CMP-KDO synthetase catalyzes the activation of KDO which is an essential component of the lipopolysaccharide.
CMP-KDO Synthetase: 3-Deoxy-D-manno-octulosonate cytidylyltransferase (CMP-KDO synthetase) catalyzes the conversion of CTP and 3-deoxy-D-manno-octulosonate into CMP-3-deoxy-D-manno-octulosonate (CMP-KDO) and pyrophosphate. KDO is an essential component of the lipopolysaccharide found in the outer surface of gram-negative eubacteria. It is also a constituent of the capsular polysaccharides of some gram-negative eubacteria. Its presence in the cell wall polysaccharides of green algae and plant were also discovered. However, they have not been found in yeast and animals. The absence of the enzyme in mammalian cells makes it an attractive target molecule for drug design.
Jiyao W et al.(2023). "The conserved domain database in 2023.",