Acyl-CoA dehydrogenase, that exhibits maximal activity towards saturated C22-CoA. Probably participates in beta-oxydation and energy production but could also play a role in the metabolism of specific fatty acids to control fatty acids composition of cellular lipids in brain. a 2,3-saturated acyl-CoA + H(+) + oxidized [electron-transfer flavoprotein] = a (2E)-enoyl-CoA + reduced [electron-transfer flavoprotein] docosanoyl-CoA + H(+) + oxidized [electron-transfer flavoprotein] = (2E)-docosenoyl-CoA + reduced [electron-transfer flavoprotein] H(+) + oxidized [electron-transfer flavoprotein] + tetracosanoyl-CoA = (2E)-tetracosenoyl-CoA + reduced [electron-transfer flavoprotein] eicosanoyl-CoA + H(+) + oxidized [electron-transfer flavoprotein] = (2E)-eicosenoyl-CoA + reduced [electron-transfer flavoprotein] H(+) + hexacosanoyl-CoA + oxidized [electron-transfer flavoprotein] = (2E)-hexacosenoyl-CoA + reduced [electron-transfer flavoprotein] H(+) + oxidized [electron-transfer flavoprotein] + tricosanoyl-CoA = (2E)-tricosenoyl-CoA + reduced [electron-transfer flavoprotein] Lipid metabolism; fatty acid beta-oxidation. Homodimer. Belongs to the acyl-CoA dehydrogenase family.