Photolysis of Hi-CO Nitrogenase - Observation of a Plethora of Distinct CO Species using Infrared Spectroscopy.

ABSTRACT: Fourier transform infrared spectroscopy (FT-IR) was used to study the photochemistry of CO-inhibited Azotobacter vinelandii nitrogenase using visible light at cryogenic temperatures. The FT-IR difference spectrum of photolyzed hi-CO at 4 K comprises negative bands at 1973 cm^-1 and 1679 cm^-1 together with positive bands at 1711 cm^-1, 2135 and 2123 cm^-1. The negative bands are assigned to a hi-CO state that comprises 2 metal-bound CO ligands, one terminally bound, and one bridged and/or protonated species. The positive band at 1711 cm^-1 is assigned to a lo-CO product with a single bridged and/or protonated metal-CO group. We term these species 'Hi-1' and 'Lo-1' respectively. The high-energy bands are assigned to a liberated CO tra

SUBMITTER: Yan L 

PROVIDER: S-EPMC5019582 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature