passages.id: split_4_test_804_passage
passages.type: progene_text
passages.text: A type II change ( red shift ) of the Soret band ( 405 nm --> 413 - 419 nm ) was observed when wild - type HO-2 was treated with sodium nitroprusside ( SNP ) , S-nitroglutathione ( GSNO ) , S-nitroso-N-acetylpenicillamine ( SNAP ) or 3-morpholinosydnonimine ( SIN-1 ) ; the NO scavenger , hydroxocobalamin ( HCB ) prevented the shift .