Diverse molecular compositions of dissolved organic matter derived from different composts using ESI FT-ICR MS

Dissolved organic matter (DOM) derived from various composts can promote significant changes of soil properties. However, little is known about the DOM compositions and their similarities and differences at the molecular level. In this study, the molecular compositions of DOM derived from kitchen waste compost (KWC), green waste compost (GWC), manure waste compost (MWC), and sewage sludge compost (SSC) were characterized by electrospray ionization coupled with Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS). The molecular formulas were classified into four subcategories: CHO, CHON, CHOS, and CHONS. The KWC, MWC, and SSC DOM represented the highest fraction (35.8%-47.4%) of CHON subcategory, while the GWC DOM represented the highest fraction (68.4%) of CHO subcategory. The GWC DOM was recognized as the nitrogen- and sulfur-deficient compounds that were less saturated, more aromatic, and more oxidized compared with other samples. Further analysis of the oxygen, nitrogen-containing (N-containing), and sulfur-containing (S-containing) functional groups in the four subcategories revealed higher organic molecular complexity. Comparison of the similarities and differences of the four samples revealed 22.8% ubiquitous formulas and 17.4%, 11.1%, 10.7%, and 6.3% unique formulas of GWC, KWC, SSC, and MWC DOM, respectively, suggesting a large proportion of ubiquitous DOM as well as unique, source-specific molecular signatures. The findings presented herein provide new insight into the molecular characterization of DOM derived from various composts and demonstrated the potential role of these different compounds for agricultural utilization.     

重金属复合污染对蚕豆性状影响的模糊聚类与性状代间分化的摄动分析

运用正交设计，经过４代的原位种植实验，获得了Ｐｂ＾２＋、Ｃｄ＾２＋、Ｈｇ＾２＋、Ｚｎ＾２＋复合污染对同一蚕豆种质在株高、首次开花时间、每株结豆荚数、单位豆荚豆粒数（每２０个豆荚）、种子的重量（５０粒）等数量性状的表型数据。利用模糊聚类和摄动分析方法，获得了２５种污染组合对蚕豆数量性状影响的聚类特征，考察了蚕豆代间分化的趋向。实验结果表明，重金属复合污染对蚕豆的毒害作用，不仅同元素的种类和各自的浓度     

Improved direct molecular diagnosis and rapid fetal sexing

Adaptations of the techniques of modern molecular biology to prenatal diagnosis has opened new avenues for the detection of genetic diseases. We have taken advantage of the rapid adhesion of colony forming cells in cultured amniotic fluid samples to develop an improved method for molecular diagnosis. By employing the cell adherence regime sickle cell diagnosis using Mst II can be undertaken directly. In addition, hybridization with a cloned repetitive sequence that is of Y origin and has limited autosomal homology permits rapid fetal sexing in 3 to 4 days without compromising conventional cytogenetic or biochemical analysis. This combination of techniques provides a useful adjunct to convential prenatal genetic diagnosis in the second trimester.     

糖蜜酒精蒸馏废液色素研究

采用凝胶渗透色谱方法测定从甘蔗糖蜜酒精废液中提纯的色素的分子量。通过吸收光谱、原子吸收光谱、氨基酸分析、溶剂析出等方法，确定色素的成分。结果表明，该色素具有三个不同分子量的组分，重均分子量分别为21889、987和439Da。主要有酚类色素、焦糖色素和美拉德色素等3种色素，其质量分数分别为20%、67.7%和12.3%。色素中铁质量分数为0.12%，水解氨基酸质量分数为5.23%。     

Holographic QSAR of selected esters

The HQSAR (Holographic QSAR) method, which has been recently developed, can offer the ability to rapidly and easily generate QSAR models of high statistical quality and predictive value. HQSAR analysis requires selecting values for parameters that specify the size of the hologram that is to be used, and the size and type of fragment substructures that are to be encoded. The color coding is provided by HQSAR to reflect which molecular fragments may be important contributors to the biological activity. In this work, we studied the quantitative structure activity relationship of selected esters using the HQSAR method. A robust HQSAR model with r² (non-cross-validated regression coefficient) of 0.981 and q² (cross-validated regression coefficient) of 0.912, was developed after optimizing the fragment size and the hologram length. The color coding analysis, which has rarely been reported before, was done here to explain the outlier successfully.     

环境微生态研究中的分子生物学新技术

随着分子生物学的发展,可用于环境微生态研究的新方法新手段不断出现.利用这些分子生物学技术,可直接对环境样品的总DNA进行分析,绕开菌株分离和培养瓶颈,可以最大限度地获得相关微生物的遗传信息,全面地分析环境中微生物的多样性.对目前广泛应用于环境微生态研究的分子生物学新技术,包括rDNA基因序列分析、变性梯度凝胶电泳、温度梯度凝胶电泳、单链构象多态性、限制性片段长度多态性、随机扩增多态性DNA、核酸杂交和DNA芯片等技术进行了综述.     

