A report on <Emphasis Type="Italic">Penicillium</Emphasis> in the intramural and extramural air of residential areas of Nagpur city (India)

Prevalence of different species of Penicillium and their concentrations per cubic meter of air were evaluated with the use of Hi-Air sampler system Mark II (Hi-Media Laboratories Ltd., India) in the air of homes (bed-rooms) at four different sites in Nagpur. At each of these sites, air sampling was done fortnightly in triplicate for 2 years duration from June 2000 to May 2002. The sampling was also done in triplicate for the outdoor air in the vicinity of each home on the same day immediately after the indoor sampling was over. The mean concentration of Penicillium colony forming units at four different sites in the indoor air was 32, 46.9, 35 and 35.4 CFU/m³, respectively, whereas in the outdoor air at these same four sites, the mean concentration was 24, 28, 25 and 25.8 CFU/m³ respectively. The Penicillium concentration in the indoor air was found to be higher in winter than in other seasons (ANOVA, p < 0.05). Concentration of Penicillium spp. in intramural environment was always higher than that in extramural environment. Statistically significant difference existed between intramural and extramural environments at all the sites, with maximum difference at a site, which is old crowded area of the city. During the 2-years investigations, 11 species of Penicillium were isolated from the indoor air while nine species were isolated from the air outside the homes. The dominant species of Penicillium in indoor as well as outdoor air were P. citrinum (33.78 and 32.81), P. oxalicum (19.70 and 22.60), and P. chrysogenum (17.64 and 14.50). The percentage of the Penicillium in the indoor air was 10.70 while it was 8.36 in outdoor air. Indoor air showed the presence of P. glaber and P. sclerotiorum, which were absent in the outdoor air.     

Fast classification and compositional analysis of cornstover fractions using Fourier transform near-infrared techniques

The objectives of this research were to determine the variation of chemical composition across botanical fractions of cornstover, and to probe the potential of Fourier transform near-infrared (FT-NIR) techniques in qualitatively classifying separated cornstover fractions and in quantitatively analyzing chemical compositions of cornstover by developing calibration models to predict chemical compositions of cornstover based on FT-NIR spectra. Large variations of cornstover chemical composition for wide calibration ranges, which is required by a reliable calibration model, were achieved by manually separating the cornstover samples into six botanical fractions, and their chemical compositions were determined by conventional wet chemical analyses, which proved that chemical composition varies significantly among different botanical fractions of cornstover. Different botanic fractions, having total saccharide content in descending order, are husk, sheath, pith, rind, leaf, and node. Based on FT-NIR spectra acquired on the biomass, classification by Soft Independent Modeling of Class Analogy (SIMCA) was employed to conduct qualitative classification of cornstover fractions, and partial least square (PLS) regression was used for quantitative chemical composition analysis. SIMCA was successfully demonstrated in classifying botanical fractions of cornstover. The developed PLS model yielded root mean square error of prediction (RMSEP %w/w) of 0.92, 1.03, 0.17, 0.27, 0.21, 1.12, and 0.57 for glucan, xylan, galactan, arabinan, mannan, lignin, and ash, respectively. The results showed the potential of FT-NIR techniques in combination with multivariate analysis to be utilized by biomass feedstock suppliers, bioethanol manufacturers, and bio-power producers in order to better manage bioenergy feedstocks and enhance bioconversion.     

Methylation protects miRNAs and siRNAs from a 3'-end uridylation activity in Arabidopsis

Small RNAs of 21-25 nucleotides (nt), including small interfering RNAs (siRNAs) and microRNAs (miRNAs), act as guide RNAs to silence target-gene expression in a sequence-specific manner. In addition to a Dicer homolog, DCL1, the biogenesis of miRNAs in Arabidopsis requires another protein, HEN1. miRNAs are reduced in abundance and increased in size in hen1 mutants. We found that HEN1 is a miRNA methyltransferase that adds a methyl group to the 3'-most nucleotide of miRNAs, but the role of miRNA methylation was unknown. Here, we show that siRNAs from sense transgenes, hairpin transgenes, and transposons or repeat sequences, as well as a new class of siRNAs known as trans-acting siRNAs, are also methylated in vivo by HEN1. In addition, we show that the size increase of small RNAs in the hen1-1 mutant is due to the addition of one to five U residues to the 3' ends of the small RNAs. Therefore, a novel uridylation activity targets the 3' ends of unmethylated miRNAs and siRNAs in hen1 mutants. We conclude that 3'-end methylation is a common step in miRNA and siRNA metabolism and likely protects the 3' ends of the small RNAs from the uridylation activity.     

