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Detection of presumed genes encoding beta-lactamases by sequence based screening of metagenomes derived from Antarctic microbial mats

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Frontiers of Environmental Science & Engineering 2019年第3期13卷 173-184页

作者： Gaston Azziz matias Gimenez Hector Romero Patricia m. Valdespino-Castillo Luisa I. Falcon Lucas A. m. Ruberto Walter P. mac Cormack Silvia batista molecular microbiology Unit Clemente Estable Biological Research Insitute Montevideo 11600 Uruguay microbiology Laboratory Faculty of Agronomy UdelaR Montevideo 12900 Uruguay Genome Organization and Evolution Laboratory Ecology and Evolution Department Faculty of Sciences UdelaR Montevideo 11400 Uruguay molecular biophysics and Integrated bioimaging BSISB Imaging Program Lawrence Berkeley National Laboratory Berkeley CA 94720 USA bacteial Ecology Laboratory Ecology Institute National Autonomous University of Mexico CDMX 04510 Mexico UN Am Yucatan Technology and Science Park Merida 97302 Mexico Argentine Antarctic Institute Buenos Aires 1650 Argentina biotechnology Unit Faculty of Pharmacy and Biochemistry Nanobiotec Institute UBA-CONICET Buenos Aires 1113 Argentina

Analysis of environmental samples for bacterial antibiotic resistance genes may have different objectives and analysis strategies. In some cases, the purpose was to study diversity and evolution of genes that could be grouped within a mechanism of antibiotic resistance. Different protocols have been designed for detection and confirmation that a functional gene was found. In this study, we present a sequence-based screening of candidate genes encoding beta-lactamases in 14 metagenomes of Antarctic microbial mats. The samples were obtained from different sites, representing diverse biogeographic regions of maritime and continental Antarctica. A protocol was designed based on generation of Hidden markov models from the four beta-lactamase classes by Ambler classification, using sequences from the Comprehensive Antibiotic Resistance Database (CARD). The models were used as queries for metagenome analysis and recovered contigs were subsequently annotated using RAST. According to our analysis, 14 metagenomes analyzed contain A, b and C beta-lactamase genes. Class D genes, however, were identified in 11 metagenomes. The most abundant was class C (46.8%), followed by classes b (35.5%), A (14.2%) and D (3.5%). A considerable number of sequences formed clusters which included, in some cases, contigs from different metagenomes. These assemblies are clearly separated from reference clusters, previously identified using CARD beta-lactamase sequences. While bacterial antibiotic resistance is a major challenge of public health worldwide, our results suggest that environmental diversity of beta-lactamase genes is higher than that currently reported, although this should be complemented with gene function analysis.

关键词： beta-lactamases Antibiotic resistance coding genes metagenomes Antarctic microbial mats

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Geochemistry of the Rare Earth Elements (REE) Distribution in Terengganu Coastal Waters: A Study Case from Redang Island marine Sediment

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Open Journal of marine Science 2013年第3期3卷 154-159页

作者： A. Nor Antonina N. A. m. Shazili b. Y. Kamaruzzaman m. C. Ong Y. Rosnan F. N. Sharifah Department of marine Science Faculty of Maritime Studies and Marine Science University Malaysia Terengganu Kuala Terengganu Malaysia Department of marine Science Faculty of Maritime Studies and Marine Science University Malaysia TerengganuKuala Terengganu Malaysia Institute of Oceanography and maritime Studies Kulliyyah of Science International Islamic University MalaysiaKuantan Malaysia

A study on the rare earth elements (REEs) of Redang Island marine sediments was conducted in August 2011 during the premonsoon season. bottom sediments were collected from 27 sampling stations on board UmT Discovery II vessel using a Smith mcIntyre grab and analyzed for rare earth elements (REEs) using inductively coupled plasma mass spectrometry (ICP-mS). Results showed that the REEs patterns in sediments reflected the source rock patterns with an overall order of abundance such as: light rare earth elements (LREE) > middle rare earth element (mREE) > high rare earth elements (HREE). The chondrite normalized patterns of REEs showed enrichment of LREEs over HREEs with La/Yb of 13.6 while the chondrite normalized value showed low (Gd/Yb)N ratios (2.12) which was illustrated in the flat HREE pattern. The chondrite normalized REE patterns of sediments showed the enrichment of LREE and depletion of HREE. From our findings, REEs concentrations in the study area were found to be of geogenic origins and the distributions were not influenced by anthropogenic sources.

