Electron paramagnetic resonance study reveals a putative iron-sulfur cluster in human rpS3 protein.
The human ribosomal protein S3 (rpS3) functions as a component of the 40S subunit and as a UV DNA repair endonuclease. This enzyme has an endonuclease activity for UV-irradiated and oxidatively damaged DNAs. DNA repair endonucleases recognize a variety of UV and oxidative base damages in DNA from E. coli to human cells. E. coli endonuclease III is especially known to have an iron-sulfur cluster as a co-factor. Here, we tried an electron paramagnetic resonance (EPR) method for the first time to observe a known iron-sulfur cluster signal from E. coli endonuclease III that was previously reported. We compared it to the human rpS3 in order to find out whether or not the human protein contains an iron-sulfur cluster. As a result, we succeeded in observing a Fe EPR signal that is apparently from an iron-sulfur cluster in the human rpS3 endonuclease. The EPR signal from the human enzyme, consisting of three major parts, is similar to that from the E. coli enzyme, but it has a distinct extra peak.
Lee
Chang Hoon
CH
Laboratory of Biochemistry, Graduate School of Biotechnology and BioInstitute, Korea University, Seoul.
Kim
Sang Hwa
SH
Choi
Jun Il
JI
Choi
Jin Young
JY
Lee
Cheol Eui
CE
Kim
Joon
J
D043224:Deoxyribonuclease (Pyrimidine Dimer); D004578:Electron Spin Resonance Spectroscopy; D004706:Endodeoxyribonucleases / Q000737:chemistry / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D029968:Escherichia coli Proteins; D006801:Humans; D007506:Iron-Sulfur Proteins / Q000737:chemistry / Q000235:genetics; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics; D012269:Ribosomal Proteins / Q000737:chemistry* / Q000235:genetics
D029968:Escherichia coli Proteins; D007506:Iron-Sulfur Proteins; D011994:Recombinant Proteins; D012269:Ribosomal Proteins; C044152:ribosomal protein S3; D004706:Endodeoxyribonucleases; D043224:Deoxyribonuclease (Pyrimidine Dimer); C106403:NTH protein, E coli