3CWF:
reference: Extracytoplasmic PAS-like domains are common in signal transduction proteins., Chang C, Tesar C, Gu M, Babnigg G, Joachimiak A, Pokkuluri PR, Szurmant H, Schiffer M, J Bacteriol. 2010 Feb;192(4):1156-9. Epub 2009 Dec 11. PMID: 20008068

This OCA Structure page
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