African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5233

Full Length Research Paper

Identification of fibrinogen-induced nattokinase WRL101 from Bacillus subtilis WRL101 isolated from Doenjang

Chang-Su Park1, Dong Ho Kim2, Woo-Yiel Lee3, Dae-Ook Kang4, Jae Jun Song5*andNack-Shick Choi4,6*
1Department of Food Science and Technology, Catholic University of Daegu, Korea. 2Advanced Radiation Technology Research Institute, KAERI, Jeonbuk Branch Institute,Jeongeup, Korea. 3Department of Pharmaceutical Engineering, Konyang University, Nonsan 320-711, Korea. 4Department of Biochemistry and Health Science, Changwon National University, Changwon, Korea. 5Institute Bioindustry Research Center, KRIBB, Jeonbuk, Korea. 6Woori Life Science Co., Ltd., Cheonan-si, Chungnam, Korea.
Email: [email protected],[email protected]

  •  Accepted: 08 January 2013
  •  Published: 07 May 2013


To increase the fibrinolytic enzyme (nattokinase WRL101) in Bacillus subtilis WRL101, bovine fibrin or fibrinogen (1.0%, w/v) were added in the tryptic soy broth as a substrate. The fibrinolytic activity cultured in the fibrinogen-contained medium was increased. On the other hand, fibrin decreased the activity. Using the medium condition, nattokinase WRL101 (fibrinogen-induced nattokinase WRL101, FIN-WRL101) was isolated by commercial chromatographic techniques and its biochemical characteristics were investigated. The molecular weight of FIN-WRL101 was estimated to be 29 kDa. FIN-WRL101 was optimally active at pH 11.0 and 47°C. It had high degrading activity for the Aα-chain and Bb-chain of human fibrinogen, but did not affect the g-chain, indicating that it is an a-fibrinogenase. FIN-WRL101 was completely inhibited by phenylmethylsulfonyl fluoride, indicating that it belongs to the serine protease. FIN-WRL101 exhibited high specificity for Meo-Suc-Arg-Pro-Tyr-pNA (S-2586), a synthetic chromogenic substrate for chymotrypsin. Its nucleotide and amino acid sequences were determined.


Key words: Bacillus subtilisDoenjang, fibrinolytic enzyme, nattokinase.