This experiment was conducted to clarify species and drug resistance of pathogen from the diseased Procambarus clarkia. Pathogenic bacteria from hepatopancreas of the diseased P. clarkia were examined using convention...This experiment was conducted to clarify species and drug resistance of pathogen from the diseased Procambarus clarkia. Pathogenic bacteria from hepatopancreas of the diseased P. clarkia were examined using conventional methods,and then were isolated. The further tests and analysis of the isolated strain were developed,including the regression experiment to P. clarkia,the morphology,physiological and biochemical characteristics,sequence analysis of their 16 S rRNA and gyr B genes,and the susceptibility test to antibiotics. Large colonies with similar morphology and color were obtained. Strain X120523 was identified as Citrobacter freundii,proved to have strong pathogenicity,and was susceptible to quinolones and aminoglycosides.展开更多
Medicinal plants have been presented as a valuable source of preservation of human health. In special, Stryphnodendron barbatiman has been employed due to its antimicrobial activity. This plant is rich in tannins and ...Medicinal plants have been presented as a valuable source of preservation of human health. In special, Stryphnodendron barbatiman has been employed due to its antimicrobial activity. This plant is rich in tannins and has been used in popular medicine for the treatment of gastrointestinal disorder, treatment of lesions, and also as anti-inflammatory microbicide. Citrobacter freundii is a member of the family Enterobacteriaceae and is one of the major causes of opportunistic infections. This microorganism is a bacterium (bacillus) aerobic gram-negative with a length in the range of 1 to 5 mm. C. freundii is commonly found in water, soil, food and occasionally in the gastrointestinal tract of animals and humans. In this paper, we have demonstrated the antibacterial activity of S. barbatiman by observing cellular death by using inhibition halo approach. Atomic force microscopy and FT-IR spectroscopy results suggested that interaction between the main active components of S. barbatiman with cellular wall of C. freundii gives rise to cellular wall damage, and then leads this microorganism to death.展开更多
基金Supported by the Science and Technology Innovative Research Team of Anhui Academy of Agricultural Sciences(14C0504)the Youth Innovation Foundation of President of Anhui Academy of Agricultural Sciences(14B0529)Anhui Aquaculture Industry Technology System for Shrimp and Crab
文摘This experiment was conducted to clarify species and drug resistance of pathogen from the diseased Procambarus clarkia. Pathogenic bacteria from hepatopancreas of the diseased P. clarkia were examined using conventional methods,and then were isolated. The further tests and analysis of the isolated strain were developed,including the regression experiment to P. clarkia,the morphology,physiological and biochemical characteristics,sequence analysis of their 16 S rRNA and gyr B genes,and the susceptibility test to antibiotics. Large colonies with similar morphology and color were obtained. Strain X120523 was identified as Citrobacter freundii,proved to have strong pathogenicity,and was susceptible to quinolones and aminoglycosides.
基金This work was supported by CNPq and Capes (Brazil).
文摘Medicinal plants have been presented as a valuable source of preservation of human health. In special, Stryphnodendron barbatiman has been employed due to its antimicrobial activity. This plant is rich in tannins and has been used in popular medicine for the treatment of gastrointestinal disorder, treatment of lesions, and also as anti-inflammatory microbicide. Citrobacter freundii is a member of the family Enterobacteriaceae and is one of the major causes of opportunistic infections. This microorganism is a bacterium (bacillus) aerobic gram-negative with a length in the range of 1 to 5 mm. C. freundii is commonly found in water, soil, food and occasionally in the gastrointestinal tract of animals and humans. In this paper, we have demonstrated the antibacterial activity of S. barbatiman by observing cellular death by using inhibition halo approach. Atomic force microscopy and FT-IR spectroscopy results suggested that interaction between the main active components of S. barbatiman with cellular wall of C. freundii gives rise to cellular wall damage, and then leads this microorganism to death.
文摘本研究旨在对虹鳟体内分离菌进行分子鉴定分型及耐药性分析。通过形态学观察、生理生化反应、16S rRNA基因比对进化分析及管家基因多位点序列分型等方法,确定分离菌的种属地位、分析种内分子变异特征;利用纸片扩散法与PCR方法,分析分离菌耐药表型与基因型之间关系;进行人工感染小鼠试验,评估分离菌致病力强弱。结果显示,分离菌(GZBJ2017)为革兰氏阴性杆菌;16S rRNA基因与弗氏柠檬酸杆菌16S r RNA基因同源性达95.4%,结合生理生化反应结果,确定分离菌为弗氏柠檬酸杆菌;分离菌7个管家基因均发生变异,多位点序列分型鉴定为新序列型,与标准菌株ST-132亲缘关系最近;分离菌对头孢曲松、多粘菌素B、环丙沙星、氧氟沙星4种药物敏感,对四环素、庆大霉素、泰乐菌素、复方新诺明、青霉素、卡那霉素6种药物耐药;分离菌携带Sul1、Sul2、Intl1等3种耐药基因,与耐药表型相符;人工感染试验结果显示,该菌对小鼠具有一定的致病力。本研究对本次虹鳟发病的病因作出了准确诊断,为虹鳟弗氏柠檬酸杆菌感染的防治与分子流行病学研究提供依据。