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1.
Antimicrobial peptides are a class of proteins with antibacterial functions. In this study, the anti-lipopolysaccharide factor isoform 3 gene (ALFPm3), encoding an antimicrobial peptide from Penaeus monodon with a super activity was expressed in Chlamydomonas reinhardtii, which would develop a microalga strain that can be used for the antimicrobial peptide production. To construct the expression cluster, namely pH2A-Pm3, the codon optimized ALFPm3 gene was fused with the ble reporter by 2A peptide and inserted into pH124 vector. The glass-bead method was performed to transform pH2A-Pm3 into C. reinhardtii CC-849. In addition to 8 μg/mL zeocin resistance selection, the C. reinhardtii transformants were further confirmed by genomic PCR and RT-PCR. Western blot analysis showed that the C. reinhardtii-derived ALFPm3 (cALFPm3) was successfully expressed in C. reinhardtii transformants and accounted for 0.35% of the total soluble protein (TSP). Furthermore, the results of antibacterial assay revealed that the cALFPm3 could significantly inhibit the growth of a variety of bacteria, including both Gram-negative bacteria and Gram-positive bacteria at a concentration of 0.77 μM. Especially, the inhibition could last longer than 24 h, which performed better than ampicillin. Hence, this study successfully developed a transgenic C. reinhardtii strain, which can produce the active ALFPm3 driven from P. monodon, providing a potential strategy to use C. reinhardtii as the cell factory to produce antimicrobial peptides. 相似文献
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抗菌肽与抗生素的体外抗菌效果比较 总被引:17,自引:0,他引:17
应用由 Hancock实验室改进的微量肉汤稀释法测定了 cecropin P1、cecropin A、magainin 2、defensin 1、bactenecin、lactoferricin和 indolicidin等 7种抗菌肽和盐酸金霉素、去甲万古霉素、土霉素、强力霉素等 4种抗生素的体外抗菌活性 ,并且使用薄层琼脂糖孔穴扩散法比较了抗菌肽中 cecropin P1和 cecropin A与土霉素和呋喃唑酮对大肠杆菌 K88的抑菌效果。结果发现 ,抗菌肽与抗生素一样对几种革兰氏阳性菌和阴性菌都有不同程度的抗菌效果。其中 cecropin A、cecropin P1和 defensin1对大肠杆菌的 2个菌株 ATCC2 5 92 2和 K88的抗菌活性高于抗生素 ,defensin1是各种抗菌肽中对金黄色葡萄球菌抗菌效果最好的。抗生素对试验用金黄色葡萄球菌的抑制活性总体上要好于抗菌肽。与抗生素相比 ,cecropin A、cecropin P1和 indolicidin对猪霍乱沙门氏菌和鼠伤寒沙门氏菌具有更好的抗菌效果。另外 ,抗菌肽的抑菌圈边缘十分清晰 ,而抗生素的整个抑菌圈都比较模糊且界线不明。因此 ,从抗菌效果方面考虑 ,抗菌肽可以代替抗生素用于疾病的预防和治疗 相似文献
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Landscape-ecological mapping of the Netherlands 总被引:1,自引:0,他引:1
Kees J. Canters Cees P. den Herder Aart A. de Veer Paul W. M. Veelenturf Rein W. de Waal 《Landscape Ecology》1991,5(3):145-162
The Landscape-ecological Mapping of the Netherlands project (LMN project) started in 1983 with the aim of establishing a landscape-ecological database for use in developing and evaluating national land-use plans. The project, working with grid cells of 1 km2, has four working objectives: a) development of mapping potential for basic landscape-ecological data, b) assessment of susceptibility to interventions, c) evaluation of significance for nature conservation and d) production of vulnerability maps, as a combination of susceptibility and significance. In addition to information on soil, groundwater, ecotopes, flora and fauna, the database also incorporates information on physiographical features and entire landscapes. The resulting database is a geographic information system (GIS). This article describes the second phase of the project (1985–1989), covering the Randstad area, and focusses on the methods and the applications potential of the database. 相似文献
5.
