The Iron-Sulfur Cluster Crisis: Why Your Mitochondria Can't Recover (And Why Practitioners Don't Talk About It) — The Colonocyte Trap: Fe-S Cluster Assembly Failure

Now combine these two failures: iron starvation + sulfur dysmetabolism. The colonocyte&#8217;s mitochondria can no longer assemble new Fe-S clusters. The enzymes responsible for cluster synthesis&#8212;including the ISCU complex&#8212;require both iron and sulfur-containing substrates. When either is missing, the system grinds to a halt. What happens next? Existing Fe-S clusters in Complex I, II, and III begin to degrade. They&#8217;re not permanent&#8212;they&#8217;re constantly turned over and recycled. Without replenishment, they rust out. Your colonocyte&#8217;s electron transport chain loses fidelity. Proton pumping becomes less efficient. Mitochondrial membrane potential declines. ATP production crashes. The colonocyte loses its primary energy source and its ability to maintain the tight junction barrier that keeps dysbiotic endotoxin at bay. This is the real pathophysiology of SIBO and chronic IBS that most practitioners never discuss.