关键词： Rare Earth Elements marine Sediments Redang Island malaysia

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蓝菌Westiellopsis prolifica中藻胆体、藻胆蛋白的共振Raman光谱

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科学通报 1992年第6期37卷 550-553页

作者：夏安东张新夷 m.Sudha P.S.maruthi Sai I.b.Jha 中国科学院长春物理研究所长春130021 School of Life Sciences Jawaharlal Nehru University New Delhi India

在蓝菌和红藻中,藻胆体(phycobilisomes,简称PbS)作为一种超分子聚集体,具有吸收光能且将光能逐步传递到光合反应中心的功能。蓝菌Westiellopsis prolifica的PbS中含有藻红蓝蛋白(phycoerythrocyanin,简称PEC,其吸收峰在570nm附近),C-... 详细信息

在蓝菌和红藻中,藻胆体(phycobilisomes,简称PbS)作为一种超分子聚集体,具有吸收光能且将光能逐步传递到光合反应中心的功能。蓝菌Westiellopsis prolifica的PbS中含有藻红蓝蛋白(phycoerythrocyanin,简称PEC,其吸收峰在570nm附近),C-藻蓝蛋白(C-phycocyanin,简称C-pc,其吸收峰在615nm附近)和变藻蓝蛋白(allophycocyanin。

关键词：藻胆体藻胆蛋白蓝菌

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儿童胸部淋巴瘤的钆增强影像:是否必要静脉注射对比剂?

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国际医学放射学杂志 2019年第4期 496-497页

作者：任彦 C.T.Arendt m.beeres D.Leithner P.Tischendorf m.Langenbach b.Kaltenbach Department of Diagnostic and Interventional Radiology University Hospital Frankfurt

摘要目的随着对钆对比剂潜在副作用关注度提高,非对比剂mR成像日益受到重视。最近的诸多文献评估了潜在的对比剂脑沉积的风险,促使研究焦点向非对比剂增强替代

关键词：对比剂淋巴瘤静脉注射

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bOTANICAL PESTICIDES: A PROmISING ALTERNATIVE APPROACH FOR POST-HARVEST PRESERVATION OF PULSES

BOTANICAL PESTICIDES: A PROMISING ALTERNATIVE APPROACH FOR P...

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The ⅩⅤth International Plant Protection Congress

作者： P.S.mENDKI H.m.KOTKAR b.K.SALUNKE S.m.UPASANI V.L.mAHESHWARI Department of biochemistry School of Life Sciences North Maharashtra University Jalgaon 425 001 （MS） India Department of biochemistry School of Life Sciences North Maharashtra University Jalgaon 425 001 （MS） India Department of biochemistry School of Life Sciences North Maharashtra University Jalgaon 425 001 （MS） India Department of biochemistry School of Life Sciences North Maharashtra University Jalgaon 425 001 （MS） India Department of biochemistry School of Life Sciences North Maharashtra University Jalgaon 425 001 （MS） India

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普通角闪石的成分——花岗岩类和变质岩形成深度的标志

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地球与环境 1979年第2期 57-62页

作者： m·m·马努伊洛娃 ,b·b·扎鲁宾 ,张湖

类质同象范围宽的普通角闪石,对形成的热力学条件反映很灵敏。它们广泛分布在不同成份的岩浆和变质岩之中,在宽广的温度和压力范围内均稳定。因此,用这种矿物来区别岩石形成的热力学条件的企图是很诱人的。

关键词：普通角闪石阳离子单斜闪石正离子花岗岩类变质岩

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Synthesis of Novel Acid Dyes with Coumarin moiety and Their Utilization for Dyeing Wool and Silk Fabrics

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Open Journal of medicinal Chemistry 2016年第1期6卷 18-35页

作者： mahmoud S. bashandy Fatma A. mohamed mohamed m. El-molla mahmoud b. Sheier Ahmed H. bedair Chemistry Department Faculty of Science (Boys) Al-Azhar University Cairo Egypt Chemistry Department University College in Al-Jamoum Umm Al-Qura University Makkah Saudi Arabia Textile Research Division National Research Centre Giza Egypt balguenvzh University College Department of Female Student Umm Al-Qura University Makkah Saudi Arabia Chemistry Department College of Sciences & Art Al Jouf University El-Quraiat Saudi Arabia

