Biochemical evidence of both copper chelation and oxygenase activity at the histidine brace
Artikel i vetenskaplig tidskrift, 2020
Lytic polysaccharide monooxygenase (LPMO) and copper binding protein CopC share a similar mononuclear copper site. This site is defined by an N-terminal histidine and a second internal histidine side chain in a configuration called the histidine brace. To understand better the determinants of reactivity, the biochemical and structural properties of a well-described cellulose-specific LPMO from Thermoascus aurantiacus (TaAA9A) is compared with that of CopC from Pseudomonas fluorescens (PfCopC) and with the LPMO-like protein Bim1 from Cryptococcus neoformans. PfCopC is not reduced by ascorbate but is a very strong Cu(II) chelator due to residues that interacts with the N-terminus. This first biochemical characterization of Bim1 shows that it is not redox active, but very sensitive to H2O2, which accelerates the release of Cu ions from the protein. TaAA9A oxidizes ascorbate at a rate similar to free copper but through a mechanism that produce fewer reactive oxygen species. These three biologically relevant examples emphasize the diversity in how the proteinaceous environment control reactivity of Cu with O2.
Författare
Søren Brander
Köpenhamns universitet
Istvan Horvath
Chalmers, Biologi och bioteknik, Kemisk biologi
Johan Ipsen
Köpenhamns universitet
Ausra Peciulyte
Chalmers, Biologi och bioteknik, Industriell bioteknik
Lisbeth Olsson
Chalmers, Biologi och bioteknik, Industriell bioteknik
Cristina Hernández-Rollán
Danmarks Tekniske Universitet (DTU)
Morten H.H. Nørholm
Danmarks Tekniske Universitet (DTU)
Susanne Mossin
Danmarks Tekniske Universitet (DTU)
Leila Lo Leggio
Köpenhamns universitet
Corinna Probst
Duke University
Dennis J. Thiele
Duke University
Katja Salomon Johansen
Chalmers, Biologi och bioteknik, Industriell bioteknik
Köpenhamns universitet
Scientific Reports
2045-2322 (ISSN) 20452322 (eISSN)
Vol. 10 1 16369Ämneskategorier
Biokemi och molekylärbiologi
Biofysik
Strukturbiologi
DOI
10.1038/s41598-020-73266-y