Bacterial Tannases: Classification and Biochemical Properties

Appl Microbiol Biotechnol. 2019 Jan;103(2):603-623. doi: 10.1007/s00253-018-9519-y. Epub 2018 Nov 20.


Tannin acyl hydrolases, also known as tannases, are a group of enzymes critical for the transformation of tannins. The study of these enzymes, which initially evolved in different organisms to detoxify and/or use these plant metabolites, has nowadays become relevant in microbial enzymology research due to their relevant role in food tannin transformation. Microorganisms, particularly bacteria, are major sources of tannase. Cloning and heterologous expression of bacterial tannase genes and structural studies have been performed in the last few years. However, a systematic compilation of the information related to all recombinant tannases, their classification, and characteristics is missing. In this review, we explore the diversity of heterologously produced bacterial tannases, describing their substrate specificity and biochemical characterization. Moreover, a new classification based on sequence similarity analysis is proposed. Finally, putative tannases have been identified in silico for each group of tannases taking advantage of the use of the "tannase" distinctive features previously proposed.

Keywords: Esterase; Feruloyl esterase; Gallic acid; Hydrolyzable tannins; Tannase.

Publication types

  • Review

MeSH terms

  • Bacterial Proteins / chemistry
  • Bacterial Proteins / classification
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Carboxylic Ester Hydrolases / chemistry
  • Carboxylic Ester Hydrolases / classification
  • Carboxylic Ester Hydrolases / genetics
  • Carboxylic Ester Hydrolases / metabolism*
  • Genetic Variation
  • Hydrolysis
  • Phytochemicals / metabolism
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / classification
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism*
  • Tannins / metabolism*


  • Bacterial Proteins
  • Phytochemicals
  • Recombinant Proteins
  • Tannins
  • Carboxylic Ester Hydrolases
  • tannase