Evaluation of oxygen adaptation and identification of functional bacteria composition for anammox consortium in non-woven biological rotating contactor

In this study, the anammox consortium was found to adapt to the wastewater containing dissolved oxygen (DO), as the DO was gradually increased. Batch tests indicated the maximum aerobic ammonium oxidizing activity of the consortium was 1.38mmolNH(4)(+)-N(gVSS)(-1)day(-1), which played key roles in the oxygen consumption process; the maximum anaerobic ammonium oxidizing activity was slightly decreased after long-term oxygen exposure, but only from 21.23mmolNH(4)(+)-N(gVSS)(-1)day(-1) to 20.23mmolNH(4)(+)-N(gVSS)(-1)day(-1). Microbiological community analysis identified two strains similar to Nitrosomonas eutropha were responsible for oxygen consumption, which were able to exist in the autotrophic anaerobic condition for long periods and protect anammox bacteria Planctomycetales from the influence of oxygen. Microbiological composition analysis showed Nitrosomonas and Planctomycetales approximately accounted for 10% and 70% of the bacteria, respectively. The possibility of cultivation anammox consortium in presence of DO will lead to substantial savings of energy and resource in the industrial application.     

小兴安岭大亮子河国家森林公园不同生境下土壤细菌多样性和群落结构

土壤细菌是森林生态系统的一个重要组成成分, 是生态系统中物质循环和能量流动的重要参与者, 细菌群落组成和生物多样性是反映土壤生态功能的重要指标。本文利用高通量测序技术分析了大亮子河国家森林公园内红松(Pinus koraiensis)林、落叶松(Larix gmelinii)林、蒙古栎(Quercus mongolica)林、枫桦(Betula costata)林、针阔混交林、灌木林和草甸等7种不同生境土壤细菌群落组成和多样性的差异性, 探讨该地区土壤细菌群落对不同生境的响应, 为地区森林生态系统的经营管理及生态系统稳定性的维护提供科学理论基础。在门的水平上, 各生境的细菌群落组成基本一致, 其中变形菌门(Proteobacteria)、放线菌门(Actinobacteria)、酸杆菌门(Acidobacteria)和疣微菌门(Verrucomicrobia)在7种生境土壤中相对丰度均大于10.0%, 是细菌中的优势菌门。在属的水平上, 共测得245个菌属, 各样地共有属118个, 占总属数的48.2%, 占总相对丰度的97.8%; 优势菌属分别为Spartobacteria_ genera_incertae_sedis、Gaiella、Gp16、Gp4, 占总相对丰度的47.0%, Spartobacteria_genera_incertae_sedis在7种生境土壤中丰度均最高。7种生境下的土壤细菌多样性和土壤理化因子存在着显著的差异, 红松林的土壤细菌群落多样性和丰富度均高于其他生境。土壤pH是大亮子河森林公园影响土壤细菌多样性的关键因子。     

迟眼蕈蚊抗菌肽BhSGAMP-1-S在大肠杆菌中的优化表达及其活性分析(英文)

【目的】BhSGAMP-1 是迟眼蕈蚊唾液腺抗菌肽,为了能够更好的了解其分子特性,我们将其表达、纯化并进行了活性测定。【方法】依据大肠杆菌稀有密码子设计并合成了抗菌肽基因 BhSGAMP-1-S,以 pMAL-c2X 作为表达载体在大肠杆菌 TB1 中进行融合表达,融合蛋白通过麦芽糖亲和层析柱进行纯化,获得的融合蛋白经肠激酶切割后,混合物通过分子筛凝胶层析和反相高效液相色谱来获得单体重组抗菌肽 BhSGAMP-1-S,对获得的抗菌肽进行活性测定。【结果】在最优的表达条件下融合蛋白以可溶的形式表达,100 mL 诱导菌液经多步纯化后可得 0. 38 mg 的重组抗菌肽 BhSGAMP-1-S,抑菌活性测定表明所获得的抗菌肽对部分测试革兰氏阳性细菌、革兰氏阴性细菌和真菌有较强的抑菌活性。【结论】本研究第一次成功的在大肠杆菌中诱导表达了修饰合成的抗菌肽 BhSGAMP-1-S,纯化后的抗菌肽具有很好的抑菌活性,这为进一步研究和应用奠定了基础。     

Direct competitive chemiluminescence immunoassays based on gold‐coated magnetic particles for detection of chloramphenicol

