The glyoxylate bypass uses two key enzymes — isocitrate lyase and malate synthase — to convert isocitrate → succinate + glyoxylate, then glyoxylate + acetyl-CoA → malate, without losing CO₂. This allows net synthesis of C₄ oxaloacetate from C₂ acetyl-CoA, replenishing TCA intermediates for biosynthesis. It is essential for growth on acetate, ethanol, or fatty acids.