1H2S:
reference: Molecular basis of transmembrane signalling by sensory rhodopsin II-transducer complex., Gordeliy VI, Labahn J, Moukhametzianov R, Efremov R, Granzin J, Schlesinger R, Buldt G, Savopol T, Scheidig AJ, Klare JP, Engelhard M, Nature 2002 Oct 3;419(6906):484-7. PMID: 12368857

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