O-antigen group O:51 polymerase yielding a very long O antigen chain length (100 repeat units)
100.0 udcdpglcnac_a1_3_galnac_b1_3_gal_b1_3_glcnac_a1_4_glc_p ⇌ 99.0 udcpdp_p + OA51_VL_p