Evans EW Harmon BG 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1995,24(4):109-116
Cationic antimicrobial peptides are present throughout the plant and animal kingdoms and bear striking structural and functional similarities across species lines. They provide primitive, nonspecific means of combating a variety of bacteria, fungi, enveloped viruses, and protozoa. Some are also cytotoxic against host cells, including neoplastic cells. Cationic antimicrobial peptides may play various roles in inflammation and tissue repair. Antimicrobial peptides are found in epithelial tissues regularly exposed to microbial attack as well as in cells whose primary function is defense against potential pathogens. They constitute an important part of the nonoxidative antimicrobial arsenal of leukocytes. They are preformed and/or readily synthesized when the cells are stimulated by exposure to pathogens. They exert their effects directly by inserting into membranes of target cells and forming ion channels which increase membrane permeability; however, antimicrobial peptides can also act as opsonins to facilitate phagocytosis. Resistance to defensins is a virulence factor for organisms such as Salmonella sp. The study of cationic antimicrobial peptides is increasing our understanding of innate immunity, inflammation, and the pathogenesis of genetic diseases such as specific granule disease in humans. Therapeutic applications of antimicrobial peptides are currently under investigation. 相似文献
6.
Pot experiments were conducted to evaluate the level of imazamox tolerance in five red rice ( Oryza sativa L.) and four barnyardgrass (three Echinochloa crus-galli (L.) Beauv. and one Echinochloa oryzoides (Ard.) Fritch) morphologically distinct biotypes collected from rice fields in northern Greece. The susceptibility of barnyardgrass biotypes to propanil was also studied. Red rice biotypes were not controlled by imazamox applied at 40 g ha−1 . In contrast, 80 g imazamox ha−1 provided 56–84% red rice control (averaged across shoot number and fresh weight reduction). Not all barnyardgrass biotypes were susceptible to imazamox applied postemergence. However, propanil applied at 2.6 kg ha −1 controlled the E. crus-galli biotypes well, but propanil applied at rates of 2.6 and 5.2 kg ha −1 was not effective in reducing the shoot number and fresh weight of the E. oryzoides biotype. Propanil applied at 10.4 kg ha −1 reduced the shoot number and fresh weight of this biotype by 78 and 85%, respectively. In most cases, a linear equation ( y = % of control, x = g ha−1 ) provided the best fit for regressions between red rice or barnyardgrass shoot number or fresh weight and imazamox rates. The results of this study suggest that postemergence application of imazamox is not effective against all red rice and barnyardgrass biotypes found in the rice fields of Greece and that significant variability regarding herbicide efficacy among biotypes might exist. 相似文献
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Barriers to and enablers of implementing antimicrobial stewardship programs in veterinary practices 下载免费PDF全文
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2016年5月河北省秦皇岛市昌黎县某海水养殖基地半滑舌鳎突发大批死亡,为了确定引起死亡的病原菌,无菌采集心血进行病原菌分离鉴定,16S rDNA基因序列分析与GenBank中公布的美人鱼发光杆菌参考株序列同源性为99.6%,被鉴定为美人鱼发光杆菌;进一步通过生化特性分析,被确认为美人鱼发光杆菌美人鱼亚种。动物回归试验结果表明,其对舌鳎鱼具有很强的致病性,其LD_(50)为3.1×10~4CFU/mL,且对哺乳动物具有致病性。药敏试验结果显示,分离菌对诺氟沙星、恩诺沙星、环丙沙星,乙酰甲喹高度敏感;对多西环素、阿米卡星中敏感;对庆大霉素、头孢曲松、替米考星等不敏感。 相似文献
10.
世界动物卫生组织(OIE)是动物卫生领域的权威国际组织。通过研究OIE相关标准和策略,为我国进一步加强兽用抗生素管理,更好地防治抗生素耐药性风险提供参考意见。 相似文献