Please use this identifier to cite or link to this item:
標題: 弧菌分子分型與其攝鐵系統對生長及致病性之探討
Molecular identification and the influence of iron uptake system on the growth and virulence of Vibrio spp.
作者: 瑋, 鄭倉
Cheng, Tsang-Wei
關鍵字: Vibrio spp.
iron uptake system

出版社: 獸醫學系
摘要: 弧菌感染不僅為水生動物常見的疾病之一,亦是食品公共衛生上重要 病原菌。因此,弧菌的分離與快速鑑定就顯得格外重要。以11組隨機引子 進行隨機增幅多型性聚合酵素連鎖反應 ( random amplified polymorphic DNA PCR;RAPD PCR )所建立之細菌 DNA 多型性片段,可作 為各種菌株的鑑定與分型,這些菌株包括 V. anguillarum、V. parahaemolyticus、V. vulnificus、V. cholerae 與 V. damsela 等幾 種常見弧菌,此方法可作為日後應用於弧菌快速診斷之參考。另一方面, 鐵元素為細菌生長所需之必要元素之一,細菌為了競爭取得鐵元素,最常 利用的方式為分泌 siderophore 來獲取環境中之鐵,以供其生長所需。 由實驗得知各受測弧菌對環境中限鐵的耐受能力有所差異,其中以 V. tubiashii (VT-1) 之耐受限鐵能力最高,於1200 uM 限鐵物質 (2,2*-dipyridyl ) 下,其細菌數可達107 CFU/ml,V. parahaemolyticus 耐受限鐵能力次之,V. anguillarum 與 V. vulnificus 最低。又VT-1之細胞外產物可影響其他弧菌的生長;限鐵環 境下,VT-1萃出物可抑制 V. anguillarum、 V. parahaemolyticus 與 V. vulnificus 的生長。此外,環境中之鐵元素亦會影響弧菌 siderophore 的分泌,當環境中鐵元素少時,會誘使弧菌產生較多量 siderophore。不僅如此,弧菌外產物毒性會受限鐵程度的不同而有所改 變;利用吳郭魚之紅血球與 CHSE-214 cell line ( Chinook salmon embryo-214 cell line ) 進行毒力試驗,皆顯示於限鐵環境下,弧菌毒 力有明顯增加之趨勢。另一方面,針對V. anguillarum 設計一組 fur ( ferric uptake regular )基因引子,分別對 V. anguillarum、V. parahaemolyticus、V. harveyi 與 V. tubiashii 進行偵測,將所得之 V. tubiashii 預期產物進行定序與比對,其結果顯示與其他弧菌之同源 性為69~99%。
Vibrio spp. are important pathogenic bacteria of aquatic animals and also caused massive disease including diarrhea, enteritis and toxiemia in human. In this study, random amplified polymorphic DNA polymerase chain reaction (RAPD PCR) method was applied and successfully established the DNA fingerprinting of important Vibrio spp. such as V. anguillarum, V. parahaemolyticus, V. vulnificus, V. cholerae and V. damsela. This result suggested RAPD PCR provide another rapid identification method if in comparison with the traditional biochemical tests of Vibrio spp.. Most Vibrio spp. can only survive under moderate iron limiting condition (250~400 uM 2,2*-dipyridyl), but V. tubiashii ( VT-1 ) showed more resistant to extremely highly iron limiting condition ( >1200 uM 2,2*-dipyridyl). When V. tubiashii ( VT-1 ) extrate was added along with V. parahaemolyticus, V. anguillarum and V. vulnificus culture, all tested Vibrio strains showed consequential influence of growth rate in each group. In addition, Vibrio spp. had various activity for secreting siderophore in different concentrations of 2,2*-didyridyl. Also, their extracellular products can increase the hemolytic activity and cellular toxicity by detecting with erythrocyte of Tilapia mossambica and CHSE-214 cell line. Furthermore, the sequence analysis using automatic fluorescent DNA sequencing indicated that the homogeneity of the partial fur genes among those Vibrio spp. were among 69 to 99%.
Appears in Collections:獸醫學系所



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.