The Sulfolobus solfataricus Lrp-like Protein LysM Regulates Lysine Biosynthesis in Response to Lysine Availability
Although the archaeal transcription apparatus resembles the eukaryal RNA polymerase II system, many bacterial-like regulators can be found in archaea. Particularly, all archaeal genomes sequenced to date contain genes encoding homologues of Lrp (leucine-responsiveregulatory protein). Whereas Lrp-lik...
Gespeichert in:
Veröffentlicht in: | The Journal of biological chemistry 2002-08, Vol.277 (33), p.29537-29549 |
---|---|
Hauptverfasser: | , , , , |
Format: | Artikel |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | Although the archaeal transcription apparatus resembles the eukaryal RNA polymerase II system, many bacterial-like regulators can be found in archaea. Particularly, all archaeal genomes sequenced to date contain genes encoding homologues of Lrp (leucine-responsiveregulatory protein). Whereas Lrp-like proteins in bacteria are involved in regulation of amino acid metabolism, their physiological role in archaea is unknown. Although several archaeal Lrp-like proteins have been characterized recently, no target genes apart from their own coding genes have been discovered yet, and no ligands for these regulators have been identified so far. In this study, we show that the Lrp-like protein LysM from Sulfolobus solfataricus is involved in the regulation of lysine and possibly also arginine biosynthesis, encoded by the lys gene cluster. Exogenous lysine is the regulatory signal for lysgene expression and specifically serves as a ligand for LysM by altering its DNA binding affinity. LysM binds directly upstream of the TFB-responsive element of the intrinsically weak lysWpromoter, and DNA binding is favored in the absence of lysine, whenlysWXJK transcription is maximal. The combined in vivo and in vitro data are most compatible with a model in which the bacterial-like LysM activates the eukarya-like transcriptional machinery. As with transcriptional activation by Escherichia coli Lrp, activation by LysM is apparently dependent on a co-activator, which remains to be identified. |
---|---|
ISSN: | 0021-9258 1083-351X |
DOI: | 10.1074/jbc.M203528200 |