Structural insights into a maleylpyruvate hydrolase from sphingobium sp. SYK-6, a bacterium degrading lignin-derived aryls

Biochem Biophys Res Commun. 2019 Jun 30;514(3):765-771. doi: 10.1016/j.bbrc.2019.05.030. Epub 2019 May 9.


Sphingobium sp. strain SYK-6, an aerobic gram-negative bacillus found in soil, is known for utilizing lignin-derived monoaryls and biaryls as carbon sources and degrading aromatic compounds. The Sphingobium sp. strain SYK-6 genome contains three genes involved in salicylate catabolism: SLG_11260, SLG_11270, and SLG_11280. Here, we report that the gene product of SLG_11280 functions as a maleylpyruvate hydrolase (SsMPH) with Km and Kcat values of 166.2 μM and 3.76 min-1, respectively. This study also reveals the crystal structures of both the apo and pyruvate-manganese ion-bound SsMPH, which revealed that like other fumarylacetoacetate hydrolases, SsMPH dimerizes and has nine unique 310-helices. Molecular docking studies of maleylpyruvate also revealed the likely binding mode of SsMPH and its substrate.

Keywords: Crystal structure; Maleylpyruvate hydrolase; Salicylate catabolism; Sphingobium sp. strain SYK-6.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Catalytic Domain
  • Hydrolases / chemistry*
  • Hydrolases / metabolism*
  • Lignin / metabolism*
  • Models, Molecular
  • Salicylic Acid / metabolism
  • Sphingomonadaceae / enzymology*
  • Substrate Specificity


  • Lignin
  • Hydrolases
  • maleylpyruvate hydrolase
  • Salicylic Acid