Direct competitive chemiluminescence immunoassays (CLIA) based on gold‐coated magnetic nanospheres (Au‐MNPs) were developed for rapid analysis of chloramphenicol (CAP). The Au‐MNPs were modified with carboxyl groups and amino groups by 11‐mercaptoundecanoic acid (MUA) and cysteamine respectively, and then were respectively conjugated with CAP base and CAP succinate via an activating reaction using 1‐ethyl‐3‐(3‐dimethylaminopropyl)carbodiimide hydrochloride (EDC) and N‐hydroxysuccinimide (NHS). NSP‐DMAE‐NHS, a new and effective luminescence reagent, was employed to label anti‐CAP antibody (mAb) as a tracer in direct CLIA for CAP detection using a ‘homemade’ luminescent measurement system that was set up with a photomultiplier tube (PMT) and a photon counting unit linked to a computer. The sensitivities and limits of detection (LODs) of the two methods were obtained and compared according to the inhibition curves. The 50% inhibition concentration (IC₅₀) values of the two methods were about 0.044 ng/mL and 0.072 ng/mL respectively and LODs were approximately 0.001 ng/mL and 0.006 ng/mL respectively. To our knowledge, they were much more sensitive than any traditional enzyme‐linked immunosorbent assay (ELISA) ever reported. Moreover, the new luminescence reagent NSP‐DMAE‐NHS is much more sensitive and stable than luminol and its derivatives, contributing to the sensitivity enhancement. Copyright © 2015 John Wiley & Sons, Ltd.     

The functions of Deoxyribonuclease II in immunity and development

Apoptosis, which is usually accompanied by DNA degradation, is important not only for the homeostasis of metazoans but also for mammalian development. If DNA is not properly degraded in these processes, it can cause diverse diseases, such as anemia, cataracts, and some autoimmune diseases. A large effort has been made to identify these nucleases that are responsible for these effects. In contrast to Deoxyribonuclease I (DNase I), Deoxyribonuclease II (DNase II) has been less well characterized in these processes. Additionally, enzymes of DNase II family in Trichinella spiralis, which is an intracellular parasitic nematode, are also considered involved in the development of the nematode. We have compiled information from studies on DNase II from various organisms and found some nonclassic features in these enzymes of T. spiralis. Here we have reviewed the characterization and functions of DNase II in these processes and predicted the functions of these enzymes in T. spiralis during host invasion and development.     

细胞核CaMK和Calcineurin 对大鼠心肌肥厚发生的作用

目的:研究大鼠心肌肥厚时,钙依赖的蛋白激酶和蛋白磷酸酶在心肌细胞膜、细胞浆和细胞核的分布规律,以探讨核钙信号与核反应在心肌肥厚发生过程中的病理生理意义.方法:制备腹主动脉缩窄大鼠心肌肥厚模型,同位素32P掺入法分别测定心肌细胞核、细胞浆和细胞膜的蛋白激酶活性及用无机磷生成显色法测定其蛋白磷酸酶活性.结果:腹主动脉缩窄术后4周大鼠心肌显著肥厚,伴有明显的血液动力学异常.与正常对照组相比较,腹主动脉缩窄心肌肥厚组心肌细胞核钙调素蛋白激酶(CaMK)活性增加101.1%(P＜0.01),其膜的酶活性升高40.2%(P＜0.01),而胞浆的酶活性不变(P＞0.05);心肌细胞核钙调神经磷酸酶(Calcineurin)活性增加43.6%(P＜0.05),膜和胞浆中其活性增加无显著性(P＞0.05).正常组和腹主动脉缩窄心肌肥厚组心肌细胞CaMK和Calcineurin活性分布为核＞膜＞胞浆(P＜0.01).结论:腹主动脉缩窄心肌肥厚时核内钙依赖的CaMK和Calcineurin活性增加,提示压力超负荷时细胞核内钙调节的蛋白磷酸化和去磷酸化水平增高,可能在介导心肌肥厚的发生中起重要作用.     

Genetic structure of <Emphasis Type="Italic">Cerasus jamasakura</Emphasis>, a Japanese flowering cherry,revealed by nuclear SSRs: implications for conservation

The genetic resources of a particular species of flowering cherry, Cerasus jamasakura, have high conservation priority because of its cultural, ecological and economic value in Japan. Therefore, the genetic structures of 12 natural populations of C. jamasakura were assessed using ten nuclear SSR loci. The population differentiation was relatively low (F _ST, 0.043), reflecting long-distance dispersal of seeds by animals and historical human activities. However, a neighbor-joining tree derived from the acquired data, spatial analysis of molecular variance and STRUCTURE analysis revealed that the populations could be divided into two groups: one located on Kyusyu Island and one on Honshu Island. Genetic diversity parameters such as allelic richness and gene diversity were significantly lower in the Kyushu group than the Honshu group. Furthermore, STRUCTURE analysis revealed that the two lineages were admixed in the western part of Honshu Island. Thus, although the phylogeographical structure of the species and hybridization dynamics among related species need to be evaluated in detail using several marker systems, the Kyusyu Island and Honshu Island populations should be considered as different conservation units, and the islands should be regarded as distinct seed transfer zones for C. jamasakura, especially when rapid assessments are required.