A novel unhairing enzyme produced by heterologous expression of keratinase gene (kerT) in Bacillus subtilis

  • Shan CaoEmail author
  • Dengke Li
  • Xiaoxiao Ma
  • Qinglong Xin
  • Jinzhi Song
  • Fuping Lu
  • Yu LiEmail author
Original Paper


To promote enzymatic unhairing for leather production, a new unhairing enzyme is developed. The Keratinase (kerT) gene, which is amplified from B. amyloliquefaciens TCCC11319 by PCR, is expressed in B. subtilis WB600. The recombinant KerT reduces the collagenolytic protease content as well as improving the keratinase content effectively. Therefore, the improved keratinase leads to the obviously unhairing effect, whereas the low collagenolytic protease ensures the integrity of collagen fibers in hide. It represents, the leather grain surface isn’t destroyed thereby the value of finished leather can be maintained. In addition, by analyzing the properties of KerT, tits activity isn’t inhibited with Na+, K+ and Ca2+ which are commonly used in leather production. The freeze-dried fermentation broth can be used directly as unhairing enzyme without addition of traditional sulfide chemicals. By evaluating the properties of unhaired hide, the results show that the collagen degradation ability of this new unhairing enzyme is slightly and it does not cause any adverse effects on the leather quality. Besides, this unhairing enzyme doesn’t further degrade collagen in the time range of 8 h to 24 h, thus it is safely and easy-control in actual production. In conclusion, the enzymatic unhairing method with recombinant KerT has the potential to be more sustainable and efficient alternative than current sulphur-lime method, and it does not require the further purification thereby saving the cost.


Unhairing enzyme Heterologous expression KerT gene 



This work was financially supported by The National Key Research and Development Program of China (Grant No. 2017YFB0308401), National Natural Science Foundation of China (Grant No. 21808170), and Shandong Provincial Natural Science Foundation (Grant No. ZR201807260006).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.

Supplementary material

11274_2019_2701_MOESM1_ESM.doc (1.5 mb)
Supplementary file1 (DOC 1488 kb)


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Copyright information

© Springer Nature B.V. 2019

Authors and Affiliations

  1. 1.Key Laboratory of Industrial Fermentation Microbiology, College of BiotechnologyTianjin University of Science and TechnologyTianjinChina
  2. 2.School of Light Industry and EngineeringQilu University of TechnologyShandongChina

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