Crystallization and preliminary crystallographic analysis of the proline dehydrogenase domain of the multifunctional PutA flavoprotein from Escherichia coil

S. Nadaraia, Y. H. Lee, D. F. Becker, J. J. Tanner

Research output: Contribution to journalArticlepeer-review

12 Scopus citations

Abstract

The PutA flavoprotein from Escherichia coli is a multifunctional protein that plays pivotal roles in proline catabolism by functioning as both a membrane-associated bifunctional enzyme and a transcriptional repressor. Peripherally membrane-bound PutA catalyzes the two-step oxidation of proline to glutamate, while cytoplasmic PutA represses the transcription of its own gene and the gene for a proline-transporter protein. X-ray crystallographic studies on PutA have been initiated to determine how the PutA structural scaffold enables it to be both an enzyme and a repressor, and to understand the mechanism by which PutA switches between its enzymatic and DNA-binding functions. To facilitate crystallization, a recombinant protein (PutA669) corresponding to the N-terminal 669 amino-acid residues of the 1320 residues of PutA was engineered. Activity assays demonstrated that PutA669 catalyzes the first step of chemistry performed by PutA, the conversion of proline to δ1-pyrroline5-carboxylate. Crystals of PutA669 have been obtained from PEG 3000 buffered at pH 6-7. The crystals occupy an I-centered orthorhombic lattice with unit-cell parameters a = 72.5, b = 140.2, c = 146.8 Å; a 2.15 Å data set was collected using a rotating-anode source. Assuming one molecule per asymmetric unit, the Matthews coefficient VM is 2.5 Å3 Da-1, with a solvent content of 50%. The structure of PutA669 will be solved by multiple isomorphous replacement.

Original languageEnglish (US)
Pages (from-to)1925-1927
Number of pages3
JournalActa Crystallographica Section D: Biological Crystallography
Volume57
Issue number12
DOIs
StatePublished - 2001

ASJC Scopus subject areas

  • Structural Biology

Fingerprint Dive into the research topics of 'Crystallization and preliminary crystallographic analysis of the proline dehydrogenase domain of the multifunctional PutA flavoprotein from Escherichia coil'. Together they form a unique fingerprint.

Cite this