Cloning of the Cellulase Gene and Characterization of the Enzyme from a Plant Growth Promoting Rhizobacterium, Bacillus licheniformis K11

고추역병 방제능이 있는 식물성장촉진 균주 Bacillus licheniformis K11의 cellulase 유전자의 cloning 및 효소 특성 조사

  • Woo, Sang-Min (Department of Applied Microbiology, Yeungnam University) ;
  • Kim, Sang-Dal (Department of Applied Microbiology, Yeungnam University)
  • 우상민 (영남대학교 응용미생물학과) ;
  • 김상달 (영남대학교 응용미생물학과)
  • Published : 2007.06.30

Abstract

The cellulase gene of Bacillus licheniformis K11 which has plant growth-promoting activity by auxin and antagonistic ability by siderophore was cloned in pUC18 using PCR employing heterologous primers. The 1.6kb PCR fragment contained the full sequence of the cellulase gene, denoted celW which has been reported to encode a 499 amino acid protein. Similarity search in protein data base revealed that the cellulase from B. licheniformis K11 was more than 97% identical in amino acid sequence to those of various Bacillus spp. The cellulase protein from B. licheniformis K11, overproduced in E. coli DH5${\alpha}$ by the lac promoter on the vector, had apparent molecular weight of 55 kDa upon CMC-SDS-PAGE analysis. The protein not only had enzymatic activity toward carboxymethyl-cellulose (CMC), but also was able to degrade insoluble cellulose, such as Avicel and filter paper (Whatman$^{\circledR}$ No. 1). In addition, the cellulase could degrade a fungal cell wall of Phytophthora capsici. Consequently B. licheniformis K11 was able to suppress the peperblight causing P. capsici by its cellulase. Biochemical analysis showed that the enzyme had a maximum activity at 60$^{\circ}C$ and pH 6.0. Also, the enzyme activity was activated by Co$^{2+}$ of Mn$^{2+}$ but inhibited by Fe$^{3+}$ or Hg$^{2+}$. Moreover, enzyme activity was not inhibited by SDS or sodium azide.

식물성장 촉진호르몬인 auxin, 식물병원성 진균을 방제하는 siderophore 그리고 cellulase를 동시에 생산하는 PGPR균이자 생물방제균인 Bacillus licheniformis K11의 cellulase의 유전자를 PCR을 이용해 pUC18에 재조합 후 E. coli DH5${\alpha}$에 cloning하였으며, 이 형질전환 된 균주를 E. coli DH5${\alpha}$(pCW 77)라 하였다. 형질전환 균주 E. coli DH5${\alpha}$(pCW 77)는 B. licheniformis K11의 1.6kb 유전자를 포함하며, 이 cellulase는 1,479 bp, 499개의 amino acid가 암호화된 것으로 추정된다. 형질전환균주가 생산하는 cellulase(CelW)는 lac 프로모터를 이용해 발현되었으며, CMC-SDS-PAGE의 방법으로 약 55 kDa의 분자량을 확인하였다. B. licheniformis K11의 cellulase는 4종의 대표적인 Bacillus spp. 들이 생산하는 cellulase의 아미노산 배열이 97% 이상 일치하였다. CelW는 carboxymethyl-cellulose(CMC) 뿐만 아니라 불용성 섬유소인 Avicel, Filter paper(Whatman$^{\circledR}$ No. 1)는 물론이고 고추역병균 P. capsici의 건조 cell wall도 분해하였다. CMC를 기질로 60$^{\circ}C$에서 효소활성이 가장 높았으며, 최적 pH는 pH 6.0이었다. 그리고 CoCl$_2$ 또는 MnSO$_4$ 첨가시 활성이 2배 이상 증가하였지만, FeCl$_3$ 또는 HgCl$_2$ 첨가 시는 활성이 20% 이하로 떨어졌고, SDS와 sodium azide 등 여러 화학 저해제들을 첨가하여도 87% 이상의 활성을 유지하였다. 이 결과들은 B. licheniformis K11이 식물뿌리에 근권 microflora형성의 중요한 요인으로 작용할 수 있고, 생물방제력을 발휘하는 식물병원성 진균의 세포벽 분해 cellulase 기능 연구를 가능케 하여 식물병의 생물학적 방제 연구에 기초가 될 것이라 생각된다.

