Isolation from Chungkookjang and Characterization of a Bacterium Producing an Extracellular Protease of High Specific Activity

청국장으로부터 고 비활성 세포외 Protease 생산 세균의 분리 및 동정

  • 박희진 (경북대학교 식품공학과) ;
  • 박희동 (경북대학교 식품공학과)
  • Received : 2009.12.16
  • Accepted : 2010.05.28
  • Published : 2010.06.30

Abstract

Several extracellular protease-producing bacteria were isolated from Chungkookjang, a traditional Korean food of fermented soybeans, on skim milk agar plates. Among these bacteria, strain D14 exhibited the highest production (15.2 U/mL) and specific activity (40.0 U/mg protein) of extracellular protease activity as assessed on growth in a protease induction medium composed of 1% (w/v) soluble starch, 1.5% (w/v) skim milk, 0.5% (w/v) yeast extract, and 2% (w/v) NaCl. The bacterium was identified as Bacillus subtilis based on morphological and physiological characteristics and 16S rDNA sequence. A BLAST search of 16S rDNA sequences revealed that the isolate was most closely related to Bacillus subtilis subsp. subtilis strain NCIB 3610. The 16S rDNA sequence homology was 99.9%. Our isolate produced the highest level of protease when grown in a protease induction medium containing 1% (w/v) sorbitol and 0.5% (w/v) yeast extract. Fructose and glucose reduced enzyme production to 12.7% and 35.9%, respectively, of the level seen when the strain was grown in medium containing soluble starch. Soytone also reduced enzyme production to 61.4% of the level noted when the strain was grown in medium containing yeast extract.

우리나라 전통발효식품의 하나인 청국장으로부터 고 비활성 세포외 protease 생산능이 우수한 균주를 분리하고 그 특성을 조사하였다. 분리된 균주 중 D14 균주 배양 상징액의 protease 활성이 15.2 U/mL로서 가장 강하였으며 비활성 또한 40.0 U/mg protein으로서 가장 강하게 나타났다. 이 균주의 특성을 조사한 후 Berge's Manual of Systematic Bacteriology에 준하여 Bacillus subtilis로 동정하였다. 균주 D14의 16S rDNA 염기서열을 분석하여 B. subtilis subsp. subtilis NCIB 3610 균주와 99.9%의 상동성을 가짐을 확인 하였다. 또한 16S rDNA의 염기서열을 토대로 계통분석을 통하여 다른 Bacillus sp.의 균주들보다 NCIB 3610 균주와 유전적으로 매우 가까운 관계에 있음을 확인하였다. Soluble starch는 사용한 탄소원 중 가장 높은 수준의 protease 생산능을 보였으나 단당류, 이당류 등은 모두 효소 생산능에 대하여 저해효과를 나타내었다. 특히 fructose를 첨가한 경우에는 12.7%, glucose를 첨가한 경우에는 35.9% 수준의 효소 생산능을 나타내었다. 질소원의 경우는 soytone의 첨가구에서 대조구에 비하여 약 61.4% 수준의 효소활성을 나타내어 저해효과가 가장 높았으며 다른 질소원은 효소 생산에 크게 영향을 미치지 않았다.

