碩士 / 國立臺灣大學 / 海洋研究所 / 91 / Vibrio vulnificus is a facultatively anaerobic, halophilic, Gram-negative bacterium which is widely distributed in estuarine and coastal ecosystems; seafood and water can be vectors for transmission of this pathogenic species to humans. Its infection might result in a variety of clinical syndromes, including gastroenteritis, cellulitis, and septicemia. Enumeration and isolation of V. vulnificus-like bacteria and heterotrophic bacteria in coastal seawater samples were performed. The seawater samples were collected from Badǒuzǐh and Shenào of Keelung, Taiwan during period of March 2001 to January 2002. The study attempted to develop a specific and sensitive method rapid for detection and identification of V. vulnificus distributed in water, fish and shellfish.
Plate counting values of the V. vulnificus-like bacteria in seawater samples were mostly in the range of 0 to 670 CFU/ml. The values accounted for 0-2.25% of the heterotrophic bacteria in these seawater samples. A total of 81 bacterial strains were isolated from the counting plates. They could be divided into eight groups according to the results of the following tests: Gram reaction, requirement of Na+ for growth, glucose fermentation, sensitivity to colistin, growth at 5℃ and 40℃. Group Ⅰ contained 28 Gram-positive, non-fermentative strains. Both halophilic and non-halophilic bacteria were included in this group. All the other groups contained only Gram-negative bacteria. Group Ⅱ contained 13 strains which did not require Na+ for growth. Group Ⅲ contained 10 strains which did not ferment glucose. The strains included in were not group Ⅳ did not sensitive to colistin. Not any of the groups Ⅰ, Ⅱ, Ⅲ and Ⅳ included V. vulnificus. Groups Ⅴ, Ⅵ, Ⅶ and Ⅷ contained strains that were glucose-fermentative, colistin-resistant, and Gram-negative strains. Thus all the four groups might include Vibrio vulnificus. Both group Ⅴ and group Ⅵ grew at 40℃, while only the former group grew at 5℃. Both group Ⅶ and group Ⅷ did not grow at 40℃, while only group Ⅶ grew at 5℃.
Six pairs of specific primers directed against the 23S rRNA gene (rDNA) of V. vulnificus were designed. Among them a pair of specific primers, designated Vv23SF3 / Vv23SR3 proved to be more feasible for identification of V. vulnificus than the other five pairs of primers. Use of Vv23SF3 / Vv23SR3 in colony PCR had a detection limit of 11 cells for V. vulnificus. Use of a suitable selective medium and the primer pair Vv23SF3 / Vv23SR3 in colony PCR would be effective in detection and enumeration of V. vulnificus in estuarine and coastal environment.
Identifer | oai:union.ndltd.org:TW/091NTU00279023 |
Date | January 2003 |
Creators | Chin-Ying Lin, 林金盈 |
Contributors | Wung Yang Shieh, 謝文陽 |
Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
Language | zh-TW |
Detected Language | English |
Type | 學位論文 ; thesis |
Format | 97 |
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