新疆饼干衣属地衣分类学研究

该研究以采自新疆的100余份饼干衣属(Rinodina)地衣标本为研究材料,通过形态解剖特征观察、地衣化学成分分析以及分子生物学鉴定方法鉴定出9个种,包括2个中国新记录种——阿富汗饼干衣(Rinodina afghanica)和古氏饼干衣(Rinodina guzzinii),7个常见种分别是：包氏饼干衣(R. bohlinii)、毕氏饼干衣(R. bischoffii)、代谢饼干衣(R. metaboliza)、密果饼干衣(R. pycnocarpa)、特雷氏饼干衣(R. trevisanii)、甘肃饼干衣(R. straussii)和地生饼干衣(R. terrestris)。并提供了新疆饼干衣属地衣的分种检索表、每个物种的详细描述、新记录种的特征图片以及系统发育分析。     

Testing DNA barcodes in closely related species of Curcuma (Zingiberaceae) from Myanmar and China

The genus Curcuma L. is commonly used as spices, medicines, dyes and ornamentals. Owing to its economic significance and lack of clear‐cut morphological differences between species, this genus is an ideal case for developing DNA barcodes. In this study, four chloroplast DNA regions (matK, rbcL, trnH‐psbA and trnL‐F) and one nuclear region (ITS2) were generated for 44 Curcuma species and five species from closely related genera, represented by 96 samples. PCR amplification success rate, intra‐ and inter‐specific genetic distance variation and the correct identification percentage were taken into account to assess candidate barcode regions. PCR and sequence success rate were high in matK (89.7%), rbcL (100%), trnH‐psbA (100%), trnL‐F (95.7%) and ITS2 (82.6%) regions. The results further showed that four candidate chloroplast barcoding regions (matK, rbcL, trnH‐psbA and trnL‐F) yield no barcode gaps, indicating that the genus Curcuma represents a challenging group for DNA barcoding. The ITS2 region presented large interspecific variation and provided the highest correct identification rates (46.7%) based on BLASTClust method among the five regions. However, the ITS2 only provided 7.9% based on NJ tree method. An increase in discriminatory power needs the development of more variable markers.     

Measures of human olfactory perception during pregnancy

Although considerable anecdotal evidence suggests that pregnancy affects olfactory sensitivity, scientific evidence is limited and inconclusive. Whereas hedonic ratings are affected by pregnancy, odor identification is not. The aim of the current study was to examine odor perception in women across pregnancy and in the postpartum period. One hundred nonsmoking women who were pregnant, postpartum, or had never been pregnant were tested on the University of Pennsylvania Smell Identification Test (UPSIT). Intensity ratings and scratch patterns were collected as potential indicators of sensitivity, and participants rated the odors' pleasantness. Participants also rated their own sense of smell. Mean UPSIT scores did not differ significantly across groups indicating no difference in odor identification. Trends in planned comparisons suggested that in the first trimester, odors were rated as more intense and less pleasant. In the first trimester, women scratched the odor strips significantly fewer times. Consistent with previous reports, 90% of pregnant women reported that specific odors smelled less pleasant and 60% reported that some odors smelled more pleasant. Although nearly two-thirds of pregnant women rated their olfactory sensitivity to be enhanced during pregnancy and overall pregnant women's self-rated olfactory sensitivity was higher than controls', self-ratings were not correlated with UPSIT scores nor odor intensity ratings. These results suggest that these and previous findings may reflect the fact that the effect of pregnancy on olfaction is small and inconsistent.     

Allosteric sites can be identified based on the residue–residue interaction energy difference

Allosteric drugs act at a distance to regulate protein functions. They have several advantages over conventional orthosteric drugs, including diverse regulation types and fewer side effects. However, the rational design of allosteric ligands remains a challenge, especially when it comes to the identification allosteric binding sites. As the binding of allosteric ligands may induce changes in the pattern of residue–residue interactions, we calculated the residue–residue interaction energies within the allosteric site based on the molecular mechanics generalized Born surface area energy decomposition scheme. Using a dataset of 17 allosteric proteins with structural data for both the apo and the ligand‐bound state available, we used conformational ensembles generated by molecular dynamics simulations to compute the differences in the residue–residue interaction energies in known allosteric sites from both states. For all the known sites, distinct interaction energy differences (>25%) were observed. We then used CAVITY, a binding site detection program to identify novel putative allosteric sites in the same proteins. This yielded a total of 31 “druggable binding sites,” of which 21 exhibited >25% difference in residue interaction energies, and were hence predicted as novel allosteric sites. Three of the predicted allosteric sites were supported by recent experimental studies. All the predicted sites may serve as novel allosteric sites for allosteric ligand design. Our study provides a computational method for identifying novel allosteric sites for allosteric drug design. Proteins 2015; 83:1375–1384. © 2014 Wiley Periodicals, Inc.     

