利用噬菌体随机肽库筛选抗柯萨奇病毒B3多肽的研究

本实验将柯萨奇病毒B3型(CVB3)大量扩增,应用蔗糖密度梯度离心法纯化病毒。利用噬菌体随机9肽库进行筛选,3轮淘洗后,测定噬菌体克隆抗病毒复制能力。提取阳性克隆DNA并进行测序,推导外源多肽的氨基酸序列。结果表明:3个具有明显抗病毒复制能力的噬菌体阳性克隆被筛选出来,使TCID50由10-7.5SFU/mL分别降至10-5.25、10-6、10-5.5SFU/mL,由此证明可以应用噬菌体肽库来筛选具有抗病毒作用的多肽,本研究为抗病毒多肽制剂的研究奠定了基础。     

呼吸机呼气滤器的研制及防护效果评价

为防止呼吸机呼气管道中的含菌气体扩散污染病房空气,引发交叉感染。利用HEPA材料、活性炭、特殊的缓释杀菌滤材,研制成一套呼吸机呼气除菌过滤装置。经参照有关标准用物理模拟气溶胶颗粒(0.28-0.34um)及微生物气溶胶测试,过滤效率>99.995％,微生物气溶胶滤除率达100％。气流阻力<230Pa,完全能满足临床呼气机的过滤除菌使用条件。     

New contributions to the biodiversity of ciliates (Protozoa,Ciliophora) from Antarctica,including a description of <Emphasis Type="Italic">Gastronauta multistriata</Emphasis> nov. spec.

Antarctica is a remote and isolated biotope which makes it an ideal location for studying new and endemic species. Since there is little literature available on the diversity of ciliates in this area, a taxonomic survey of ciliates from melt-water of Collins glacier, King George Island, was carried out from January to March 2006. As a result, the morphology and infraciliature of five ciliates, including one new species, are described using live observations and silver staining: Gastronauta multistriata nov. spec., Neokeronopsis asiatica Foissner et al., 2010, Paraholosticha muscicola Kahl, 1932, Oxytricha sp., and Cyclidium glaucoma Müller, 1786. Gastronauta multistriata nov. spec. is distinguished from its congeners by the following combination of characters: cell size in vivo on average 80 × 40 μm; 5–9 kineties in left ciliary field; 18–23 kineties in right ciliary field, including 10–12 postoral kineties; 7–10 preoral kineties; dorsal brush along anterior dorsal margin, consisting of 5–8 groups of basal bodies. The only minor differences between the current population of N. asiatica and a previously described Antarctic population are the numbers of caudal cirri (6–10 vs. 8–15) and dorsal kineties (11–13 vs. 12–18). Paraholosticha sterkii is synonymised with P. muscicola. The Antarctic population of C. glaucoma corresponds well with a former population from China, the only difference being the number of kinetids in SK _n (11–17 vs. 9–11). This work will contribute to the understanding of ciliate diversity in this little studied area.     

Detailed regulatory mechanism of the interaction between ZO-1 PDZ2 and connexin43 revealed by MD simulations

The gap junction protein connexin43 (Cx43) binds to the second PDZ domain of Zonula occludens-1 (ZO-1) through its C-terminal tail, mediating the regulation of gap junction plaque size and dynamics. Biochemical study demonstrated that the very C-terminal 12 residues of Cx43 are necessary and sufficient for ZO-1 PDZ2 binding and phosphorylation at residues Ser (-9) and Ser (-10) of the peptide can disrupt the association. However, only a crystal structure of ZO-1 PDZ2 in complex with a shorter 9 aa peptide of connexin43 was solved experimentally. Here, the interactions between ZO-1 PDZ2 and the short, long and phosphorylated Cx43 peptides were studied using molecular dynamics (MD) simulations and free energy calculation. The short peptide bound to PDZ2 exhibits large structural variations, while the extension of three upstream residues stabilizes the peptide conformation and enhanced the interaction. Phosphorylation at Ser(-9) significantly weakens the binding and results in conformational flexibility of the peptide. Glu210 of ZO-1 PDZ2 was found to be a key regulatory point in Cx43 binding and phosphorylation induced dissociation.     

