Applied Microbiology and Biotechnology

, Volume 101, Issue 21, pp 7771–7779 | Cite as

Keratinolytic protease: a green biocatalyst for leather industry

  • Zhen Fang
  • Yang-Chun Yong
  • Juan ZhangEmail author
  • Guocheng Du
  • Jian Chen


Depilation/unhairing is the crucial but heavy pollution process in leather industry. Traditional inorganic sulfide treatment was the most widely used depilation technique in the past decades, which was usually detrimental to leather quality and resulted in serious environmental pollution. Using biocatalysts to substitute inorganic sulfide showed great advantages in environment protection and unhairing efficiency. Keratinolytic protease is one of the excellent biocatalysts to hydrolyze disulfide bond-rich proteins of hair and has little damage to leather. Biological treatment with keratinolytic proteases could largely reduce the quantity and toxicity of wastewater effluent from the leather industry. But low thermostability and substrate specificity or specific activity of these enzymes limited their practical application. Therefore, recent progresses on protein engineering strategies (site-directed mutagenesis, protein fusion, N/C-terminus truncation, and domain swapping) used to enhance the keratinolytic enzyme performance were presented.


Unhairing process Enzymatic catalyst Industrial biotechnology Protein engineering Lime sulfide free Keratinolytic proteases 



This work was supported by the project of Integration of Industry, Education, and Research of Jiangsu Province, China (BY2016022-39), supported by the National Natural Science Foundation of China (31470160), supported by the Major State Basic Research Development Program of China (973 Program, 2013CB733902); this work was also supported by Natural Science Foundation of Jiangsu Province (BK20160015) and a project funded by the Priority Program Development of Jiangsu Higher Education Institutions.

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.


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Copyright information

© Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  • Zhen Fang
    • 1
    • 2
  • Yang-Chun Yong
    • 1
  • Juan Zhang
    • 2
    • 3
    Email author
  • Guocheng Du
    • 2
    • 4
  • Jian Chen
    • 2
    • 5
  1. 1.Biofuels Institute, School of the EnvironmentJiangsu UniversityZhenjiangChina
  2. 2.School of BiotechnologyJiangnan UniversityWuxiChina
  3. 3.Key Laboratory of Industrial Biotechnology, Ministry of EducationJiangnan UniversityWuxiChina
  4. 4.Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of EducationJiangnan UniversityWuxiChina
  5. 5.National Engineering Laboratory for Cereal Fermentation TechnologyJiangnan UniversityWuxiChina

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