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Monoclonal antibody-based ELISA and colloidal gold-based immunochromatographic assay for streptomycin residue detection in milk and swine urine

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Journal of Zhejiang University-Science B(Biomedicine & biotechnology) 2010年第1期11卷 52-60页

作者： Jian-xiang WU Shao-en ZHANG Xue-ping ZHOU institute of biotechnology Zhejiang University Hangzhou 310029 China Nankai biotechnology Limited Company Hangzhou 310051 China

A protein conjugate of streptomycin （streptomycin-bovine serum albumin （BSA） conjugate） was prepared and used as immunogen to produce monoclonal antibodies （MAb）. One hybridoma secreting anti-streptomycin MAb was obtained and then used to produce MAb. The MAb named 13H5 showed the 50% maximal inhibitory concentra- tion （IC50） value of 4.65 ng/ml and the IC20value of 0.21 ng/ml in phosphate buffered saline （PBS）. At optimum con- ditions, an indirect competitive enzyme-linked immunosorbent assay （ELISA） and a colloidal gold-based immuno- chromatographic assay （CGIA） were developed and applied to detect streptomycin residues in milk and swine urine samples. The developed ELISA showed that the minimum detection limit was 2.0 and 1.9 ng/ml for milk and swine urine samples, respectively, without obvious cross-reactivity to other tested antibiotics except dihydrostreptomycin which gave a 118.32% cross reaction value. Milk and swine urine samples spiked with streptomycin at 10, 50, 100 and 200 ng/rnl were analyzed by the established ELISA. The mean recovery of streptomycin was from 81.9% to 105.5% and from 84.3% to 92.2% for milk and swine urine, respectively. The optimized CGIA showed that the minimum de- tection limit was 20.0 ng/ml for milk and swine urine samples. The results of spiked analysis and specific analysis demonstrate that the CGIA could be applicable for screening milk and swine urine samples for the presence of streptomycin residues on-site. The established ELISA and CGIA allow the rapid, low-cost, and sensitive determination of streptomycin residues in food samples.

关键词： Streptomycin Monoclonal antibody Antibiotic residue Enzyme-linked immunosorbent assay (ELISA) Colloidal gold-based immunochromatographic assay (CGIA)

Evaluation of Bacillus sp. MZS10 for decolorizing Azure B dye and its decolorization mechanism

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Journal of Environmental Sciences 2014年第5期26卷 1125-1134页

作者： Huixing Li Ruijing Zhang Lei Tang Jianhua Zhang Zhonggui Mao The Key Laboratory of Industrial biotechnology Ministry of Education School of Biotechnology Jiangnan University School of Biological and Chemical Engineering Nanyang Institute of Technology

To evaluate decolorization and detoxification of Azure B dye by a newly isolated Bacillus sp. MZS 10 strain, the cultivation medium and decolorization mechanism of the isolate were investigated. The decolorization was discovered to be dependent on cell density of the isolate and reached 93.55% （0.04 g/L） after 14 hr of cultivation in a 5 L stirred-tank fermenter at 2.0 g/L yeast extract and 6.0 g/L soluble starch and a small amount of mineral salts. The decolorization metabolites were identified with ultra performance liquid chromatography-tandem mass spectroscopy （UPLC-MS）. A mechanism for decolorization of Azure B was proposed as follows： the C=N in Azure B was initially reduced to -NH by nicotinamide adenine dinucleotide phosphate （NADPH）-dependent quinone dehydrogenase, and then the -NH further combined with -OH derived from glucose to form a stable and colorless compound through a dehydration reaction. The phytotoxicity was evaluated for both Azure B and its related derivatives produced by Bacillus sp. MZS 10 decolorization, indicating that the decolorization metabolites were less toxic than original dye. The decolorization efficiency and mechanism shown by Bacillus sp. MZS10 provided insight on its potential application for the bioremediation of the dye Azure B.

关键词： Azure B Bacillus sp. decolorization ultra performance liquid chromato graphy-tandem mass spectroscopy phytotoxicity

Preparation of LDPE-Acetylated/Butyrylated Starch Blend Blow Films and Characterization

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Chinese Journal of Polymer Science 2014年第3期32卷 268-279页

作者： Sangeeta Garg Asim Kumar Jana Department of Chemical Engineering National Institute of TechnologyJalandhar Department of biotechnology National Institute of TechnologyJalandhar

