O-antigen group O:40 polymerase yielding a very long O antigen chain length (100 repeat units)
100.0 udcdpgalnac_b1_3_glc_b1_4_man_b1_2_glcnac_a1_3_galnac_p ⇌ 99.0 udcpdp_p + OA40_VL_p