This article describes the synthesis of some novel coumarin compounds to use as acid dyes by using compounds 1 - 4 as starting materials, which were prepared by interaction of 2-hydroxybenzaldehyde with ethyl 3-oxobutanoate, diethylmalonate, 4-nitrobenzenediazonium chloride and 4-sulfobenzenediazonium chloride, respectively. Compound 1 reacted with bromine and 2-cyanoacetohydrazide to give phenacyl bromide derivative 5 and 2-cyanoacetohydrazone derivative 6, respectively. Coupling of compound 6 with equimolar amount of 2-sulfo-4-((4-sulfophenyl) diazenyl)benzenediazonium chloride gave coumarin acid dye 8. Phenacyl bromide derivative 5 re-acted with potassium cyanide in refluxing ethanol to produce compound 7, which on coupling with equimolar amount of 8-hydroxy-6-sulfonaphthalene-2-diazonium chloride and 8-hydroxy-3,6-disulfonaphthalene-1-diazonium chloride gave coumarin acid dyes 9 and 10, respectively. Interaction of compound 2 with 2-amino-5-((4-sulfophenyl)diazenyl)benzenesulfonic acid, benzene-1,4-diamine and 3,3’-dimethoxy-[1,1’-biphenyl]-4,4’-diamine in refluxing ethanol afforded compounds 11, 12 and 14, respectively. Diazonium sulphate of compounds 12 and 14 coupling with 4-amino-5-hydroxynaphthalene-2,7-disulfonic acid gave compounds 13 and 15, respectively. Cyclocondensation of compound 3 with ethyl 3-oxobutanoate, diethyl malonate and malononitrile afforded derivatives of 3-acetyl-2H-chromen-2-one 16, ethyl 2-oxo-2H-chromene-3-carboxylate 17 and 2-imino-2H-chromene-3-carbonitrile 18, respectively. Reaction of sodium benzenesulfonate derivative 4 with ethyl 3-oxobutanoate and hydrazine hydrate gave compounds 19 and 20, respectively. The structures of the newly synthesized compounds were confirmed by elemental analysis, UV/ VIS, IR, 1H NmR and ms spectral data. The suitability of the prepared dyestuffs for dyeing of wool and silk fabrics has been investigated. The dyed fabric shows good light fastness, very good rubbing, perspiration, washing and excellent

关键词： Synthesis Coumarin Acid Dye Dyeing Wool Fabric

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Nanoscale resetting of the Th/Pb system in an isotopically-closed monazite grain: A combined atom probe and transmission electron microscopy study

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Geoscience Frontiers 2019年第1期10卷 65-76页

作者： A.-m.Seydoux-Guillaume D.Fougerouse A.T.Laurent E.Gardés S.m.Reddy D.W.Saxey Univ Lyon UJM-Saint-Etienne CNRS IRD CNRS Université Clermont Auvergne School of Earth and Planetary Sciences Curtin University Geoscience Atom Probe Advanced Resource Characterisation Facility John de Laeter Centre Curtin University Centre de recherche sur les Ions les Matériaux et la Photonique (CIMAP) Department of Physics and Astronomy Curtin University

Understanding the mechanisms of parent-daughter isotopic mobility at the nanoscale is key to rigorous interpretation of Ue The Pb data and associated dating. Until now, all nanoscale geochronological studies on geological samples have relied on either Transmission Electron microscope(TEm) or Atom Probe microscopy(APm) characterizations alone, thus suffering from the respective weaknesses of each technique. Here we focus on monazite crystals from a ~1 Ga, ultrahigh temperature granulite from Rogaland(Norway). This sample has recorded concordant UeP b dates(measured by LA-ICP-mS) that range over 100 my, with the three domains yielding distinct isotopic Ue Pb ages of 1034 ± 6 ma(D1; Srich core), 1005 ± 7 ma(D2), and 935 ± 7 ma(D3), respectively. Combined APm and TEm characterization of these monazite crystals reveal phase separation that led to the isolation of two different radiogenic Pb(Pb*) reservoirs at the nanoscale. The S-rich core of these monazite crystals contains Cae Srich clusters, 5 -10 nm in size, homogenously distributed within the monazite matrix with a mean interparticle distance of 40 -60 nm. The clusters acted as a sink for radiogenic Pb(Pb*) produced in the monazite matrix, which was reset at the nanoscale via Pb diffusion while the grain remained closed at the micro-scale. Compared to the concordant ages given by conventional micro-scale dating of the grain,the apparent nano-scale age of the monazite matrix in between clusters is about 100 myr younger, which compares remarkably well to the duration of the metamorphic event. This study highlights the capabilities of combined APm-TEm nano-structural and nano-isotopic characterizations in dating and timing of geological events, allowing the detection of processes untraceable with conventional dating methods.

