Title :

Grafting High Affinity Metal Coordination to Design Artificial Metalloproteins

Abstract :

Metalloproteins represent some of the best-known inorganic catalysts in nature, catalyzing difficult and important reactions with exceptional efficiency. 1 Design of artificial metalloproteins allows us to understand the critical features required for their structure and function. Equipped with this knowledge it is possible to engineer novel structures and functions not found in nature. In the first part of this talk I will focus on our efforts in de novo metalloprotein design to build self-assembling polypeptide systems capable of sequestering toxic heavy metals (Cd, Pb, Hg) with exceptionally high affinity and site-selective molecular recognition properties, and highlight the factors that control these properties. 2 In the second part I will describe a biosynthetic metalloprotein design approach to successfully engineer artificial biocatalysts mimicking a complex metalloenzyme involved in biological denitrification (nitric oxide reductases that reduce NO to N 2 ). 3 I will discuss how these model systems help us delineate the likely mechanisms by which this enzyme catalyzes this
environmentally important reaction.

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