Hydroxyornithine transacylase; part of the gene cluster that mediates the biosynthesis of hydroxamate-containing siderophores that play a critical role in virulence via intracellular iron acquisition during macrophage infection (PubMed:18404210). Siderophore biosynthesis. Targeted to peroxisomes via its PTS1-type peroxisomal targeting signal (By similarity). Expression is induced during iron deprivation and is regulated by the transcription factor SRE1 (PubMed:18404210, PubMed:22117028). Belongs to the lysine N-acyltransferase mbtK family.