Photobiochemical production of carbon monoxide by Thermus thermophilus ba3 -cytochrome c oxidase.

We report the photobiochemical production of carbon monoxide by a terminal ba3 -cytochrome c oxidase from T. thermophilus HB8. FTIR and time-resolved step-scan FTIR spectroscopies were combined to probe this process and also monitor the concomitant binding of the produced gas to other intact ba3 molecules forming the ba3 -CO complex. The activation of this mechanism by ba3 -oxidase under visible excitation raises the question as to whether such a mechanism is physiologically relevant to the extreme environment in which it operates.