화학수식제에 의한 Bacillus alcalophilus AX2000 유래 Xylanase의 활성에 관여하는 아미노산 잔기의 확인

Identification of Amino Acid Residues Involved in Xylanase Activity from Bacillus alcalophilus AX2000 by Chemical Modifiers

  • 박영서 (경원대학교 생명공학부)
  • 발행 : 2006.06.01

초록

Bacillus alcalophilus AX2000으로부터 xylanase를 정제한 후 효소의 활성부위를 조사하기 위하여 여러 가지 화학수식제를 사용하여 효소활성의 저해도를 측정하였다. 여러 가지 화학 수식제 중에서 carbodiimide와 N-bromosuccinimide가 효소 활성을 완전히 저해시켜 glutamic acid또는 aspartic acid 잔기와 tryptophan 잔기가 효소의 활성부위에 관여하리라 추측되었다. 각각의 경우에 효소 실활은 수식제의 첨가농도에 따라 pseudo first-order kinetics 양식을 보여주었으며, carbodiimide와 N-bromosuccinimide는 각각 비경쟁적 저해와 경쟁적 저해방식을 나타내었다. 기질첨가에 의한 효소활성 보호실험을 통하여 tryptophan 잔기가 기질결합부위라 판단 되었다. 효소 실활속도의 분석에 의해 효소활성에는 2개의 glutamic acid 또는 aspartic acid 잔기와 1개의 tryptophan 잔기가 관여하는 것으로 나타났다.

The purified xylanase from Bacillus alcalophilus AX2000 was modified with various chemical modifiers to determine amino acid residues in the active site of the enzyme. Treatment of the enzyme with group-specific reagents such as carbodiimide or N-bromosuccinimide resulted in complete loss of enzyme activity. These results suggested that these reagents reacted with glutamic acid or aspartic acid and tryptophan residues located at or near the active site. In each case, inactivation was performed by pseudo first-order kinetics. Inhibition of enzyme activity by carbodiimide and N-bromosuccinimide showed non-competitive and competitive inhibition type, respectively. Addition of xylan to the enzyme solution containing N-bromosuccinimide prevented the inactivation, indicating the presence of tryptophan at the substrate binding site. Analysis of kinetics for inactivation showed that the loss of enzyme activity was due to modification of two glutamic acid or aspartic acid residues and single tryptophan residue.

