Converts heme B (protoheme IX) to heme O by substitution of the vinyl group on carbon 2 of heme B porphyrin ring with a hydroxyethyl farnesyl side group (By similarity). ctaB 608 COXX_THET8 Protoheme IX farnesyltransferase Heme B farnesyltransferase TTHA0310 Heme O synthase MKTPAWSRLAGYAWGVLLWNVLVALFGAYVRATGSGAGCGAHWPTCNGEVIPRAPQVETLIEFTHRATSGLAFLSVLALFLWALRAFPKGHPARFGAGLALFFMVTESLVGASLVLFGWTADNVSRERAVVQMVHLANTYFLLAALALTAWWASGGGPLRLRGQGAVGLALFLGLLALLFLGMSGAVTALGDLLFPVGSTLEALERSLTPGEHFLVRLRVLHPLIAVSVGLYVVFAGYLVAHLRPSPLTRRLAQGLAYLYGAQLLAGLINVALKAPVWMQILHLLLAYAIWLLFVFLATSALERGAKRVELGEGGEAVHRGTGGATWRDYLALTKPRVISLLLFTALFGALIAAKGWPGLGVFLAVALGGYMMAGAANAINMVVDRDIDARMKRTAKRPTVTQRVSSRDALLFAFALAVLGFAVLWWGANLLAATLALMGLIWYVLVYTLYLKRRTWHNIVIGGAAGAFPPLVGWAAVTGELSLFAWYLFALIFFWTPVHFWALALMIQDDYRAVGVPMLPVVLGERATVIQIALYALLTALISLMPLLLGELGLLYLAASLLLNALLLLKSLALYRRPERRTAVSLYKYSMLYLALLFAAMAVDRAV