SOD2 and infection: However, complex II driven state 3 and RCR were decreased by 43–44% and 34–65% respectively, by MnSOD deficiency (MnSOD+/- vs. WT, ap<0.05) or chronic Tc infection (WT.Tc vs. WT, bp<0.05), and MnSOD deficiency and Tc infection together resulted in >70% decline in complex II driven coupled respiration and RCR in the myocardium (Fig 3F & 3G, compare MnSOD+/-.