Development of modified plastics has been studied through the LDPE-acylated starch blend films to examine the effect of different acyl groups and degrees of substitution （DS） on properties of films. Corn starch was modified with acetyl and hutyryl groups and films were prepared by blending acylated starch with low density polyethylene （LDPE）. Systematic studies were done to observe the effect of acyl groups, DS and starch concentration on the properties and biodegradability of the blend films. It was observed that blend films containing 5% acetylated and butyrylated starches of high DS （2.5, 1.7） maintained 75% and 83% of tensile strength of LDPE films. Thermal analysis results indicated that acetylated and butyrylated starch blend films decomposed at 370℃ and 389℃ which were higher than the decomposition temperature of native starch film （349℃）. Scanning electron micrographs of blend films containing high DS acylated starch showed well dispersed starch particles due to improvement in dispersion between starch and LDPE. Water absorption capacity of high DS acetylated and butyrylated starch blend films （4.18% and 3.76%, respectively） was lower than that of native starch films （5%）. This study has an advantage because of blown films prepared can be integrated with the present manufacturing systems without any other requirement.

关键词： Acylated starch LDPE-starch blend films Mechanical properties Water absorption capacity Biodegradability.

Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第01期 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

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Molecular characterization of Tomato yellow leaf curl China virus and its satellite DNA isolated from tobacco

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Science Bulletin 2003年第8期48卷 766-770页

作者： XIE Yan, ZHOU Xueping & LI Guixin institute of biotechnology, Zhejiang University, Hangzhou 310029, China Correspondence should be addressed to Zhou Xueping (e-mail: zzhou@***) institute of biotechnology Zhejiang University China

Virus isolates, Y8, Y36 and Y38, were obtained from tobacco plants showing leaf curl symptoms in Honghe, Yunnan Province. In reactions with 14 monoclonal antibod-ies raised against Begomovirus particles, Y8, Y36 and Y38had similar antigenic reaction in TAS-ELISA as Tomato yel-low leaf curl China virus (TYLCCNV). The complete DNA-A nucleotide sequences of Y8, Y36 and Y38 were determinedand they contain 2727, 2730 and 2730 nucleotides, respec-tively. Each of the DNA-A sequences has a typical Bego-movirus genome organization encoding 6 ORFs with 2 ORFs [AV1(CP) and AV2] in virion-sense DNA and 4 ORFs (AC1to AC4) in complementary-sense DNA. Comparisons withtotal DNA-A, intergenic region and deduced amino acid se-quences of individual ORFs show that Y8, Y36 and Y38 are isolates of TYLCCNV. Satellite DNA molecules (DNAb) were found to be associated with Y8, Y36 and Y38, which consist of 1338, 1339 and 1338 nucleotides, respectively. Compari-sons show that these DNAb molecules share 98%—99% se-quence identities on nucleotide level and have a commonORF (designated C1) encoding 126 amino acids on the com-plementary strand.

关键词： Tomato yellow leaf curl China virus DNAb sequence Begomovirus.

Molecular characterization and expression patterns of Nanog gene validating its involvement in the embryonic development and maintenance of spermatogonial stem cells of farmed carp,Labeo rohita

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Journal of Animal Science and biotechnology 2018年第4期9卷 824-840页

作者： Swagat K.Patra Chakrpani Vemulawada Meenati M.Soren Jitendra K.Sundaray Manoj K.PANDa Hirak K.Barman Fish Genetics and biotechnology Division ICAR-Central Institute of Freshwater Aquaculture Center of biotechnology Siksha 'O' Anusandhan University

Background: The homeobox containing transcription factor Nanog plays crucial roles in embryonic development/proliferation and/or maintenance of spermatogonial stem cells(SSCs) via interacting with transcription factors such as Oct4 and Sox2 in mammals. However, knowledge of its exact mechanistic pathways remains unexploited. Very little is known about teleost Nanog. Information on the Nanog gene of farmed rohu carp(Labeo rohita) is lacking. We cloned and characterized the Nanog gene of rohu carp to understand the expression pattern in early developmental stages and also deduced the genomic organization including promoter ***: Rohu Nanog(LrNanog) cDNA comprised an open reading frame of 1,161 nucleotides bearing a structural homeodomain; whereas, the genomic structure contained four exons and three introns suggesting that it is homologous to mammalian counterparts. Phylogenetical y, it was closely related to freshwater counterparts. Protein sequence(386 AA of42.65 kDa) comparison revealed its low similarity with other vertebrate counterparts except that of the conserved homeodomain. Tissue distribution analysis revealed the existence of LrNanog transcripts only in adult gonads. The heightened abundances in the ovary and proliferating spermatogonia suggested its participations in maternal inheritance and male germ cell development. The potentiating abundances from fertilized egg onwards peaking at blastula stage vis-à-vis decreasing levels from gastrula stage onwards demonstrated its role in embryonic stem cell development. We also provided evidence of its presence in SSCs by western blotting analysis. Further, the promoter region was characterized, predicting a basal core promoter and other consensus ***: The molecular characterization of LrNanog and its documented expression profiling at transcript and protein levels are indicative of its functional linkage with embryonic/spermatogonial stem cell maintenance. This is the first report of L

关键词： Embryonic stages Gene expression Nanog Promoter analysis Rohu(Labeo rohita) Spermatogonial cell

Sequence analysis and expression pattern of MGTA1 gene in rice blast pathogen Magnaporthe grisea

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Journal of Zhejiang University-Science B(Biomedicine & biotechnology) 2005年第8期6卷 817-824页

作者：王教瑜刘小红卢建平林福呈 biotechnology institute School of Agriculture and Biotechnology Zhejiang UniversityHangzhou 310029 China Microbiology institute School of Life Sciences Zhejiang UniversityHangzhou 310029 China

MGTA1, a putative fungal Zn（Ⅱ）2Cys6 transcriptional activator-encoding gene, was isolated from rice blast pathogen Magnaporthe grisea, which is homologous to CLTA1 from Colletotrichum lindemuthianum with 51% identity at protein level. MGTA1 cassette contains a 2370 bp open reading frame, consisting of 6 exons, coding a 790 amino acid peptide. MGTA1 gene exists as a single copy in genomes of 7 strains of M. grisea, and is expressed in tip hyphae, conidia, and mature appressoria of strain Guy 11.

关键词： Magnaporthe grisea MGTA1 gene Zn(Ⅱ)2Cys6

The kinesin-like proteins, KAC1/2, regulate actin dynamics underlying chloroplast light-avoidance in Physcomitrella patens

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Journal of Integrative Plant Biology 2015年第1期57卷 106-119页

作者： Zhiyuan Shen Yen-Chen Liu Jeffrey P.Bibeau Kyle P.Lemoi Erkan Tüzel Luis Vidali Department of Biology and biotechnology Worcester Polytechnic Institute Department of Physics Worcester Polytechnic Institute

In plants, light determines chloroplast position; these organelles show avoidance and accumulation re- sponses in high and low fluence-rate light, respectively. Chloroplast motility in response to light is driven by cytoskeletal elements. The actin cytoskeleton mediates chloroplast photorelocation responses in Arabidopsis thali- ana. In contrast, in the moss Physcomitrella patens, both, actin filaments and microtubules can transport chloroplasts. Because of the surprising evidence that two kinesin-like proteins （called KACs） are important for actin-dependent chloroplast photorelocation in vascular plants, we wanted to determine the cytoskeletal system responsible for the function of these proteins in moss. We performed gene- specific silencing using RNA interference in P. patens. We confirmed existing reports using gene knockouts, that PpKAC1 and PpKAC2 are required for chloroplast dispersion under uniform white light conditions, and that the two proteins are functionally equivalent. To address the specificcytoskeletal elements responsible for motility, this loss-of- function approach was combined with cytoskeleton-targeted drug studies. We found that, in P. patens, these KACs mediate the chloroplast light-avoidance response in an actin filament- dependent, rather than a microtubule-dependent manner. Using correlation-decay analysis of cytoskeletal dynamics, we found that PpKAC stabilizes cortical actin filaments, but has no effect on microtubule dynamics.

关键词： Actin filaments cytoskeleton intracellular transport kinesin-14 light-avoidance response microtubule moss RNAi

CRISPR-based genetic control strategies for insect pests

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Journal of Integrative Agriculture 2023年第3期22卷 651-668页

作者： Ying YAN Roswitha A.AUMANN Irina HÄCKER Marc F.SCHETELIG Department of Insect biotechnology in Plant Protection Institute for Insect BiotechnologyJustus-Liebig-University GiessenGiessen 35394Germany

Genetic control strategies such as the sterile insect technique have successfully fought insect pests worldwide. The CRISPR(clustered regularly interspaced short palindromic repeats) technology, together with high-quality genomic resources obtained in more and more species, greatly facilitates the development of novel genetic control insect strains that can be used in area-wide and species-specific pest control programs. Here, we review the research progress towards state-of-art CRISPR-based genetic control strategies, including gene drive, sex ratio distortion, CRISPRengineered genetic sexing strains, and precision-guided sterile insect technique. These strategies’ working mechanisms,potential resistance development mechanisms, and regulations are illustrated and discussed. In addition, recent developments such as stacked and conditional systems are introduced. We envision that the advances in genetic technology will continue to be one of the driving forces for developing the next generation of pest control strategies.

关键词： insect pest genetic control sterile insect technique gene drive genetic sexing strains CRISPR-Cas9