普通牛的亲缘关系要远。     

厌氧除磷菌的富集及功能菌组成研究

[目的]富集厌氧除磷菌,并对功能菌的组成进行研究。[方法]利用厌氧连续流反应器,以养殖场新鲜鸡粪为种泥,控制和保持反应器内ORP为-337～-230 mV,pH 6～7,温度30～35℃,富集厌氧除磷功能菌。跟踪监测反应器进出水的总磷（TP）、磷酸盐（PO43--P）和氨氮（NH2-N）去除率。当TP的去除率达到60.89%时,取样进行PCR-DGGE分析,用MEGA 4.0软件构建系统进化树。[结果]鸡粪在反应器中连续培养140 d后,TP的去除率平均达到39.86%,大大高于文献报道的24.19%,PO43--P去除率平均达到40.82%,NH3-N的去除率平均达到34.39%;NH3-N与TP的去除率之间存在一定的相关性,厌氧条件下可达到同时脱氮（去除氨氮）除磷（还原磷酸生成磷化氢）的效果;通过对样品的PCR-DGGE分析和进化树分析,获得一种具发酵功能的乳球菌属（Lactoccus）和一种具有发酵、固氮和厌氧除磷功能的梭菌属（Clostridium）。[结论]该研究可为厌氧除磷机理提供理论依据。