Response to excess copper in the hyperthermophile Sulfolobus solfataricus strain 98/2.
Copper is an essential micronutrient, but toxic in excess. Sulfolobus solfataricus cells have the ability to adapt to fluctuations of copper levels in their external environment. To better understand the molecular mechanism behind the organismal response to copper, the expression of the cluster of genes copRTA, which encodes the copper-responsive transcriptional regulator CopR, the copper-binding protein CopT, and CopA, has been investigated and the whole operon has been shown to be cotranscribed at low levels from the copR promoter under all conditions, whereas increased transcription from the copTA promoter occurs in the presence of excess copper. Furthermore, the expression of the copper-transporting ATPase CopA over a 27-h interval has been monitored by quantitative real-time RT-PCR and compared to the pattern of cellular copper accumulation, as determined in a parallel analysis by Inductively Coupled Plasma Optical Emission spectrometry (ICP-OES). The results provide the basis for a model of the molecular mechanisms of copper homeostasis in Sulfolobus, which relies on copper efflux and sequestration.
Villafane
Aramis A
AA
Department of Biochemistry and Microbiology, and Biotechnology Center for Agriculture and the Environment, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901-8525, USA.
Voskoboynik
Yekaterina
Y
Cuebas
Mariola
M
Ruhl
Ilona
I
Bini
Elisabetta
E
D019843:Archaeal Proteins / Q000096:biosynthesis* / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics; D003300:Copper / Q000378:metabolism* / Q000633:toxicity; D015870:Gene Expression; D019848:Gene Expression Regulation, Archaeal; D048229:Sulfolobus solfataricus / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D015534:Trans-Activators / Q000235:genetics; D014158:Transcription, Genetic / Q000187:drug effects
D019843:Archaeal Proteins; D002352:Carrier Proteins; D015534:Trans-Activators; C023548:copper-binding protein; D003300:Copper