전분분해활성과 알코올 발효능을 보유한 효모의 육종

Breeding of Yeast Strain with Starch Utilizing and Alcohol Fermenting Ability by Protoplast Fusion

  • 발행 : 2008.06.28

초록

Saccharomyces diastaticus KCTC 1804 균주와 Saccharomyces cerevisiae KOY-1 균주를 이용하여 전분분해활성과 알코올 발효능을 동시에 가지는 효모융합체를 개발하였다. Saccharomyces cerevisiae KOY-1 균주의 단수체 유도를 통하여 Saccharomyces cerevisiae KH-12 균주를 획득하였다. EMS를 사용한 돌연변이 유발을 통하여 Saccharomyces cerevisiae KH-12 균주의 Met 영양요구성 변이주를 획득하였다. Lyticase 처리로 Saccharomyces cerevisiae KOY-1 $(Met^-)$, Saccharomyces diastaticus KCTC 1804$(Trp^-)$ 균주의 원형질체 형성률은 각각 90.5%, 97.7%로 관찰되었다. 원형질체 융합은 polyethylene glycol 4,000을 이용하여 실시하였고, 이때 원형질체 융합율은 $1.79{\times}10^{-4}$으로 관찰되었다. 원형질체융합과정을 통해 총 1,000주의 융합체를 획득하였고, 획득한 융합체의 전분분해능과 알코올발효능을 비교하여 최종적으로 전분배지 YPS24에서 알코올생성능이 가장 우수한 효모융합체인 FA 776을 최종 선발하였다 최종 선발된 효모융합체 FA 776은 10세대 계대배양 후의 revertent 복귀율이 4.64%로 유전적 안정성을 확인하였으며, 효모융합체의 total DNA 함량을 비교한 결과, Saccharomyces cerevisiae 균주로부터 분리된 단수체 효모 KH-12는 26.56 fg/cell, Saccharomyces diastaticus KCTC 1804 균주는 25.40 fg/cell이었고, 이들을 사용해서 얻어진 융합체 FA 776의 DNA함량은 42.67 fg/cell이었다. 전분배지 YPS24배지에서 60시간 발효하였을때 Saccharomyces cerevisiae KOY-1 균주는 알코올 생성하지 못하였지만 효모융합체 FA 776은 13 mg/mL의 알코올을 생성하였다. 이는 전분이용성 효모인 Saccharomyces diastaticus KCTC 1804 균주에 비해 1.86배나 향상된 알코올 발효능을 나타냈다.

The fusants which contain starch utilizing ability and alcohol fermenting ability were developed by protoplast fusion of Saccharomyces cerevisiae KOY-1 and Saccharomyces diastaticus KCTC 1804. Sacharomyces cerevisiae KH-12 was obtained by haploid induction from Saccharomyces cerevisiae KOY-1. The auxotropic mutants of yeast were obtained by using an ethylmethane sulfonate (EMS). The frequency of protoplast formation in Saccharomyces cerevisiae KOY-1 $(Met^-)$ and Saccharomyces diastaticus KCTC 1804 $(Trp^-)$ were 90.5% and 97.7%, respectively. The frequency of fusant formation was $1.79{\times}10^{-4 }$ for the regenerated protoplast and the 1,000 fusants were obtained. Fusant FA 776 was selected as a potential yeast which contain an alcohol fermenting ability in the starch medium. The genetic stability was 4.64% for 10 passages of generation. Fusant FA 776 produced 13mg/ml of alcohol in 24% starch medium and showed 1.86-fold higher alcohol fermenting ability than Saccharomyces diastaticus KCTC 1804.

키워드

참고문헌

  1. Anna, K. K. 1990. Yeast and Yeast-like Organisms, pp. 131- 205. 1st ed. VCH Press, New York, U.S.A.
  2. Amberg, D. C. 2005. Methods in yeast genetics. A cold spring harbor laboratory press. pp. 11-19
  3. Amberg, D. C. 2005. Methods in yeast genetics. A cold spring harbor laboratory press. pp. 143
  4. Calleja, G. B. 1987. Cell aggregation. Academic press INC., pp. 180-183
  5. Jeong, J. W. 2006. Characterization of antioxidant property of Korean alcoholic liquors. Food Engineering Progress. 10: 221-225
  6. Kim, J. H., S. C. Jeong, N. M. Kim, and J. S. Lee. 2003. Effect of indian millet Koji and legumes on the quality and angiotensin I-converting enzyme inhibitory activity of Korean traditional rice wine. Korean J. Food. Sci. Technol. 35: 733-737
  7. Kim, J. S., S. H. Ko, W. Y. Lee, and G. W. Kim. 2004. Cytotoxic effects of Korean rice-wine on cancer cells. Korean J. Food Sci. Technol. 36: 812-817
  8. Kim, K. 2001. The use of respiratory-deficient mutation and heat inactivation for the selection of yeast protoplast fusants. J. Natural Science. The Univ. of Suwon Univ. 4: 103-115
  9. Kim, K. K. 2003. Rice wine making by using yeasts from Korean traditional Nuruk. M.S. thesis Korea Univ.
  10. Kuk, S. J. 2003. Studies on the preparation of traditional ginseng wine added with different pretreated ginseng. M.S. thesis Hankyng Univ.
  11. Kim, T. W. 2001. Quality assessment of traditional wine by lumitester. M.S. thesis Kyng San Univ.
  12. Lee, S. M. 1992. Study of breeding yeast by cell fusion. Anseong Agricultural Jr. college 24: 231-235
  13. Lee, T. S. and C. S. Park. 2002. Quality characteristics of Takju prepared by wheat flour Nuruks. Korean J. Food. Sci. Technol. 34: 296-302
  14. Park, I. B., B. S. Park, and S. T. Chung. 2003. Brewing and functional characteristics of HongkukJu prepared with various Hongkuks. Korean J. Food. Sci. Technol. 35: 943- 950
  15. Shin, C. S., S. K. Lee, and Y. J. Park. 1996. Selection of koji and yeast strain for improvement of Choungju quality. Agri. Chem. Bio. 29: 16-19
  16. So, M. H., Y. S. Lee, and W. S. Noh. 1999. Changes in microorganisms and main components during Takju brewing by a modified Nuruk. Korean J. Food & Nutr. 12: 226-232
  17. Tsuyoshi, N., R. Fudou, S. Yamanaka, M. Kozaki, N. Tamang, S. Tapha, and J. P. Tamang. 2005. Identification of yeast strains isolated from marcha in sikkim, a microbial starter for amylolytic fermentation. Int. J. Food Microbiol. 99: 135-146 https://doi.org/10.1016/j.ijfoodmicro.2004.08.011
  18. Wilson, J. J., G. G. Khachatourians, and W. M. Ingledew. 1982. Protoplast fusion in the yeast, Schwanniomyces alluvius. Molec. Gen. Genet., 186: 95-106 https://doi.org/10.1007/BF00422918
  19. Yamamura, M. 1975. Preparation of protoplasts of hydrocarbon- utilizing yeast cells and their reporatoru activities. Agric. Biol. Chem. 39: 13-20 https://doi.org/10.1271/bbb1961.39.13