关键词： monazite Nanoscale resetting Nano-clusters APm TEm UHT metamorphism

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Evaluation of Antioxidants, Total Phenolics and Antimicrobial Activities of Ethyl Acetate Extracts From Fungi Grown on Rice Straw

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Journal of Renewable materials 2019年第7期7卷 667-682页

作者： bahaa T.Shawky mohammed Nagah mosad A.Ghareeb Gamal m.El-Sherbiny Saad A.m.moghannem mohamed S.Abdel-Aziz microbial Chemistry Department National Research CentreDokki-12622CairoEgypt medicinal Chemistry Department Theodor Bilharz Research InstituteKornaish El-NileWarrak El-HadarImbaba(P.O.30)Giza 12411Egypt botany and microbiology Department Faculty of ScienceAzhar UniversityNasr CityCairoEgypt

Rice straw(RS)collected from Egyptian agricultural environment(Al-masied village-Alsharqia Governorate-Egypt)was used as substrate for three fungal isolates namely:4b,1Asp,Pleurotus ostreatus NRRL 3501 and mixed culture of(4b,1Asp).Isolates number 4b and 1Asp were identified using the molecular technique(18S rRNA).Isolate 4b and 1Asp,were identified as Trichoderma saturnisporum mN1-EGY and Aspergillus niger mN2-EGY,*** saturnisporum mN1-EGY extract exhibited the highest antimicrobial activity compared to the other fungal *** phenolic,antimicrobial and antioxidant activities were also determined from the ethyl acetate extract of rice straw inoculated by these *** antioxidant scavenging concentration(SC50)values of the tested samples were 88.84,91.45,94.65 and 100.0μg/ml,respectively for Pleurotus sp.,Aspergiluus niger,Aspergiluus niger+Trichoderma sp.,and Trichoderma sp.,after 15 days incubation,compared to ascorbic acid as positive control with SC50 value equal to 8.0μg/*** phenolic contents(TPCs)were maximum in Pleurotus *** and found to be the most polyphenolic enriched sample(380.64 mg GAE/g dry extract)compared to extracts of Aspergiluusniger,Aspergiluus niger+Trichoderma sp.,and Trichoderma sp.(261.89,198.52,and 119.80 mg GAE/g dry extract),*** GC-mS analysis has been also performed for the promising extracts.

关键词： Rice straw fungi molecular identification antimicrobial antioxidant total phenolics

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Water Use in Sugar and Ethanol Industry in the State of Sao Paulo(Southeast brazil)

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Journal of Sustainable bioenergy Systems 2013年第2期3卷 135-142页

作者： Luiz A.martinelli Solange Filoso Cecilia de barros Aranha Silvio F.b.Ferraz Tatiana m.b.Andrade Elizabethe de C.Ravagnani Luciana Della Coletta Plinio barbosa de Camargo CENA-USP PiracicabaBrazil Chesapeake biological Laboratory University of Maryland Center for Environmental ScienceSolomonsUSA Departamento de Aguas e Energia Eletrica do Estado de Sao Paulo PiracicabaBrazil Departamento de Ciencias Florestais ESALQ-USPPiracicabaBrazil

brazil is the largest producer of ethanol from sugarcane in the world. While the ethanol industry is economically important to brazil for several reasons, it also has a significant impact on the environment. Here we analyze the water consumptive use in the transformation of the feedstock (sugarcane) into ethanol and the impact of industrial byproduct effluents on water resources of the state of Sao Paulo, brazil. Our estimates indicated that in the 2007-2008 harvest, 700 million m3 was withdrawn mainly from rivers and streams by 140 mills, and of this total 440 million m3 was consumed which yielded a water use of approximately 1.53 m3 ·water·tonˉ1 sugarcane or approximately 18 L·water·L-ˉ1 ethanol. At the same time, a total of 120 million m3 of vinasse by-product was produced in the state, equivalent to an organic load of approximately 3 billion kg·bOD during the harvest season or approximately 8 million kg·bOD·dˉ1. Although the water used by sugarcane mills has decreased in recent decades, it is still possible to further decrease the amount of water used by ethanol production. This would decrease the pressure on 1st order streams of the state from which most water is withdrawn. In addition, the enormous volume of vinasse production must be reduced because it exerts constant pressure on aquatic ecosystems, soil and groundwater due to the constant increase in the potassium (K) concentration in areas where it is used as a fertilizer.

关键词： Sugarcane Ethanol Vinasse Water Use Water Resources Rivers brazil

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