Biochemical and molecular characterization of taurine:pyruvate aminotransferase from the anaerobe Bilophila wadsworthia

Eur J Biochem. 2000 Dec;267(23):6841-8. doi: 10.1046/j.1432-1033.2000.01782.x.


Bilophila wadsworthia RZATAU is a Gram-negative bacterium which converts the sulfonate taurine (2-aminoethanesulfonate) to ammonia, acetate and sulfide in an anaerobic respiration. Taurine:pyruvate aminotransferase (Tpa) catalyses the initial metabolic reaction yielding alanine and sulfoacetaldehyde. We purified Tpa 72-fold to apparent homogeneity with an overall yield of 89%. The purified enzyme did not require addition of pyridoxal 5'-phosphate, but highly active enzyme was only obtained by addition of pyridoxal 5'-phosphate to all buffers during purification. SDS/PAGE revealed a single protein band with a molecular mass of 51 kDa. The apparent molecular mass of the native enzyme was 197 kDa as determined by gel filtration, which indicates a homotetrameric structure. The kinetic constants for taurine were: Km = 7.1 mM, Vmax = 1.20 nmol.s-1, and for pyruvate: Km = 0.82 mM, Vmax = 0.17 nmol.s-1. The purified enzyme was able to transaminate hypotaurine (2-aminosulfinate), taurine, beta-alanine and with low activity cysteine and 3-aminopropanesulfonate. In addition to pyruvate, 2-ketobutyrate and oxaloacetate were utilized as amino group acceptors. We have sequenced the encoding gene (tpa). It encoded a 50-kDa peptide, which revealed 33% identity to diaminopelargonate aminotransferase from Bacillus subtilis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Butyrates / metabolism
  • Chromatography, Gel
  • Chromatography, High Pressure Liquid
  • Cysteine / metabolism
  • Deltaproteobacteria / enzymology*
  • Electrophoresis, Polyacrylamide Gel
  • Kinetics
  • Models, Chemical
  • Molecular Sequence Data
  • Molecular Weight
  • Open Reading Frames
  • Oxaloacetic Acid / metabolism
  • Pyridoxal Phosphate / pharmacology
  • Taurine / analogs & derivatives*
  • Taurine / metabolism
  • Time Factors
  • Transaminases / chemistry*
  • Transaminases / genetics*
  • Ultraviolet Rays
  • beta-Alanine / metabolism


  • Butyrates
  • beta-Alanine
  • Taurine
  • Oxaloacetic Acid
  • tramiprosate
  • hypotaurine
  • Pyridoxal Phosphate
  • alpha-ketobutyric acid
  • Transaminases
  • taurine pyruvate aminotransferase
  • Cysteine

Associated data

  • GENBANK/AF269146