黄孢原毛平革菌抗营养阻遏产漆酶诱变育种及其产酶特性

【目的】筛选能抗营养阻遏产漆酶的黄孢原毛平革菌,论证其产漆酶的确定性及抗营养阻遏产木质素酶的可行性,为白腐菌产酶代谢调控、木质素降解机理的研究奠定基础。【方法】利用重复紫外诱变法,以愈创木酚富氮鉴别培养基筛选目标菌株;比较不同营养条件下菌体生长与产酶动力学差异研究产酶营养调控机理;通过热处理、排除锰离子和加入过氧化氢酶等不同措施论证黄孢原平毛平革菌能否产生漆酶。【结果】3种不同方法均证实选育到的pcR5305和pcR5324菌株在限氮与富氮条件下均能产生漆酶,pcR5305和pcR5324在限氮条件下产漆酶分别达到203.5、187.6 U/L;在富氮条件下为220.6、183.9 U/L,而原菌株pc530在两种条件下都基本不产生漆酶。二菌株产漆酶调控方式不同,pcR5305漆酶产生与菌体生长同步,而pcR5324漆酶产生却受营养氮阻遏。二菌株同时具有抗营养阻遏高产木质素过氧化物酶(LiP)和锰过氧化物酶(MnP)(分别为LiP 1343.2、MnP 252.2 U/L;LiP 1169.5、MnP 172.4 U/L)的能力。【结论】筛选到的黄孢原毛平革菌变异菌株能产漆酶,同时表现了抗营养阻遏产漆酶、木质素过氧化物酶和锰过氧化物酶的能力,具有重要的生产应用与理论研究价值,为白腐菌产酶代谢调控机理研究提供了原始菌株并奠定了良好的基础。     

中国近海牡蛎系统分类研究的现状和对策

探讨了中国近海沿岸牡蛎分类的诸多疑难和热点问题,回顾了国内外包括贝类等动物的分子系统发生学研究的主要进展,分析了中国近海牡蛎系统分类目前存在的问题,重点阐述了利用分子标记等手段解决形态相似种的鉴定和种系发生关系等问题的巨大潜力,报道了利用分子标记进行牡蛎分类研究所取得的最新进展。预期经典分类学和分子系统发生学研究的交叉综合,将大力推动中国近海牡蛎的系统分类和系统发生研究的发展。     

Carbazole and arylamine functionalized iridium complexes for efficient electro-phosphorescent light-emitting diodes

We report the synthesis and characterization of four cyclometalated iridium complexes based on carbazole and arylamine modified 2-phenylpyridine. The carbazole and arylamine groups are linked to 2-phenyl pyridine backbone to enhance the energy harvesting and transfer from host to guest materials. The electrochemical and photophysical properties of the complexes are studied and electroluminescent devices are fabricated. The results show that the complexes with ligands containing carbazole moieties have desirable phosphorescent properties. The device with complex 3 doped PVK (poly (vinylcarbazole)) as emission layer achieves maximum luminous efficiency of 6.56 cd A⁻¹ and maximum brightness of 14448 cd m⁻².     

Phylogenetic analyses of Cornales based on 26S rRNA and combined 26S rDNA-MATK-RBCL sequence data

Nuclear 26S rDNA sequences were used to corroborate and test previously published matK-rbcL-based hypotheses of phylogenetic relationships in Cornales. Sequences were generated for 53 taxa including Alangium, Camptotheca, Cornus, Curtisia, Davidia, Diplopanax, Mastixia, Nyssa, and four families: Grubbiaceae, Hydrangeaceae, Hydrostachyaceae, and Loasaceae. Fifteen taxa from asterids were used as outgroups. The 26S rDNA sequences were initially analyzed separately and then combined with matK-rbcL sequences, using both parsimony and maximum likelihood methods. Eight strongly supported major clades were identified within Cornales by all analyses: Cornus, Alangium, nyssoids (Nyssa, Davidia, and Camptotheca), mastixioids (Mastixia and Diplopanax), Hydrangeaceae, Loasaceae, Grubbia-Curtisia, and Hydrostachys. However, relationships among the major lineages are not strongly supported in either 26S rDNA or combined 26S rDNA-matK-rbcL topologies, except for the sister relationships between Cornus and Alangium and between nyssoids and mastixioids in the tree from combined data. Discrepancies in relationships among major lineages, especially the placement of the long-branched Hydrostachys, were found between parsimony and maximum likelihood trees in all analyses. Incongruence between the 26S rDNA and matK-rbcL data sets was suggested, where Hydrangeaceae was found to be largely responsible for the incongruence. The long branch of Hydrostachys revealed in previous analyses was reduced significantly with more sampling. Maximum likelihood analysis of combined 26S rDNA-matK-rbcL sequences suggested that Hydrostachys might be sister to the remainder of Cornales, that Cornus-Alangium are sisters, that nyssoids-mastixioids are sisters, and that Hydrangeaceae-Loasaceae are sisters, consistent with previous analyses of matK-rbcL sequence data.