Keywords

References

  1. Beguin, P. and Aubert, J. P. (1994) The biological degradation of cellulase. FEMS Microbiol. Rev. 13, 25-58 https://doi.org/10.1111/j.1574-6976.1994.tb00033.x
  2. Bisaria, V. S. and Ghose, T. K. (1981) Biodegradation of cellulosic materials : substrate, microorganisms, exzymes and products. Enz. microbiol. technol. 3, 90-104 https://doi.org/10.1016/0141-0229(81)90066-1
  3. Tomme. P., Warren, R. A. J. and Gilkes, N. R. (1995) Cellulose hydrolysis by bacteria and fungi. Adv. Microb. Physoil. 37, 1- 81 https://doi.org/10.1016/S0065-2911(08)60143-5
  4. Woo, S. M., Jung, H. K. and Kim, S. D. (2006) Cloning and characterization of a cellulase gene from a plant growth promoting rhizobacterium, Bacillus subtilis AH18 against phytophthora blight disease in red-pepper. Kor. J. Microbiol. Biotechnol. 34, 311-317
  5. Lim, S. T., Park, Y. Y., Cho, S. J. and Yun, H. D. (1997) Phytopathgenicity of Erwinia carotovora subsp. carotovora LY34 and production of CMCase isozymes. Kor. J. Appl. Microbiol. Biotechnol. 25, 468-476
  6. Kumar, R., Dahiya, J. S., Singh, D. and Nigam, P. (2000) Production of endo-1,4-${\beta}$-glucanase by a biocontrol fungus Cladorrhinum foecundissimu. Bioresource. Technol. 75, 95-97 https://doi.org/10.1016/S0960-8524(00)00037-7
  7. Saddler, J. N. (1993) Bioconversion of forest and agricultural plant residues. C. A. B. International, Oxford
  8. Gilbert, H. J. and Hazlewood, G. P. (1993) Bacterial cellulase and xylanases. J. Gen. Microbiol. 139, 187-194 https://doi.org/10.1099/00221287-139-2-187
  9. Chung, Y. C., Kim, Y. W., Kang, S. K., Rho, J. S., Park, J. H. and Sung, N. K. (1991) Cloning of thermophilic alkalophilic Bacillus sp. F204 cellulase gene and its expression in Escherichia coli and Bacillus subtilis. Kor. J. Food.. Sci. Technol. 23, 31-36
  10. Hong, I. P., Jang, H. K., Lee, S. Y. and Choi, S. G. (2003) Cloning and characterization of a bifunctional cellulasechitosanase gene from Bacillus licheniformis NBL420. J. Microbiol. Biotechnol. 13, 35-42
  11. Her, S., Kim, D. S., Choi, S. J. and Oh., D. H. (1993) Cloning and DNA sequence of carboxymethylcellulase(CMCase) gene from Cellulomonas sp. YE-5. J. Microbiol. Biotechnol. 3, 86- 90
  12. Lee, J. K., Yoon, K. H., Kim, B. H., Kwon, G. S. and Kim, S. B. (1992) Cloning and expression in Escherichia coli of cellulase genes from a mesophilic Clostridium sp. J. Microbiol. Biotechnol. 2, 50-55
  13. Lim, W. J., Ryu, S. K., Park, S. R., Kim, M. K., An, C. L., Hong, S. Y., Shin, E. C., Lee, J. Y., Lim, Y. P. and Yun., H. D. (2005) Cloning of celC, third cellulase gene, from Pectobacterium carotovorum subsp. carotovorum LY34 and its comparison to those of Pectobacterium sp. J. Microbiol. Biotechnol. 15, 302-309
  14. Park, Y. W., Lim, S. T., Kang, K. Y. and Yun, H. D. (1995) Cloning of CM - cellulase gene of Rhizobium meliloti TAL1372 in Escherichia coli. J. Kor. Agr. Chem. Soc. 38, 313- 319
  15. Jung, H. K., Kim, J. R., Woo, S. M. and Kim, S. D. (2007) Selection of the auxin, siderophore, and cellulase-producing PGPR, Bacillus licheniformis K11 and its plant growth promoting mechanisms. J. Kor. Soc. Appl. Biol. Chem. 50, 23- 28
  16. Kunst F., Ogasawara, N., Moszer, I., Albertini, A. M., Alloni, G., Azevedo, V., Bertero, M. G., et al. (1997) The complete genome sequence of the gram-positive bacterium Bacillus subtilis. Nature. 390, 249-256 https://doi.org/10.1038/36786
  17. Sambrook, J. and Russell, D. W. (2001) Molecular cloning: a laboratory manual, Vol. 1, 2, 3. (3th ed.) Cold Spring Harbor. New York
  18. Teather, R. and Wood, P. J. (1982) Use of congo redpolysaccharide interactions in enumeration and characterization of cellulolytic bacteria from the bovine rumen. Appl. Environ. Microbiol. 43, 777-780
  19. Miller, G. L (1959) Use of dinitrosalicylic acid reagent for determination of reducing sugar. Anal. Chem. 31, 426-428 https://doi.org/10.1021/ac60147a030
  20. Lim, S. T., Park, Y. Y., Cho, S. J. and Jun, H. D. (1997) Phytopathogenicity of erwinia carotovora subsp. carotovora LY34 and procuction of CMCase isozymes. Kor. J. Appl. Microbiol. Biotechnol. 25, 468-476
  21. Kim, J. H., Lee, J. C., Lee, Y. K., Kim, K. H., Chun, S. B. and Chung, K. C. (1993) Purification and chracterization of carboxymethyl cellulase IV from Penicillium verruculosm. Kor. J. Mycology 21, 28-37
  22. Yoo, K. H. and Chang, H. S. (2002) Purification and chracterization of carboxymethyl cellulase from Stropharia rugosoannulata. Kor. J. Mycology 30, 113-118 https://doi.org/10.4489/KJM.2002.30.2.113
  23. Kim, J. H., Lee, J. C., Lee, Y. K., Kim, K. H., Chun, S. B. and Chung. K. C. (1993) Purification and chracterization of carboxymethyl cellulase IV from Penicillium verruculosm. Kor. J. Mycology 21, 28-37
  24. Sul, O. J., Chung, D. K., Han, I. S. and Jeong, C. S. (2005) Chracterization of Endoglucanase (F-I-III) Purified from Trichoderma sp. C-4. Kor. J. Microbiol. 41, 81-86