水域生境好氧不产氧光合细菌(AAPB)研究进展

好氧不产氧光合细菌（aerobic anoxygenic photosynthesis bacteria,AAPB）是广泛分布于海洋、湖泊及河流等典型水域生境中的异养原核生物,能够以环境中有机物为营养物质来获取细胞生长及代谢所需的能量,同时借助自身独特的菌绿素完成光合作用产能但不合成氧气,在物质循环与能量流动中扮演着重要角色.近年,越来越多的AAPB种属被陆续报道,基于光合基因,例如光合反应中心M亚基（pufM）的分子系统发育分析显示,大部分AAPB属于α-、β-及γ-变形菌,且丰度及多样性随生境的不同而呈现时空地理格局异质性.本文对AAPB的栖息环境与生长特性、丰度与分布、生态功能以及环境驱动因子等方面的研究进展进行了回顾和综述.目前,针对水库生态系统AAPB的研究鲜见报道,作者建议开展水库生境中AAPB多样性分布、环境驱动因素及生态功能研究,丰富对于水生生态系统中功能微生物种群生态结构与代谢功能的认识.     

海洋生物活性肽的功能、制备技术与作用机制研究进展

许多海洋生物活性肽具有降血压、抗炎、抗氧化、抗血栓等多种生物活性,在功能食品及医药领域有着广阔的应用前景。本文主要综述了海洋生物活性肽的制备方法、功能活性及其作用机制,为进一步开发和利用海洋生物活性肽提供参考。     

微藻基因诱变研究及应用进展

微藻是单细胞小型光合生物,是自然界最重要的初级生产者,在食品、能源、医药和环境等行业领域有重要应用。微藻生物技术产业发展所需要的优良微藻株系,除了通过筛选获得外,还可以利用基因诱变或者基因工程等方法获得。利用基因诱变方法获得的突变株,不是转基因作物,且具有更适宜生产需要的优良性状。本文主要综述基因诱变在微藻育种中最新的应用研究进展,为微藻产业化研发工作提供参考。     

厚壳贻贝(Mytilus coruscus)Hox基因家族的鉴定、进化与表达分析

为探究厚壳贻贝Hox基因家族的定位、进化以及在不同成体组织中的表达模式,基于厚壳贻贝全基因组数据,结合生物信息学方法,鉴定分析厚壳贻贝Hox基因家族成员的理化性质、染色体分布、系统进化关系、基因结构以及表达分析。结果显示,从厚壳贻贝全基因组数据中鉴定出11条Hox基因序列,并分别命名为Hox1-5、Antp、Lox2、Lox4、Lox5、Post1、Post2。对11条Hox序列的基本特征分析发现最长的是编码703个氨基酸的Hox2,最短的是编码190个氨基酸Post2,等电点5.11～10.22,且不均等分布于同一条染色体上。亚细胞定位预测结果显示,除Post1基因在细胞质和细胞核中均有发现,其余10个基因亚细胞均定位在细胞核内。系统进化分析发现,使用厚壳贻贝中鉴定出的101条氨基酸序列进行建树,聚类的结果倾向于四类,而从已鉴定的厚壳贻贝11个基因结合软体动物Hox建树结果分析, Post1和Post2聚为一支, Hox4、Antp、Lox5、Lox2和Lox4聚为一个大类,Hox1、Hox2和Hox3各自聚为一类Hox,此外,Hox5单独聚为一类。厚壳贻贝不同组织的qRT-PCR结...     

纤毛虫单细胞基因组DNA微量提取方法的比较及优化

在纤毛虫的分子生物学研究中,单细胞基因组DNA的微量提取是后续基因分析的关键。本研究以海洋纤毛虫红色伪角毛虫为材料,采用直接取完整虫体、裂解法以及3种改良后的试剂盒微量提取DNA方法,分别提取了新鲜样品与4种不同方法保存样品的基因组DNA,比较了9种组合在PCR产物质量、提取所需时间、成本及便捷性方面的优劣,并进一步比较、讨论和探索了4种样品保存方法和5种DNA微量提取方法在纤毛虫单细胞基因组PCR扩增中的可行性。本工作旨在为后续的纤毛虫分子生物学研究提供可资借鉴的技术路线和方法。     

