<prompt> 3 ATP;s are formed in the following steps of Kreb;s cycleIsocitrate dehydrogenaseSuccinate dehydrogenaseSuccinate thiokinaseMalate dehydrogenase  <response>: 3rd Step: Formation of Alpha-Ketoglutarate i. This reaction is a two-step process, both catalyzed by the same enzyme, isocitrate dehydrogenase Step 3, Fig.18.2. In the first pa of the reaction, isocitrate is dehydrogenated to form oxalosuccinate. It is an unstable compound which undergoes spontaneous decarboxylation to form alpha-ketoglutarate. ii. The NADH generated in this step is later oxidized in electron transpo chain ETC to generate 3 ATPs. iii. Isocitrate 6 carbons undergoes oxidative decarboxylation to form alpha-ketoglutarate 5 carbons. In this reaction, one molecule of CO2 is liberated. iv. The isocitrate dehydrogenase has isoenzymes; the mitochondrial form utilizes NAD, while cytoplasmic enzyme is NADP dependent.Ref: MN Chatterjea Textbook of Medical Biochemistry, 6th edition, page no: 218 