Plant terpenoids engance the survivability of PCB(Polychlorinated Biphenyl) degrading pseudomonas pseudoalcaligences KF707 labeled with gfp in microcosms contaminated with PCB : PCB에 오염된 microcosm에서 PCB분해균주인 Pseudomonas pseudoalcaligenes KF707이 plant terpenoid에 의해 survivability의 증가에 관한 연구

다국어 초록 (Multilingual Abstract)

Polychlorinated biphenyls (PCBs) are toxic pollutants and their degradation is quite slow in the environment. Recently, interests in bioremediation using PCB-degrading bacteria have increased. Terpenes are natural substrates with structural similarities to PCB.
They also have been known to be widely present in the environment and relatively non-toxic to human. In a previous report, plant terpenes (p-cymene, (S)-(-)-limonene, a-pynene, and a-terpinene) have been found to be utilized by a PCB degrader and to induce bph (biphenyl dioxygenase) gene in pure culture. Therefore it has been proposed that using terpenes rather than PUB congeners is very useful to stimulate PCB degradation. In this study, Pseudomonas pseudoalcaligenes KF707, a PCB-degrading Gram-negative soil bacterium was used to determine whether the terpenoid stimulation of PCB degrader occurs in natural environment. First, P. pseudoalcaligenes KF707 was genetically tagged using transposon with gfp (green fluorescent protein) as a reporter gene. The population dynamics of gfp-labeled P. pseudoalcaligenes KF707 in PCB contaminated environment was examined with or without terpenoids added in microcosm, We found about 10-100 folds increase in population of PCB degraders with added terpenoids compared with control (non-terpcnoids samples and biphenyl added samples). We proposed that gfr-monitoring system is very useful and terpenoids enhance the survivability of PCB degraders in PCB contaminated environment.

다국어 초록 (Multilingual Abstract)

Polychlorinated biphenyls (PCBs) are toxic pollutants and their degradation is quite slow in the environment. Recently, interests in bioremediation using PCB-degrading bacteria have increased.
Terpenes are natural substrates with structural similarities to PCB. They also have been known to be widely present in the environment and relatively non-toxic to human. In a previous report, plant terpenes (p-cymene, (S)-(-)-limonene, a-pynene, and a-terpinene) have been found to be utilized by a PCB degrader and to induce bph (biphenyl dioxygenase) gene in pure culture. Therefore it has been proposed that using terpenes rather than PUB congeners is very useful to stimulate PCB degradation. In this study, Pseudomonas pseudoalcaligenes KF707, a PCB-degrading Gram-negative soil bacterium was used to determine whether the terpenoid stimulation of PCB degrader occurs in natural environment. First, P. pseudoalcaligenes KF707 was genetically tagged using transposon with gfp (green fluorescent protein) as a reporter gene. The population dynamics of gfp-labeled P. pseudoalcaligenes KF707 in PCB contaminated environment was examined with or without terpenoids added in microcosm, We found about 10-100 folds increase in population of PCB degraders with added terpenoids compared with control (non-terpcnoids samples and biphenyl added samples). We proposed that gfr-monitoring system is very useful and terpenoids enhance the survivability of PCB degraders in PCB contaminated environment.

목차 (Table of Contents)

• ABSTRACT = I
• CONTENTS = III
• LIST OF TABLES = V
• LIST OF FIGURES = VI
• LIST OF ABBREVIATIONS = VIII
• 1. INTRODUCTION = 1
• 1.1. Polychlorinated biphenyl (PCB) = 1
• 1.2. Bioremediation = 4
• 1.3. Bioaugmentation and biostimulation = 8
• 1.4. Plant terpenoid = 11
• 1.5. Green fluorescent protein (GFP) = 13
• 2. MATERIALS AND METHODS = 17
• 2.1. Bacterial strains and chemicals = 17
• 2.2. Electrotransformation and selection of useful gfp mutants = 21
• 2.3. Southern blot analysis = 22
• 2.4. Plasmid stability = 23
• 2.5. Utilization test of terpenoids = 24
• 2.6. Microcosm study = 24
• 3. RESULTS AND DISCUSSION = 27
• 4. REFERENCES = 42
• 5. ACKNOWLEDGEMENT = 48