{"id":164,"date":"2019-04-10T11:24:28","date_gmt":"2019-04-10T11:24:28","guid":{"rendered":"http:\/\/biocp04.epgpbooks.inflibnet.ac.in\/?post_type=chapter&p=164"},"modified":"2019-04-10T12:06:55","modified_gmt":"2019-04-10T12:06:55","slug":"citric-acid-cycle","status":"publish","type":"chapter","link":"https:\/\/ebooks.inflibnet.ac.in\/biocp04\/chapter\/citric-acid-cycle\/","title":{"rendered":"Citric acid cycle"},"content":{"raw":"
\"epgp<\/a>\r\n<\/span><\/div>\r\n\u00a0 \u00a0<\/strong>\r\n\r\n \r\n\r\n \r\n\r\n \r\n\r\n \r\n\r\nObjectives<\/strong>\r\n
    \r\n \t
  1. History and introduction of citric acid cycle<\/li>\r\n \t
  2. Conversion of pyruvate to activated acetate by pyruvate dehydrogenase<\/li>\r\n \t
  3. Explain Reactions of citric acid cycle<\/li>\r\n \t
  4. Amphibolic nature of Citric acid cycle<\/li>\r\n<\/ol>\r\n\u00a0 \u00a0<\/strong>\r\n\r\n \r\n\r\nOVERVIEW<\/strong>\r\n\r\n\u00a0<\/strong>\r\n

    Citric acid cycle is also called Tricarboxylic acid (TCA) cycle<\/strong> or Krebs cycle<\/strong> is a sequence of biochemical reactions that occurs in all aerobic organisms for energy generation.<\/p>\r\n

    \u00a0<\/strong><\/p>\r\n

    Energy is generation is carried out by the oxidation of acetate, which is derived from carbohydrates, lipids and proteins converted into Co2 and chemical energy stored in the<\/p>\r\n

    \u00a0<\/strong><\/p>\r\n

    form of adenosine triphosphate (ATP). Furthermore the TCA cycle supplies precursors for synthesis of several amino acids and reducing agent such as NADH, which involves in various other biochemical reactions. TCA cycle is one of the initially established mechanism of cellular metabolism suggested by the central importance in various biochemical pathways.<\/p>\r\n \r\n

    The name of this biochemical pathway is derived from tricarboxylic acid (e.g. citric acid) . Citric acid is first utilized and then regenerated by this sequential reactions to complete the cycle. The major function of these two closely associated pathways is the oxidative breakdown of nutrients into production of usable energy in the form of ATP.<\/p>\r\n \r\n

    In eukaryotic cells, the Krebs cycle occurs in the mitochondrial matrix. In prokaryotic cells the TCA reaction occurs in the cytosol through the proton gradient for energy generation.<\/p>\r\n \r\n\r\nIn 1935 Albert Szent-Gyorgyi showed that\r\n\r\n \r\n\r\nSuccinate \u2192\u00a0Fumarate \u2192\u00a0Malate \u2192 Oxaloacetate\r\n\r\n \r\n\r\nCarl Martius and Franz Knoop showed\r\n\r\n \r\n

    \r\n\r\n\u00a0 \u00a0Citrate \u00a0cis-aconitate \u2192\u00a0 Isocitrate \u2192 \u03b1 ketoglutarate \u2192\u00a0 Succinate \u2192\u00a0\u00a0Fumarate \u2192\u00a0Malate \u2192\u00a0Oxaloacetate<\/span>\r\n\r\n<\/div>\r\n- Overall reaction of the citric acid cycle is:\r\n\r\n \r\n\r\n\"\"\r\n\r\n\"\"\r\n\r\n\"\"\r\n\r\n\"\"\u00a0<\/strong>\r\n\r\n2. Conversion of pyruvate to activated acetate by pyruvate dehydrogenase<\/strong>\r\n\r\n \r\n