Catalyzes the hydrolysis of a carbon-carbon bond in 4,5: 9,10-diseco-3-hydroxy-5,9,17-trioxoandrosta-1(10),2-diene-4-oate (4,9-DSHA) to yield 9,17-dioxo-1,2,3,4,10,19-hexanorandrostan-5-oate (DOHNAA) and 2-hydroxy-hexa-2,4-dienoate (HHD). Also involved in biphenyl and polychlorinated biphenyls (PCBs) degradation