키워드

참고문헌

  1. Bandivadekar, K. R. and V. V. Deshpande. 1996. Structurefunction relationship of xylanase: tluorimetric analysis of the tryptophan environment. Biochem. J. 315: 583-587
  2. Beg, Q. K., B. Bhushan, M. Kapoor, and G. S. Hoondal. 2000. Enhanced production of a thermostable xylanase from Streptomyces sp. QG-11-3 and its application in biobleaching of eucalyptus kraft pulp. Enzyme Microb. Technol. 27: 459-466
  3. Bieley, P. 1985. Microbial xylanolytic systems. Trends Biotechnol. 3: 286-290 https://doi.org/10.1016/0167-7799(85)90004-6
  4. Blanke, S. R. and L. P. Hager. 1990. Chemical modification of chloroperoxidase with diethylpyrocarbonate. Evidence for the presence of an essential histidine residue. J. Biol. Chem. 265: 12454-12461
  5. Bradford, M. M. 1976. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal. Biochem. 72: 248-254 https://doi.org/10.1016/0003-2697(76)90527-3
  6. Church, F. C., R. L. Lundblad, and C. M. Noyes. 1985. Modification of histidines on human prothrombin. Effect in the interaction of fibrinogen with thrombin from diethylpyrocarbonate-modified prothrombin. J. Biol. Chem. 260: 4936-4940
  7. Das, N. N., S. C. Das, A. K. Sarkar, and A. K. Mukheljee. 1984. Lignin-xylan ester linkage in mesta fiber (Hibiscus cannabinus). Carbohydr. Res. 129: 197-207 https://doi.org/10.1016/0008-6215(84)85312-4
  8. Davoodi, J., W. W. Wakarchuk, R. L. Campbell, P. R. Carey, and W. K. Surewicz. 1995. Abnormally high pKa of an active site glutamic acid residue in Bacillus circulans xylanase. The role of electrostatic interactions. Eur. J. Biochem. 232: 839-843
  9. Khasin, A., I. Alchanati, and Y. Shoham. 1993. Purification and characterization of a thermostable xylanase from Bacillus stearothermophilus T-6. Appl. Environ. Microbiol. 59: 1725-1730
  10. Kulkarni, N., A. Shendye, and M. Rao. 1999. Molecular and biotechnological aspects of xylanases. FEMS Microbiol. Rev. 23: 411-456 https://doi.org/10.1111/j.1574-6976.1999.tb00407.x
  11. Laemmli, U. K. 1970. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature 227: 680-685 https://doi.org/10.1038/227680a0
  12. McCarthy, A A., D. D. Morris, P. L. Bergquist, and E. N. Baker. 2000. Structure of XynB, a highly thermostable beta1,4-xylanase from Dictyoglomus thermophilum Rt46B.1, at 1.8 A resolution. Acta Crystallogr. D. Biol. Crystallogr. 11: 1367-1375
  13. McCracken, K. J., M. R. Bedford, and R. A. Stewart. 2001. Effects of variety, the 1B/1R translocation and xylanase supplementation on nutritive value of wheat for broilers. Br. Poult. Sci. 42: 638-642 https://doi.org/10.1080/00071660120088452
  14. Nakamura, S., K. Wakabayashi, R. Nakai, R. Aono, and K. Horikoshi. 1993. Purification and some properties of an alkaline xylanase from alkaliphilic Bacillus sp. strain 41M-1. Appl. Environ. Microbiol. 59: 2311-2316
  15. Nath, D. and M. Rao. 1998. Structural and functional role of tryptophan in xylanase from an extremophilic Bacillus: assessment of the active site. Biochem. Biophys. Res. Commun. 249: 207-212 https://doi.org/10.1006/bbrc.1998.9107
  16. Park, Y. S. 2005. Molecular cloning and nucleotide sequence of xylanase gene (xynT) from Bacillus alcalophilus AX2000, J. Life Sci. 15: 734-738 https://doi.org/10.5352/JLS.2005.15.5.734
  17. Park, Y. S and T. Y. Kim. 2003. Isolation of Bacillus alcalophilus AX2000 producing alkaline xylanase and its enzyme production, Kor. J. Microbiol. Biotechnol. 31: 157-164
  18. Scalbert, A., B. Monities, J. Y. Lallemand, E. Guittet, and C. Rolando. 1985. Ether linkage between phenolic acids and lignin fractions from wheat straw. Phytochemistry 24: 1359-1362 https://doi.org/10.1016/S0031-9422(00)81133-4
  19. Somogyi, M. 1952. Notes on sugar determination J. Biol. Chem. 195: 19-23
  20. Takeuchi, M., A. Asno, Y.Kameda, and K. Matsui. 1986. Chemical modification by diethylpyrocarbonate of an essential histidine residue in 3-ketovalidoxylamine A C-N lyase. J. Biochem. 99: 1571-1577
  21. Velikodvorskaya, T. V., I. Y. Volkov, V. T. Vasilevko, V. V. Zverlov, and E. S. Piruzian. 1997. Purification and some properties of Thermotoga neapolitana thermostable xylanase B expressed in E. coli cells. Biochemistry 62: 66-70
  22. Wang, K. K. Y, L. U. L. Tan, and J. N. Saddler. 1988. Multiplicity of beta-1,4-xylanase in microorganisms: Function and applications. Microbiol. Rev. 52: 305-317
  23. Wakarchuk, W. W., R. L. Campbell, W. L. Sung, J. Davoodi, and M. Yaguchi. 1994. Mutational and crystallographic analyses of the active site residues of Bacillus circulans xylanase. Protein Sci. 3: 467-475
  24. Wong, K. K. Y and J. N. Saddler. 1992. Applications of hemicellulases in the food, feed, and pulp and paper industries, In: Hemicellulose and Hemicellulases (Coughlen, P. P. and G. P. Hazlewood, eds), pp. 127-143, Portland Press, London
  25. Xie, H.,H. J. Gilbert, S. J. Charnock, G. J. Davies, M. P. Williamson, P. J. simpson, S. Raghothama, C. M. Fontes, F. M. Dias, L. M. Ferreira, and D. N. Bolam. 2001. Clostridium thermocellum Xyn10B carbohydrate-binding module 22-2: the role of conserved amino acids in ligand binding. Biochemistry 40: 9167-9176
  26. Zhu, H., F W. Paradis, P. J. Krell, J. P. Phillips, and C. W. Forsberg. 1994. Enzymatic specificities and modes of action of the two catalytic domains of the XynC xylanase from Fibrobacter succinogenes S85. J. Bacteriol. 176: 3885-3894