Direct linking of metabolism and gene expression in the proline utilization A protein from Escherichia coli.
The control of gene expression by enzymes provides a direct pathway for cells to respond to fluctuations in metabolites and nutrients. One example is the proline utilization A (PutA) protein from Escherichia coli. PutA is a membrane-associated enzyme that catalyzes the oxidation of L: -proline to glutamate using a flavin containing proline dehydrogenase domain and a NAD(+) dependent Delta(1)-pyrroline-5-carboxylate dehydrogenase domain. In some Gram-negative bacteria such as E. coli, PutA is also endowed with a ribbon-helix-helix DNA-binding domain and acts as a transcriptional repressor of the proline utilization genes. PutA switches between transcriptional repressor and enzymatic functions in response to proline availability. Molecular insights into the redox-based mechanism of PutA functional switching from recent studies are reviewed. In addition, new results from cell-based transcription assays are presented which correlate PutA membrane localization with put gene expression levels. General membrane localization of PutA, however, is not sufficient to activate the put genes.
Zhou
Yuzhen
Y
Department of Biochemistry, University of Nebraska-Lincoln, N258 Beadle Center, 19th and Vine Street, Lincoln, NE 68588, USA.
Zhu
Weidong
W
Bellur
Padmanetra S
PS
Rewinkel
Dustin
D
Becker
Donald F
DF
D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology*; D002462:Cell Membrane / Q000378:metabolism; D004247:DNA / Q000737:chemistry; D004926:Escherichia coli / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D018698:Glutamic Acid / Q000737:chemistry; D007700:Kinetics; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology*; D008954:Models, Biological; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D011392:Proline / Q000737:chemistry; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D020349:Surface Plasmon Resonance; D014158:Transcription, Genetic
D001426:Bacterial Proteins; D008565:Membrane Proteins; C080683:PutA protein, Bacteria; D018698:Glutamic Acid; D004247:DNA; D011392:Proline; D010100:Oxygen