PrcR, a PucR-type transcriptional activator, is essential for proline utilization and mediates proline-responsive expression of the proline utilization operon putBCP in Bacillus subtilis

Huang, Shih-Chien; Lin, Ta-Hui; Shaw, Gordon L.

doi:10.1099/mic.0.054197-0

Cited by 11 publications

(21 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recently, the understanding of the genetic control of the use of L-proline as a nutrient by B. subtilis was advanced by the identification of a proline-responsive activator protein (PutR) that controls the expression of the L-proline utilization putBCP (formerly ycgMNO [9]) gene cluster (7,31). PutR activates putBCP transcription in response to proline availability but can be displaced by an active form of the negatively acting CodY regulatory protein (4,44,54) from the putBCP promoter region (7), thereby establishing repression of the gene cluster.…”

mentioning

confidence: 99%

Proline Utilization by Bacillus subtilis: Uptake and Catabolism

et al. 2012

View full text Add to dashboard Cite

L-Proline can be used by Bacillus subtilis as a sole source of carbon or nitrogen. We traced L-proline utilization genetically to the putBCP (ycgMNO) locus. The putBCP gene cluster encodes a high-affinity proline transporter (PutP) and two enzymes, the proline dehydrogenase PutB and the ⌬ 1 -pyrroline-5-carboxylate dehydrogenase PutC, which jointly catabolize L-proline to L-glutamate. Northern blotting, primer extension, and putB-treA reporter gene fusion analysis showed that the putBCP locus is transcribed as an L-proline-inducible operon. Its expression was mediated by a SigA-type promoter and was dependent on the proline-responsive PutR activator protein. Induction of putBCP expression was triggered by the presence of submillimolar concentrations of L-proline in the growth medium. However, the very large quantities of L-proline (up to several hundred millimolar) synthesized by B. subtilis as a stress protectant against high osmolarity did not induce putBCP transcription. Induction of putBCP transcription by external L-proline was not dependent on L-proline uptake via the substrate-inducible PutP or the osmotically inducible OpuE transporter. It was also not dependent on the chemoreceptor protein McpC required for chemotaxis toward L-proline. Our findings imply that B. subtilis can distinguish externally supplied L-proline from internal L-proline pools generated through de novo synthesis. The molecular basis of this regulatory phenomenon is not understood. However, it provides the B. subtilis cell with a means to avoid a futile cycle of de novo L-proline synthesis and consumption by not triggering the expression of the putBCP L-proline catabolic genes in response to the osmoadaptive production of the compatible solute L-proline.

show abstract

mentioning

confidence: 99%

Proline Utilization by Bacillus subtilis: Uptake and Catabolism

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Data derived from transcriptional profiling experiments suggest that it is also under the positive control of the central carbon metabolism regulatory protein CcpA (79). Transcription of the putBCP operon is activated by the prolineresponsive PutR regulator (10,28,29), whereas that of the gabP gene is enhanced through the stimulating activity of TnrA (42,69), the central regulator of nitrogen metabolism in B. subtilis (12,26,27). Notably, transcription of gabP is not under the control of GabR, a regulatory protein that controls the expression of the gabTD GABA catabolic operon (71,80).…”

Section: Discussionmentioning

confidence: 99%

“…S2 and S3 in the supplemental material), indicating that this fourth proline import route is of limited physiological relevance as far as the use of proline as a nutrient (10) and as an osmoprotectant (15,16) is concerned. Nevertheless, enough proline can enter the B. subtilis cell via this route to induce enhanced expression of a prolineresponsive (10,28,29) put-treA reporter fusion ( Table 4).…”

Section: Discussionmentioning

confidence: 99%

“…Their primary physiological roles can be discerned from the distinct transcriptional profile of their structural genes (10,16,23,28,29) and the different abilities of the PutP and OpuE proteins to withstand the inhibiting effects of high salinity on their transport activity (10). These features associate PutP with the proline catabolic system of B. subtilis (10,28,29) and OpuE with the cell's osmostress response systems (16,22,72,73). Nevertheless, it is worth noting that our data now show not only that the OpuE transporter imports proline when it is used as an osmoprotectant (15,16) but also that it can do so when B. subtilis uses it as a nutrient (see Fig.…”

