SIRT5 and hyperinsulinemic hypoglycemia, familial, 4: To assess a potential overlap between these two drivers of protein succinylation, hyper-succinylated proteins and sites detected in fibroblasts from patients with SCL deficiency were compared with those in SIRT5 knockout (KO) mouse embryonic fibroblasts by Park et al.26; 102 proteins carry at least one succinylated lysine in both conditions, representing 41% of all proteins detected with hypersuccinylation due to SCL deficiency, or 29% of hyper-succinylated proteins detected due to deletion of SIRT5 (Fig. 3a).