Isolation and Characterization of Mesophilic Luminescent Bacteria 作者:柯明喬、賴文彬 指導老師:趙維良老師
Luminescent bacteria Luminescent bacteria = Luminous bacteria Characterization Visible Light → Aerobic Large cell density Morphology → G (-), short rod, flagella
Light production Luciferase FMNH2 + O2 + RCHO FMN + RCOOH + H2O + LIGHT Luciferase
Luminescent bacteria Ecology Genus: Saprophyte, parasite, symbiosis, free-living Genus: Marine: Vibrio, Photobacterium, Aeromonas Land: Xenorhabdus
表一、 Vibrio, Photobacterium, Aeromonas 之特性差異 Genus Characteristics Accumulation of β-hydroxybutyrate Utilization of mannitol Vibrio - + Photobacterium Aeromonas + 正反應或有生長。 - 負反應或無生長。
Accumulation of β-hydroxybutyrat + -
Mesophilic bacteria Growth temperature range: 15 – 45 ℃ Optimum growth temperature: 25 ℃
Materials and method procedure Collection Culture Isolation Sampling: sea-fish skin (S) & enteron (E) Culture Medium: modified MSWYE, luminous medium Condition: 25℃, aerobic, Isolation Streak plate method Identification Morphology observation Use of mannitol Accumulation of β-hydroxbutyrate
Sample 2 Sample 1 Sample 3 Sample 4
Sampling
Medium Luminous medium (per Liter) NaCl 30 g NH4Cl 5 g Yeast extract 5 g CaCO3 1 g Glycerol 3 ml Pancreatic digest of casein 5 g K2HPO4 3.9 g KH2PO4 2.1 g MgSO4‧7H2O 1 g KCl 0.75 g 1 M Tris buffer (pH 7.5) 50 ml Agar 20 g
Modified MSWYE (per Liter) Medium Modified MSWYE (per Liter) NaCl 23.4 g MgSO4‧7H2O 6.98 g KCl 0.75 g Protease peptone 1 g Yeast extract 1 g Agar 20 g Use NaOH (1N) adjust to pH 7.6
Medium Basal medium (per Liter) NaCl 23.4 g MgSO4‧7H2O 24.6 g KCl 1.5 g CaCl2‧2H2O 2.9 g Artificial sea water (per Liter) 500 ml MgSO4‧7H2O 24.6 g CaCl2‧2H2O 2.9 g
Results 10 isolates 2EL 3EL1 3EL3D 3EL3S 3EM1D 3EM2D 3EM2S 3EM3 4EL 4SL
2EL
3EL1
3EL3D
3EL3S
3EM1D
3EM2D
3EM2S
4EL
4SL
表二、分離株生化測試結果表 。 分離株名稱 生長溫度 (℃) 利用 mannitol 聚集 β-hydroxybutyrate 可能分類 4 25 55 2EL - + Vibrio 3EL1 Photobacterium 3EL3D 3EL3S Aeromonas 3EM1D ND 3EM2D 3EM2S 3EM3 4EL 4SL + 正反應或有生長。 - 負反應或無生長。 ND 無法判斷。 生長溫度測試以 luminous medium 平板培養 2 天。 Mannitol 利用以 basal medium 加入 0.2% mannitol 培養。 β-hydroxybutyrate 累積實驗以 basal medium 加入 0.2% glucose 培養。 除溫度測試外,所有測試皆以 25℃ 培養 2 天後觀察。
3EM2S (Photobacterium sp.) 表三、分離株在不同培養基上亮度差異 LM mMSWYE 2EL (Vibrio sp.) + - 3EL3S (Aeromonas sp.) 3EM2S (Photobacterium sp.) 3EM3 (ND) 4EL (Aeromonas sp.) 4SL (Aeromonas sp.) + 發亮。 - 不發亮。 ND 無法判斷。
Discussion 不同樣本分離得發光菌多樣性不同 樣本表皮與腸道分離得發光菌多樣性不同 同一菌株在不同培養基上發亮情形不同 樣本生活環境 採樣時間距離樣本上岸時間太長 表皮與腸道溫度差異 同一菌株在不同培養基上發亮情形不同 培養基成分
References Hendrie, M. S., W. Hodgkiss, and J. M. Shewan. 1970. The indentification, taxonomy and classification of luminous bacteria. J. Gen. Microbiol. 64: 151-169. Schwarz, J. R., and R. R. Colwell. 1974. Effect of hydrostatic pressure on growth and viablity of Vubrio parahaemolyticus. Appl. Microbiol. 26: 977-981 Nealson, K. H. 1978. Isolation, indentification and manipulation of luminous bacteria. Methods Enzymol. 57: 153-166
References Orndorff, S. A., and R. R. Colwell. 1980. Distribution and identification of luminous bacteria from the Sargasso. Appl. Environ. Microbiol. 39: 983-987 PE-BEE: WORLD: http://soils1.cses.vt.edu/ch/biol_4684/Microbes/Photo.html 發光菌簡介:http://science.scu.edu.tw/micro/1024/learn/02micro_bio/chao000/chao016.htm