tricarboxylic acid cycle KEGG:map00072 KREBS cycle UPa:UPA00223 KEGG:map00630 KEGG:map00650 KEGG:map01100 KEGG:map01120 GO:0006099 The tricarboxylic acid cycle (citric acid cycle, TCA cycle, Krebs cycle, or rarely, the Szent-Gyorgyi-Krebs cycle) is a series of enzyme-catalysed chemical reactions of central importance in all living cells that use oxygen as part of cellular respiration. pathway KEGG:map00480 KEGG:map00280 KEGG:map00720 KEGG:map00620 KEGG:map00640 KEGG:map01110 KEGG:map00020 KEGG:map00680 TCA cycle KEGG:map00710 citric acid cycle carbohydrate metabolism