Workshop summary: How is the MoFe protein organized to fix nitrogen?

Abstract

The complexities of the structural organization and biochemical-biophysical features of the nitrogenase MoFe protein and its complement of metalloclusters has intrigued and confounded researchers for the past several decades. Although there has been recent dramatic progress, certain fundamental questions concerning nitrogenase catalysis and the role of the MoFe protein in that process remain unanswered. For example, how does the MoFe protein manage its interactions with such a wide variety of molecules, including the Fe protein and certain non-physiological electron donors, the large range of small-molecule electron acceptors (e.g., N₂, H⁺, C₂H₂, HCN, N₂O) and inhibitors (e.g., CO, H₂, CN”, NO)? And how are all these inputs correlated intra-molecularly such that ambient temperature and pressure nitrogen fixation ensues! Also, what is the molecular structure of the metal loc lusters, how are they distributed within the MoFe protein and what role in catalysis does each cluster type have? In this Workshop, progress made in research aimed at addressing these and related questions was discussed. These discussions are summarized here and placed within the context of relevant data and ideas reported prior to and during the Congress.