<p>CTP synthase is involved in pyrimidine ribonucleotide/ribonucleoside metabolism, catalysing the synthesis of CTP from UTP by amination of the pyrimidine ring at the 4-position [<cite idref="PUB00012378"/>]. The enzyme exists as a dimer of identical chains that aggregates as a tetramer. This gene has been found roughly 500 bp upstream of enolase in both beta (<taxon tax_id="915">Nitrosomonas europaea</taxon>) and gamma (<taxon tax_id="562">Escherichia coli</taxon>) subdivisions of Proteobacterium [<cite idref="PUB00007677"/>].</p>