On comparative pathogenomics

I have performed synteny based comparison of a pathogenome of interest (say X) against the remaining strains of same group. I have then performed domain analysis of putative genes of X and have considered genes which are unique in relation to other strains of the same group. Finally among these unique proteins, I got Ankyrin repeat (ANK) where I want to focus on. Literature says that pathogens have evolved by incorporating such repeats (ANK) from eukaryotic hosts as they help in inducing pathogenesis to the host. It is also seen that the ANK in pathogen X has an ortholog in host (with Divergence=0.8, BLAST E-value=1e-5), possibly this might be due to HGT events.

So now my query is how can I trace this HGT event from eukaryote to prokaryote with a bioinformatic approach to prove that X has obtained ANK repeat from the host organism? Or is there any other way to continue with, other then to prove the HGT event, for a publication.