Catalyzes the deacetylation of N-acetyl-L-citrulline to produce L-citrulline. This is a step in an alternative arginine biosynthesis pathway (PubMed:16585758, PubMed:16511126). Is also able to catalyze the deacetylation of N-acetylornithine in vitro, with almost equal velocity. However, this reaction may be not relevant in vivo since Xanthomonas does not possess the canonical argF gene and cannot convert ornithine to citrulline via ArgF' (PubMed:16585758). H2O + N(2)-acetyl-L-citrulline = acetate + L-citrulline H2O + N(2)-acetyl-L-ornithine = acetate + L-ornithine Binds 1 Co(2+) ion per subunit. Amino-acid biosynthesis; L-arginine biosynthesis. Forms homodimers in the crystal, but higher order oligomers may form in solution. Consists of two domains, a catalytic domain (formed by residues 1-166 and 286-365 from the N and C termini, respectively) and a dimerization domain (residues 167-285). Belongs to the peptidase M20A family. N-acetylcitrulline deacetylase subfamily.