Keywords

References

  1. National Rural Living Science Institute, R.D.A. (1996) Food Composition Table, 5, 324-325
  2. Kim, S.Y. and Kim, W.U. (1967) Studies on the changes of protein, peptide and amino acid during preparation. Korean J. Agric. Chem., 8, 11-20
  3. Kim, J.G., Kim, S.K. and Lee, J.S. (1988) Fatty acid composition and electrophoretic patterns of protein of Korean soy beans. Korean J. Food Sci. Technol., 20, 263-271
  4. Landers, R.E. and Rathmann, D.M. (1981) Vegetable oils: Effect of processing storage and use on nutritional values. J. Am. Oil Chem., 58, 255-259 https://doi.org/10.1007/BF02582352
  5. Onishi, R., Keiko, A., Seiichi, H. and Ko, A. (1987) Studies on a viscous substance of the natto. Nippon Kasei Gakkaishi., 10, 871-875
  6. Lee, Y.L., Kim, S.H., Choung, N.H. and Yim, M.H. (1992) A study on the production of viscous substance during Chungkookjang fermentation J. Korean Soc. Agric. Chem. Soc., 35, 202-209
  7. Ashiuchi, M., Kamei, T., Baek, D.H., Shin, S.Y., Sung, M.H., Soda, K. Yagi, T. and Misono, H. (2001) Isolation of Bacillus subtilis (chungkookjang), a poly-gammaglutamate producer with high genetic competence. Appl. Microbiol. Biotechnol., 57, 764-769 https://doi.org/10.1007/s00253-001-0848-9
  8. Lee, B.Y., Kim, D.M. and Kim, K.H. (1991) Physico-chemical properties of viscous substance extracted from Chungkookjang. Korean J. Food Sci. Technol., 23, 500-506
  9. Lee, J.O., Ha, S.D., Kim, A.J., Yuh, C.S., Bang, I.S. and Park, S.H. (2005) Industrial application and physiological function of Chongkukjang. Food Sci. Ind., 38, 69-78
  10. Heo, S., Lee S.K. and Joo H.K. (1998) Isolation and identification of fibrinolythic bacteria from Korean traditional Chungkookjang. Agric. Chem. Biotechnol., 41, 119-124
  11. Kim, W.K., Choi, K.H., Kim, Y.T., Park, H.H., Choi, J.Y., Lee, Y.S., OH, H.I., Kwon, I.B. and Lee, S.Y. (1996) Purification and characterization of fibrinolytic enzyme produced from Bacillus sp. strains CK11-4 screened from chungkookjang. Appl. Environ. Microbiol., 62, 2482-2488
  12. Kim, N.Y., Song, E.J., Kwon, D.Y., Kim, H.P. and Heo, M.Y. (2008) Antioxidant and antigenotoxic activities of Korean fermented soybean. Food Chem. Toxicol., 46, 1184-1189 https://doi.org/10.1016/j.fct.2007.12.003
  13. Yoon, K.D., Kwon, D.J., Hong, S.S., Kim, S.I. and Chung, K.S. (1996) Inhibitory effect of soybean and fermented soybean products on the chemically induced mutagenesis. Korean J. Appl. Microbiol. Biotechnol., 24, 525-528
  14. Choi, Y.H., Lim, H., Heo, M.Y., Kwon, D.Y. and Kim, H.P. (2008) Anti-inflammatory activity of the ethanol extract of Chungkukjang, Korean fermented bean: 5-lipoxygenase inhibition. J. Med. Food, 11, 539-543 https://doi.org/10.1089/jmf.2007.0125
  15. Kim, D.J., Jeong, Y.J., Kwon, J.H., Moon, K.D., Kim, H.J., Jeon, S.M., Lee, M.K., Park, Y.B. and Choi, M.S. (2008) Beneficial effect of chungkukjang on regulating blood glucose and pancreatic beta-cell functions in C75BL/KsJ-db/db mice. J. Med. Food, 1, 215-223
  16. Kwon, D.Y., Daily, J.W. 3rd, Kim, H.J. and Park, S. (2010) Antidiabetic effects of fermented soybean products on type 2 diabetes. Nutr. Res., 30, 1-13 https://doi.org/10.1016/j.nutres.2009.11.004
  17. Kim, J.I., Kang, M.J. and Kwon, T.W. (2003) Antidiabetic effects of soybean and chungkookjang. Korean Soybean Digest., 20, 44-52
  18. Yang, J.L., Lee, S.H. and Song, Y.S. (2003) Improving effect of powders of cooked soybean and chungkookjang on blood pressure and lipid metabolism in spontaneously hypertensive rats. J. Korean Soc. Food. Sci. Nutr., 32, 899-905 https://doi.org/10.3746/jkfn.2003.32.6.899
  19. Choi, Y.B. and Sohn, H.S. (1998) Isoflavone content in Korean fermented and unfermented soybean foods. Korean J. Food Sci. Technol., 30, 745-750
  20. Naim, M., Gestetner, B., Bond, A. and Birk, Y. (1976) Antioxidative and antihemolytic activity of soybean isoflavones. J. Agric. Food Chem., 22, 806-810
  21. Messina, M. and Messina, V. (1991) Increasing use of soyfoods and their potential role in cancer prevention. J. Am. Diet Assoc., 91, 836-841
  22. Youn, K.C., Kim, D.H., Kim, J.O., Park, B.J., Yook, H.S., Cho, J.M. and Byun, M.W. (2002) Quality characteristics of the chungkookjang fermented by the mixed culture of Bacillus natto and B. licheniformis. J. Korean Soc. Food Sci. Nutr., 31, 204-210 https://doi.org/10.3746/jkfn.2002.31.2.204
