Talk by Lin Zhang
Title: "Mechanistic insights into the catalysis and maturation of nitrous oxide reductase"
Occasion: SFB - Seminar
Start: 07.12.2023 - 16:15
Location: CellNanOs, 38/201
About the speaker: Dr. Lin Zhang conducts research about membrane proteins and metalloprotein at the University of Freiburg.
Abstract of the talk: The biological conversion of the environmentally critical greenhouse gas nitrous oxide (N2O) to dinitrogen (N2) is catalyzed solely by the metalloenzyme nitrous oxide reductase (N2OR). It harbors two copper centers, the binuclear CuA and the tetranuclear CuZ, in each rmonomer. Its structural gene nosZ in most cases forms part of a gene cluster of the composition nosRZDFYL. NosR is a transmembrane iron-sulfur flavoprotein that is involved in electron transfer to active N2OR, while the ABC transporter NosDFY is considered as a candidate for sulfur donation during CuZ assembly, although a periplasmic sulfide source cannot be excluded. The lipoprotein NosL is involved in copper trafficking to apo-N2OR . The maturation of N2OR requires accurate and timely interactions among NosZ, NosDFY and NosL to allow the sequential insertion of six copper ions and two sulfides for building one composite active site, but the details of the exact molecular interplay remain to be elucidated . We have employed a recombinant N2OR of Pseudomonas stutzeri as model system to study the key determinants and steps of its maturation process [3,4], and to investigate the molecular mechanisms of copper sites assembly and activation [5,6] by using a combined approach of microbiology, biochemistry, X-ray crystallography and cryo-EM single particle analysis.