Activates KDO8N (a required 8-carbon sugar) for incorporation into bacterial lipopolysaccharide in the Shewanella genus. 8-amino-3,8-dideoxy-alpha-D-manno-octulosonate + CTP = CMP-8-amino-3,8-dideoxy-alpha-D-manno-oct-2-ulosonate + diphosphate Bacterial outer membrane biogenesis; lipopolysaccharide biosynthesis. Belongs to the KdsB family.