  23. Lee, O.K., Ha, S.D., Kim, A.J., Yuh, C.S., Bang, I.S. and Park, S.H. (2005) Industrial application and physiological functions of Chongkukjang. Food Sci. Ind., 38, 69-78
  24. Godfrey, T. and Reichelt, J. (1983) Industrial enzymology : The application of enzyme in industry. The Nature's Press Co., Mercer, U.S.A., pp127-172
  25. Peckman, E.V. (1951) Aspergillus protease. Biochemistry, 5, 321-325
  26. Masaaki, Y., Kazuo, S. and Mitsuo, M. (1984) Purification and properties of acid protease from Monascus sp. No. 3405. Agric. Biol. Chem., 48, 1637-1645 https://doi.org/10.1271/bbb1961.48.1637
  27. Kageyama, K. (1955) Studies on Aspergillus oryzae strain for sake brewing. J. Ferment. Technol., 33, 53-57
  28. Nunokawa, Y., Namba, Y. and Watanabe, S. (1961) A study of the rice Koji protease. J. Soc. Brew., 53, 930-933
  29. Kang, S.M., Cha, M.K., Kim, S.J. and Kwon, Y.J. (2006) The effect of quality improvement for wool and silk treated with protease produced by B. subtilis K-54. J. Korean Soc. Cloth. Ind., 8, 239-244
  30. Bruckner, R., Shoseyov, O. and Doi, R.H. (1990) Multiple active forms of a novel serine protease from B. subtilis. Mol. Gen. Genet., 221, 486-490
  31. Molière, N. and Turgay, K. (2009) Chaperone-protease systems in regulation and protein quality control in Bacillus subtilis. Res. Microbiol., 160, 637-644 https://doi.org/10.1016/j.resmic.2009.08.020
  32. Park, C.S., Min, D.K., Ahn, Y.S., Lee, J.H., Hong, S.K., Kim, J.H. and Kang, D.K. (2002) Isolation and characteristics of soy protein-degrading strain, Bacillus subtilis EB464. Korean J. Microbiol. Biotechnol., 30, 210-215
  33. Ahn, Y.S., Kim, Y.S. and Shin, D.H. (2006) Isolation, identification and fermentation characteristics of Bacillus sp. with high protease activity from traditional Cheonggukjang. Korean J. Food Sci. Technol., 38, 82-87
  34. Kim, D.Y., Lee, E.T. and Kim, S.D. (2003) Purification and characterization of fibrinolytic enzyme produced by Bacillus subtilis K7 isolated from Korean traditional soy sauce. J. Korean Soc. Agric. Chem. Biotechnol., 46, 176-182
  35. Kim, K.P., Kim, N.H., Lee, C.H., Woo, C.J. and Bae, D.H. (2002) Isolation and characterization of protease producing bacteria from soil. J. Korean Soc. Food Sci. Nutr., 31, 754-759 https://doi.org/10.3746/jkfn.2002.31.5.754
  36. Cha, Y.J., Lee, K.H. and Chang, D.S. (1988) Characterization of the strong proteolytic bacteria isolated from low salt fermented anchovy and of protease produced by that strain. Bull. Korean Fish. Soc., 21, 71-79
  37. Jung, H.K., Jeong, Y.S., Youn, K.S., Kim, D.I. and Hong, J.H. (2009) Quality characteristics of soybean paste (Doejang) prepared with Bacillus subtilis DH3 expressing high protease levels and deep-sea water. Korean J. Food Preserv., 16, 348-354
  38. Jung, S.T., Kim, M.H., Shin, D.H. and Kim, Y.S. (2008) Isolation and identification of Bacillus sp. with high protease and amylase activity from Sunchang traditional Kochujang. Food Sci. Biotechnol., 17, 519-526
  39. Murray, R.G.E., Brenner, D.J., Bryant, M.P., Holt, J.G., Kreig, N.R., Moulder, J.W., Pfenning, N., Sneath, P.H.A. and Staley, J.T. (1986) Bergey's Mannual of Systematic Bacteriology, 2, 1104-1139
  40. Sheehan, D. and Hrapchak, B. (1980) Theory and practice of histotechnology. Battelle Press, Columbus, U.S.A., pp.330-331
  41. Knutton, S. (1995) Electron microscopical methods in adhesion. Method. Enzymol., 253, 145-158 https://doi.org/10.1016/S0076-6879(95)53015-0
  42. Hayashi, H., Sakamoto, M. and Benno, Y. (2004) Evaluation of three different forward primers by terminal restriction fragment length polymorphism analysis for determination of fecal Bifidobacterium spp. in health subjects. Microbiol. Immunol., 48, 1-6
  43. Sambrook, J. and Russell, D.W. (2001) Molecular cloning, a laboratory manual, 3rd ed. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, U.S.A., p.8.18-8.24
  44. Bradford, M.M. (1964) A rapid and sensitive method for the quantitation of microorganism quantities of protein utilizing the principle of protein-dye binding. Anal.Biochem. 72, 248-254
  45. Hull, M.E. (1974) Studies on milk proteins II. Colorimetric determination of the partial hydrolysis of the proteins in milk. J. Dairy Sci., 30, 881-884