Section: Discussionmentioning

confidence: 99%

“…Utilization of proline as a nutrient requires its capture from environmental sources, such as root exudates and organic deposits in the rhizosphere (2,25), and relies on the PutB-and PutC-mediated catabolism to glutamate (10), a central intermediate in the interconnected carbon and nitrogen utilization systems of B. subtilis (26,27). The PutP transporter mediates the uptake of proline for its use as a nutrient, and the induction of the expression of the catabolic putBCP operon by an external supply of the substrate proline reflects this role (10,28,29).…”

mentioning

confidence: 99%

See 2 more Smart Citations

The γ-Aminobutyrate Permease GabP Serves as the Third Proline Transporter of Bacillus subtilis

et al. 2014

View full text Add to dashboard Cite

bPutP and OpuE serve as proline transporters when this imino acid is used by Bacillus subtilis as a nutrient or as an osmostress protectant, respectively. The simultaneous inactivation of the PutP and OpuE systems still allows the utilization of proline as a nutrient. This growth phenotype pointed to the presence of a third proline transport system in B. subtilis. We took advantage of the sensitivity of a putP opuE double mutant to the toxic proline analog 3,4-dehydro-DL-proline (DHP) to identify this additional proline uptake system. DHP-resistant mutants were selected and found to be defective in the use of proline as a nutrient. Whole-genome resequencing of one of these strains provided the lead that the inactivation of the ␥-aminobutyrate (GABA) transporter GabP was responsible for these phenotypes. DNA sequencing of the gabP gene in 14 additionally analyzed DHPresistant strains confirmed this finding. Consistently, each of the DHP-resistant mutants was defective not only in the use of proline as a nutrient but also in the use of GABA as a nitrogen source. The same phenotype resulted from the targeted deletion of the gabP gene in a putP opuE mutant strain. Hence, the GabP carrier not only serves as an uptake system for GABA but also functions as the third proline transporter of B. subtilis. Uptake studies with radiolabeled GABA and proline confirmed this conclusion and provided information on the kinetic parameters of the GabP carrier for both of these substrates.

show abstract

l-Proline catabolism by the high G + C Gram-positive bacterium Paenarthrobacter aurescens strain TC1

Deutch

2018

Antonie van Leeuwenhoek

View full text Add to dashboard Cite

Paenarthrobacter aurescens (formerly called Arthrobacter aurescens) strain TC1 is a high G + C Gram-positive aerobic bacterium that can degrade the herbicide atrazine. Analysis of its genome indicated strain TC1 has the potential to form a bifunctional PutA protein containing L-proline dehydrogenase and L-glutamate-γ-semialdehyde dehydrogenase (L-Δ-pyrroline-5-carboxylate dehydrogenase) activities. P. aurescens strain TC1 grew well in minimal media with L-Proline as a supplemental nutrient, the nitrogen source, or the sole carbon and nitrogen source. Multicellular myceloids induced by NaCl or citrate also grew on L-proline. The specific activity of L-proline dehydrogenase in whole cells was higher whenever L-proline was added to the medium. Both L-proline dehydrogenase and L-glutamate-γ-semialdehyde dehydrogenase (L-Δ-pyrroline-5-carboxylate dehydrogenase) activities were found primarily in a membrane fraction from exponential-phase cells. The two activities co-eluted from a Bio-Gel P-60 column after precipitation of proteins with ammonium sulfate and solubilization with 0.1% Tween 20. The PutA protein in the active fraction also oxidized 3,4-dehydro-DL-proline, but there was no activity with other L-proline analogues. When P. aurescens strain TC1 was grown in minimal media containing increasing concentrations of NaCl, there was a progressive decrease in the specific activity of L-proline dehydrogenase and a concomitant increase in the intracellular concentration of L-proline. These results indicate that P. aurescens strain TC1 can use L-proline as a nutrient in a regulated fashion. Because this bacterium also showed the ability to degrade most of the other common amino acids, it can serve as a useful model for the control of amino acid catabolism in the high G + C Actinobacteria.

show abstract

PrcR, a PucR-type transcriptional activator, is essential for proline utilization and mediates proline-responsive expression of the proline utilization operon putBCP in Bacillus subtilis

Cited by 11 publications

References 28 publications

Proline Utilization by Bacillus subtilis: Uptake and Catabolism

Proline Utilization by Bacillus subtilis: Uptake and Catabolism

The γ-Aminobutyrate Permease GabP Serves as the Third Proline Transporter of Bacillus subtilis

l-Proline catabolism by the high G + C Gram-positive bacterium Paenarthrobacter aurescens strain TC1

Contact Info

Product

Resources

About