Common evolutionary origin of aquareoviruses and orthoreoviruses revealed by genome characterization of Golden shiner reovirus, Grass carp reovirus, Striped bass reovirus and golden ide reovirus (genus Aquareovirus, family Reoviridae)

Full-length and partial genome sequences of four members of the genus Aquareovirus, family Reoviridae (Golden shiner reovirus, Grass carp reovirus, Striped bass reovirus and golden ide reovirus) were characterized. Based on sequence comparison, the unclassified Grass carp reovirus was shown to be a member of the species Aquareovirus C The status of golden ide reovirus, another unclassified aquareovirus, was also examined. Sequence analysis showed that it did not belong to the species Aquareovirus A or C, but assessment of its relationship to the species Aquareovirus B, D, E and F was hampered by the absence of genetic data from these species. In agreement with previous reports of ultrastructural resemblance between aquareoviruses and orthoreoviruses, genetic analysis revealed homology in the genes of the two groups. This homology concerned eight of the 11 segments of the aquareovirus genome (amino acid identity 17-42%), and similar genetic organization was observed in two other segments. The conserved terminal sequences in the genomes of members of the two groups were also similar. These data are undoubtedly an indication of the common evolutionary origin of these viruses. This clear genetic relatedness between members of distinct genera is unique within the family Reoviridae. Such a genetic relationship is usually observed between members of a single genus. However, the current taxonomic classification of aquareoviruses and orthoreoviruses in two different genera is supported by a number of characteristics, including their distinct G+C contents, unequal numbers of genome segments, absence of an antigenic relationship, different cytopathic effects and specific econiches.

天然产物中的HIV-1 非核苷类逆转录酶抑制剂

综述了天然产物中对H IV 21 逆转录酶具有抑制活性的化合物的来源和分类。重点介绍了几种H IV 21 非核 苷类逆转录酶抑制剂(NNRT Is) 的性质、特点、抗H IV 21 活性及其构效关系。从天然资源和传统中草药发现具有新 结构、新作用机制的天然NNRT Is 是开发研制抗H IV 21 药物的一条极有希望的途径。

Photonic crystal point-shift nanolaser with ultimate small modal volume

A photonic crystal nanolaser consisting of only the shift of two lattice points was fabricated by HJ/Xe inductively coupled plasma etching. The room temperature lasing was observed by photopumping. The three-dimensional finite-difference time-domain calculation showed that the lasing mode has small modal volume close to (lambda/2n)(3).

VG-quattro四极质谱仪计算机硬盘机的升级

对VG-quattro四极质谱仪计算机的硬盘机进行了升级改造,用IDE接口取代了原ST506/412接口,从而可以安装3.5英寸420MB硬盘。介绍了IDE接口,IDE接口卡的配置,硬盘类型参数的设置及硬盘的逻辑安装。