ID 4.4.1.2 DE homocysteine desulfhydrase. AN homocysteine desulfurase. CA H2O + L-homocysteine = 2-oxobutanoate + H(+) + hydrogen sulfide + NH4(+). CC -!- The enzyme cleaves a carbon-sulfur bond, releasing hydrogen sulfide CC and an unstable enamine product that tautomerizes to an imine form, CC which undergoes a hydrolytic deamination to form 2-oxobutanoate and CC ammonia. CC -!- The latter reaction, which can occur spontaneously, can also be CC catalyzed by EC 3.5.99.10. DR Q55DV9, CGL_DICDI ; P32929, CGL_HUMAN ; Q60HG7, CGL_MACFA ; DR Q8VCN5, CGL_MOUSE ; Q19QT7, CGL_PIG ; P18757, CGL_RAT ; DR O05394, MCCB_BACSU ; Q8RDT4, MEGL_FUSNN ; Q8L0X4, MEGL_FUSNP ; DR Q7MX71, MEGL_PORGI ; P13254, MEGL_PSEPU ; Q826W3, MEGL_STRAW ; DR Q73KL7, MEGL_TREDE ; //