Crystallographic structure of the PAS domain of the bacterial oxygen sensor protein fixL. The protein is depicted as a rainbow colored cartoon (N-terminus = blue, C-terminus = red while the heme ligand is shown as sticks (carbon = white, nitrogen = blue, oxygen = red, iron = orange).
The PAS domain is a protein domain contained in many signaling proteins where it functions as a signal sensor. PAS domains are found in a large number of organisms from bacteria to humans. The PAS domain was named after the three proteins in which it was first discovered:
^PDB: 1y28; Dunham CM, Dioum EM, Tuckerman JR, Gonzalez G, Scott WG, Gilles-Gonzalez MA (July 2003). "A distal arginine in oxygen-sensing heme-PAS domains is essential to ligand binding, signal transduction, and structure". Biochemistry42 (25): 7701–8. doi:10.1021/bi0343370. PMID12820879.
^Hefti MH, Françoijs KJ, de Vries SC, Dixon R, Vervoort J (March 2004). "The PAS fold. A redefinition of the PAS domain based upon structural prediction". Eur. J. Biochem.271 (6): 1198–208. doi:10.1111/j.1432-1033.2004.04023.x. PMID15009198.