. "The chemical reactions and pathways involving acetylene, a colorless, volatile, explosive gas, that occur in the absence of oxygen." . . . . "anaerobic acetylene catabolic process" . "anaerobic acetylene breakdown" . "anaerobic acetylene catabolism" . "anaerobic acetylene degradation" . "anaerobic ethyne catabolic process" . "anaerobic ethyne catabolism" . .