Molecular Insights into a Novel Cu(I)-Sensitive ArsR/SmtB Family Repressor in Extremophile Acidithiobacillus caldus.

ABSTRACT: Acidithiobacillus caldus is a common bioleaching bacterium that is inevitably exposed to extreme copper stress in leachates. The ArsR/SmtB family of metalloregulatory repressors regulates homeostasis and resistance in bacteria by specifically responding to metals. Here, we characterized A. caldus Cu(I)-sensitive repressor (AcsR) and gained molecular insights into this new member of the ArsR/SmtB family. Transcriptional analysis indicated that the promoter (PIII) of acsR was highly active in Escherichia coli but inhibited upon AcsR binding to the PIII-acsR region. Size exclusion chromatography and circular dichroism spectra revealed that Cu^I-AcsR shared an identical assembly state with apo-AcsR, as a dimer with fewer α helices, more extended strands, and more

SUBMITTER: Qiu Y 

PROVIDER: S-EPMC9888290 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature