Unique structural features and sequence motifs of proline utilization A (PutA)

Ranjan K Singh, John J Tanner

Research output: Contribution to journalArticle

17 Citations (Scopus)


Proline utilization A proteins (PutAs) are bifunctional enzymes that catalyze the oxidation of proline to glutamate using spatially separated proline dehydrogenase and pyrroline-5-carboxylate dehydrogenase active sites. Here we use the crystal structure of the minimalist PutA from Bradyrhizobium japonicum (BjPutA) along with sequence analysis to identify unique structural features of PutAs. This analysis shows that PutAs have secondary structural elements and domains not found in the related monofunctional enzymes. Some of these extra features are predicted to be important for substrate channeling in BjPutA. Multiple sequence alignment analysis shows that some PutAs have a 17-residue conserved motif in the C-terminal 20-30 residues of the polypeptide chain. The BjPutA structure shows that this motif helps seal the internal substrate-channeling cavity from the bulk medium. Finally, it is shown that some PutAs have a 100-200 residue domain of unknown function in the C-terminus that is not found in minimalist PutAs. Remote homology detection suggests that this domain is homologous to the oligomerization beta-hairpin and Rossmann fold domain of BjPutA.

Original languageEnglish
Pages (from-to)556-568
Number of pages13
JournalFrontiers in Bioscience (Landmark edition)
Publication statusPublished - 2012


  • 1-Pyrroline-5-Carboxylate Dehydrogenase
  • Amino Acid Motifs
  • Amino Acid Sequence
  • Bacterial Proteins
  • Bradyrhizobium
  • Catalytic Domain
  • Conserved Sequence
  • Membrane Proteins
  • Models, Molecular
  • Molecular Sequence Data
  • Phylogeny
  • Proline Oxidase
  • Protein Structure, Tertiary
  • Sequence Homology, Amino Acid

Fingerprint Dive into the research topics of 'Unique structural features and sequence motifs of proline utilization A (PutA)'. Together they form a unique fingerprint.

Cite this