一种新去整合素Adinbitor的表达、序列分析及其对C6神经胶质瘤细胞凋亡的诱导

Adinbitor为一通过基因工程方法获得的来自于中国白眉蝮蛇毒腺的去整合素家族的新成员 .从蝮蛇毒腺中提取总RNA进行RT -PCR扩增 ,获得了 2 19bp的白眉蝮蛇去整合素基因 .cDNA测序及由此推导的氨基酸序列结果显示 ,Adinbitor为含有 73个氨基酸的多肽 ,其中包括 12个半胱氨酸 ,并具有去整合素的特征模序 -RGD .对此去整合素基因进行克隆、转化与诱导后 ,得到了该蛋白的可溶性高效表达 .经组氨酸亲和层析纯化 ,获得了分子量Mr为 9×10 3 的均质融合蛋白 ,并将其命名为adinbitor.序列分析表明 ,adinbitor与已发表于GENBANK上的整合素序列有很高的同源性 ,其中同源性最高的是南韩的saxatilin ,二者的蛋白质同源性高达 91.78% .活性测定结果表明 ,Adinbitor能有效地诱导神经胶质瘤细胞C6的细胞凋亡 ,有希望成为一种抗癌新药 .图 5参 15     

Fertility signals in the bumblebee Bombus terrestris (Hymenoptera: Apidae)

In eusocial Hymenoptera, queen control over workers is probably inseparable from the mechanism of queen recognition. In primitively eusocial bumblebees (Bombus), worker reproduction is controlled not only by the presence or absence of a dominant queen but also by other dominant workers. Furthermore, it was shown that the queen dominance is maintained by pheromonal cues. We investigated whether there is a similar odor signal released by egg-laying queens and workers that may have a function as a fertility signal. We collected cuticular surface extracts from nest-searching and breeding Bombus terrestris queens and workers that were characterized by their ovarian stages. In chemical analyses, we identified 61 compounds consisting of aldehydes, alkanes, alkenes, and fatty acid esters. Nest-searching queens and all groups of breeding females differed significantly in their odor bouquets. Furthermore, workers before the competition point (time point of colony development where workers start to develop ovaries and lay eggs) differed largely from queens and all other groups of workers. Breeding queens showed a unique bouquet of chemical compounds and certain queen-specific compounds, and the differences toward workers decrease with an increasing development of the workers' ovaries, hinting the presence of a reliable fertility signal. Among the worker groups, the smallest differences were found after the competition point. Egg-laying females contained higher total amounts of chemical compounds and of relative proportions of wax-type esters and aldehydes than nest-searching queens and workers before the competition point. Therefore, these compounds may have a function as a fertility signal present in queens and workers.     

Inhibition of thrombin by functionalized C60 nanoparticles revealed via in vitro assays and in silico studies

The studies on the human toxicity of nanoparticles (NPs) are far behind the rapid development of engineered functionalized NPs. Fullerene has been widely used as drug carrier skeleton due to its reported low risk. However, different from other kinds of NPs, fullerene-based NPs (C₆₀ NPs) have been found to have an anticoagulation effect, although the potential target is still unknown. In the study, both experimental and computational methods were adopted to gain mechanistic insight into the modulation of thrombin activity by nine kinds of C₆₀ NPs with diverse surface chemistry properties. In vitro enzyme activity assays showed that all tested surface-modified C₆₀ NPs exhibited thrombin inhibition ability. Kinetic studies coupled with competitive testing using 3 known inhibitors indicated that six of the C₆₀ NPs, of greater hydrophobicity and hydrogen bond (HB) donor acidity or acceptor basicity, acted as competitive inhibitors of thrombin by directly interacting with the active site of thrombin. A simple quantitative nanostructure-activity relationship model relating the surface substituent properties to the inhibition potential was then established for the six competitive inhibitors. Molecular docking analysis revealed that the intermolecular HB interactions were important for the specific binding of C₆₀ NPs to the active site canyon, while the additional stability provided by the surface groups through van der Waals interaction also play a key role in the thrombin binding affinity of the NPs. Our results suggest that thrombin is a possible target of the surface-functionalized C₆₀ NPs relevant to their anticoagulation effect.     

New molecular method to detect denitrifying anaerobic methane oxidation bacteria from different environmental niches

The denitrifying anaerobic methane oxidation is an ecologically important process for reducing the potential methane emission into the atmosphere. The responsible bacterium for this process was Candidatus Methylomirabilis oxyfera belonging to the bacterial phylum of NC10. In this study, a new pair of primers targeting all the five groups of NC10 bacteria was designed to amplify NC10 bacteria from different environmental niches. The results showed that the group A was the dominant NC10 phylum bacteria from the sludges and food waste digestate while in paddy soil samples, group A and group B had nearly the same proportion. Our results also indicated that NC10 bacteria could exist in a high pH environment (pH 9.24) from the food waste treatment facility. The Pearson relationship analysis showed that the pH had a significant positive relationship with the NC10 bacterial diversity (p < 0.05). The redundancy analysis further revealed that the pH, volatile solid and nitrite nitrogen were the most important factors in shaping the NC10 bacterial structure (p = 0.01) based on the variation inflation factors selection and Monte Carlo test (999 times). Results of this study extended the existing molecular tools for studying the NC10 bacterial community structures and provided new information on the ecological distributions of NC10 bacteria.