碩士 / 國立臺灣大學 / 海洋研究所 / 91 / Enumeration and isolation of luminous bacteria from seawater and various marine organisms collected from the coastal regions of northern Taiwan were performed in the present study. Plate counts indicated that luminous bacteria in mostly sponge samples (8 out of 13) were in the range between 104 and 105 CFU/g wet wt, while those in the other samples rarely reached 102 CFU/ml or g wet wt. Luminous bacteria accounted for 4.3 to 18.2% of heterotrophic bacteria in some sponge samples (5 out of 13), while only 0 to 3.3% of heterotrophic bacteria in the other samples were found to be luminous.
Forty-five strains of luminous bacteria were isolated from seawater, sponge and marine organisms. All of them were halophilic, facultatively anaerobic, Gram-negative rods, and could be identified as the family of Vibrionaceae. According to morphological and physiological characteristics, these isolates were divided into six groups. The six strains included in groupⅠ could utilize D-mannitol as a sole carbon source for growth. Growth was observed at 40℃, but neither at 4℃ nor 8% NaCl. These strains did not ferment sucrose. GroupⅡ contained one strain and was the only strain could grow at 4℃. The strain fermented sucrose with acid production. GroupⅢsimilar to groupⅠ, consisted of strains that grew at 40℃ and 8% NaCl, but were unable to utilize D-mannitol as a sole carbon source for growth. GroupsⅣ to Ⅵ were distinguished from groupsⅠ to Ⅲ by their ability to grow at 8% NaCl. GroupⅣ contained fourteen strains which could not grow at 4℃ and 40℃. GroupⅤ contained six strains which could ferment sucrose. They were different from groupⅣ in growing at 40℃. GroupⅥ contained seventeen strains. They were similar to groupⅤ that could grow at 40℃and not at 4℃, but the difference between them was the ability of fermenting sucrose.
Compare the 16S rDNA sequences of isolates in the GeneBank database revealed that the representative strains SA2-2, SPN-1, SB1-1, H-4, SB2-3, SA1-1 , SPH1-1 and SPH2-1 of groupⅠ to Ⅵ belonged to either genus Vibrio or genus Photobacterium, respectively. Based on its 16S rDNA sequence and phenotypic characteristics, strain SA2-2 of groupⅠ apparently belonged to P. leiognathi ATCC 25521T (similarity 99.4%). Strain SPN-1 of groupⅡ was most similar to non-luminous bacteria Vibrio campbelli ATCC 25920T(similarity 99.9%), and luminous bacteria V. harveyi ATCC 14126T(similarity 99.2%). Strain SB1-1 of groupⅢ was most similar to non-luminous bacteria Vibrio alginolyticus ATCC 17749T (similarity 99.2%), and luminous bacteria V. harveyi ATCC 14126T(similarity 98.5%). Strain H-4 of groupⅣ was most related with non-luminous bacteria Vibrio natriegens ATCC 14048T(similarity 98.9%), and luminous bacteria V. harveyi ATCC 14126T(similarity 98.2%). Strain SB2-3 of groupⅤ had high similarity with non-luminous bacteria V. campbelli ATCC 25920T(similarity 99.9%), and luminous bacteria V. harveyi ATCC 14126T(similarity 99.1%). Strain SA1-1, SPH1-1 and SPH2-1 of groupⅥ were closely related to non-luminous bacteria V. campbelli ATCC 25920T(99.1% to 99.4%), and luminous bacteria V. harveyi ATCC 14126T(98.6% to 98.9%).
Ten strains to forty-five luminous isolates lost their luminous activity under subculture. However, It was proven that five of these 10 strains could reappear luminous ability in altered culture condition, and one of the others still retain luxA. It showed that the luminous isolates could not maintain their ability of luminance in subculture was not necessarily relative to losing luxA.
| Identifer | oai:union.ndltd.org:TW/091NTU00279028 |
| Date | January 2003 |
| Creators | Hsiao Hui Chou, 周曉慧 |
| Contributors | Wung Yang Shieh, Wen Dar Jean, 謝文陽, 簡文達 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 79 |
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