There&#x27;s some rather odd terminology use with this one.  A &quot;microbe&quot; is any living organism too small to be seen with the naked eye; so mostly single cell eukaryotes and prokaryotes.  Prokaryotes don&#x27;t have mitochondria.  But to read this article one would think it&#x27;s amazing that any microbe lacks mitochondria.  What&#x27;s interesting here is that they&#x27;ve apparently found a eukaryote which lacks mitochondria, (&quot;microbe&quot; need not have been mentioned).<p>I wish they&#x27;d also at least hint at endosymbiotic theory[1], which states that eukaryotic organelles, like mitochondria, may have at one time been separate organisms and became internal symbiotes later.  Then it becomes somewhat easier to be surprised at an eukaryote, an aggregate organism, lacking a critical component.<p>[1] <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Symbiogenesis" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Symbiogenesis</a>