Mitochondria produce proteins that start with formyl methionine, which can be sensed by the immune system as a sign of infection when they escape the mitochondria.

“just remember those 13 proteins that are made by the mtDNA the translation of those 13 proteins resembles the translation of bacterial proteins and bacterial protein translation doesn't begin with a methanol tyranny it begins with the formal but I know tyranny remember this yeah this is my god I feel like I'm back in medical school can you just just for no other reason than for me to remember that let's go through that so your your DNA makes your messenger RNA your messenger RNA then moves over to be translated and to actually have the amino acids put in place to resemble the code that's being said so talk about where the meth terminal and shows up there in you and I in eukaryotes protein translation begins with thiamine residue in bacteria it's not a simple methionine but it's a it's a modified molecules called formyl methionine and first order approximation it's almost a signature of a bacterial derived protein and we actually have receptors that are designed to detect formylated peptides it's a sign of some sort of an infection”