沉积物中氨氧化细菌amoA基因荧光定量PCR检测方法的改进

聚合酶链式反应(Polymerase chain reaction,PCR)较容易受到某些抑制成分的影响,尤其是在对复杂环境样品进行的荧光定量PCR反应中,定量结果的准确性更易受到影响。为减轻这种抑制作用,以采自长江口邻近海域沉积物的DNA为研究对象,采用稀释模板法和添加BSA法对荧光定量PCR反应进行了优化。结果表明2种方法都有减轻抑制的作用,但若考虑方法的准确性和检测的便捷性,则以添加BSA的方法更为优越,最适添加浓度为0.1～0.5μg/μL。这一检测方法的改进,为研究沉积物中微生物在硝化过程中的重要作用提供了可靠的技术途径。     

Wild Barley, Hordeum spontaneum, a Genetic Resource for Crop Improvement in Cold and Arid Regions

Food security in cold and arid regions in the world is threatened by stressful and unpredictable environments.The sus-tainable and economically viable solution for increasing stability of food productivity in cold and arid regions is genetic improvement of crops towards high resistance to abiotic stresses,mainly cold and drought resistance.It is often empha-sized that crop genetic improvement lies in exploiting the gene pools of the wild relatives of the crop plant.Wild barley,H.spontaneum,the progenitor of cultivated barley,is a selfing annual grass of predominantly Mediterranean and Irano-Turanian distribution that penetrates into desert environments where it maintains stable populations.Wild barley is also found in cold regions,such as in Tibet.The adaptation of wild barley to the arid region in Israel and Jordan,and the cold region in Tibet has accumulated rich genetic diversities for drought,salt,and cold resistances in wild barley,which is the genetic resource for barley and other crop improvement in arid and cold regions.These genetic diversities are revealed by allozymes,DNA-based molecular markers,and morphological and physiological traits of wild barley plants.Quantita-tive trait loci(QTLs) related to drought resistance were identified in wild barley via the QTL mapping approach.Drought resistance genes such as dehydrins,hsdr4,and eibi1 were identified in wild barley based on the candidate gene approach,gene differential expression approach,and molecular genetic approach,respectively.Genetics and genomics of wild bar-ley cold resistance have not been exploited yet,remaining a huge treasure for future crop improvement of cold resistance.Advanced backcross QTL analysis,the introgression libraries based on wild barley as donors,a QTL approach based on wide crosses using wild barley,and positional cloning of natural QTLs will play prevailing roles to help us understand the molecular control of cold and drought tolerance.Integration of QTL information into a breeding pipeline aimed at im-proving tolerance t     

电晕电场将大豆Gy3基因导入花棒愈伤组织及植株再生

以花棒幼胚诱导的愈伤组织为受体材料,利用针-板电晕电场将pBI121质粒(含GUS基因和卡那霉素抗性基因)导入花棒愈伤组织,利用组织化学定位实验检测到GUS基因在受体组织中的瞬时表达。用80 mg\5L-1卡那霉素筛选转基因花棒愈伤组织中含有的大豆Gy3基因,获得了38株再生植株,含大豆Gy3基因3株,再生植株经PCR、RT-PCR检测初步证实大豆Gy3基因已转入花棒植物基因组DNA中并发生转录。     

Ancient DNA sequences from Coelodonta antiquitatis in China reveal its divergence and phylogeny

Ancient DNA data have supported a sister relationship between woolly rhinoceros and extant Sumatran rhinoceros.This relationship has been used to explore the divergent times for the woolly rhinoceros from their relatives.Complete and partial ancient DNA sequences of the mitochondrial cytochrome b(cyt b)gene were retrieved from bones of the late Pleistocene Coelodonta antiquitatis excavated from northern and northeastern China.The newly obtained sequences together with the European and northern Asian Coelodonta antiquitatis sequences from GenBank were used to estimate the evolutionary divergence time.Phylogenetic analyses showed the exchange of genetic information between the Chinese individuals and Coelodonta antiquitatis of north Asia,which also indicated a more recent evolutionary timescale(3.8–4.7 Ma)than previous molecular estimations(17.5–22.8 or 21–26 Ma)for woolly rhinoceros based on the fossil calibration of outgroups.This new timescale was more consistent with the fossil record of the earliest known genus Coelodonta.