米曲霉耐热木聚糖酶纯化及酶学特性研究

对米曲霉原始发酵液中耐热木聚糖酶进行纯化和酶学特性研究,利用甘蔗渣为碳源培养米曲霉,通过超滤和阴离子交换柱两步纯化得到木聚糖酶XynH1,分子量35．402kDa,利用飞行时间质谱和SDS—PAGE分析,推断XynH1为XylanaseXynF1,分子量为35．402kDa。XynH1属于糖苷水解酶家族10,酶活为442．2IU／nag,最适pH和温度分别为pH6．0和65℃,80℃以下及pH4．0～10．5范围内较稳定。     

自动识别技术在昆虫分类鉴别研究中的应用

昆虫的自动识别是重要的新兴研究领域,它以直接、快速、方便等优点日益受到人们的青睐。昆虫是世界上最大的生物类群,鉴定工作费时耗力,然而分类专家又在逐渐减少。近年来,昆虫自动识别技术的发展为解决这一矛盾提供了乐观的方案。众多分类学家不断探索自动识别的方法和理论,并开发出了一批识别软件。本文介绍自动识别的原理,分类讨论自动识别的技术和方法,并分析提出面临的困难和应对策略。     

鹊肾树树皮的化学成分和抗炎作用研究

通过药理实验确定了鹊肾树树皮的乙酸乙酯萃取物为抗炎活性部位,并利用色谱技术从该部位中分离得到了7个化合物,通过UV、IR、NMR、MS等现代谱学方法鉴定化合物的结构分别为:丁二酸(1)、6-乙基-5-羟基-2,7-二甲氧基-1,4-萘醌(2)、3β,20-二羟基-5β-孕甾烷(3)、5-羟基麦芽酚(4)、双[5-甲酰基...     

黄瑞木果实红色素的分离及其化学结构研究

采用纸层析、紫外-可见光谱、红外光谱和液-质联用等技术对福建野生黄瑞木〔Adinandra millettii(Hook. et Arn.)Benth.〕果实红色素进行了分析研究。结果表明,该红色素主要含有矢车菊素-3-芸香糖苷(cyanidin-3-rutinoside)和矢车菊素-3-葡萄糖苷(cyanidin-3-glucoside)2种花色苷,呈鲜艳的红色,可作为天然保健食品的色素添加剂加以推广应用。     

羊蹄甲属植物种子的裂解色谱鉴定法研究

本文探索了裂解气相色谱法作为植物种子分类表征方法的可能性。对豆科植物中不同属、不同亚属及相同亚属的共10种种子的裂解色谱图,用分区编码法进行区别,分析结果表明,不同种子最少有一个编码不同,方法简易快速,可为高等植物种子的区分提供一种佐证手段。     

一株鸭源传染性支气管炎病毒的分离鉴定及结构蛋白基因和血清型分析

【目的】对从广西某鸭场发生呼吸道感染的11天龄樱桃谷肉鸭分离到的病毒株进行鉴定,并探索此鸭源病毒分离株的遗传变异情况。【方法】通过血凝试验、鸡胚接种实验、3?端非编码区(3'UTR)基因扩增与序列测定对分离株进行鉴定,并对该分离株的结构基因S1、E、M和N分别进行序列测定以及相似性、系统进化树分析和血清型鉴定。【结果】血凝试验为阴性,接种鸡胚盲传5代后出现侏儒胚,3?UTR基因测序结果表明为传染性支气管炎病毒(IBV)序列。该分离株S蛋白的裂解位点为RRSRR,S1、E、M和N基因与IBV毒株H120、4/91、LTD3核苷酸相似性分别为:78.6%–99.7%、85.4%–100.0%、91.6%–93.2%、86.7%–91.7%。除N基因存在点突变外,S1、E和M基因均存在氨基酸的突变、插入和(或)缺失。系统进化树分析显示,其S1基因属于4/91型,E、M和N基因均为LDT3型。血清型分析表明,该分离株的血清型不同于疫苗株H120和4/91。【结论】此鸭源病毒分离株为IBV,且该分离株的基因型与血清型均发生了变异。本研究结果暗示禽类传染性支气管炎的防控面临着更严峻的挑战。