Krebs Cycle Mnemonic

In this article, we will discuss the multiple Krebs Cycle Mnemonic for easy memorization of the steps of the krebs cycle. So let us first understand what is krebs cycle and the steps involved in krebs cycle.

The Kreb's Cycle is a series of biochemical reactions that occur in the mitochondria of eukaryotic cells.It can also be referred to as the citric acid cycle or the tricarboxylic acid (TCA) cycle. The cycle plays a crucial role in the oxidative metabolism of carbohydrates, fats, and proteins, generating energy in the form of ATP and producing precursor molecules for the synthesis of amino acids and other biomolecules. Here are the steps of the Krebs Cycle:

1. Acetyl-CoA Formation: The cycle begins when a two-carbon molecule derived from pyruvate, known as acetyl-CoA, combines with a four-carbon molecule called oxaloacetate, forming citrate. Citric synthase is the enzyme that catalyzes this process.

2. Isomerization of Citrate: Citrate, the product of the first step, is converted into its isomer, isocitrate, through the action of the enzyme aconitase.

3. α-Ketoglutarate Formation: Isocitrate undergoes oxidative decarboxylation, resulting in the formation of α-ketoglutarate and the release of carbon dioxide (CO2). This reaction is catalyzed by the enzyme isocitrate dehydrogenase, and it also generates NADH.

4. Succinyl-CoA Formation: α-Ketoglutarate is oxidatively decarboxylated to form succinyl-CoA, another two-carbon compound, along with the release of CO2 and the generation of NADH. The enzyme responsible for this reaction is α-ketoglutarate dehydrogenase complex.

5. Succinate Formation: Succinyl-CoA is then converted into succinate through a series of enzyme-catalyzed reactions. In this step, a molecule of GTP (guanosine triphosphate) is produced by substrate-level phosphorylation. The enzyme succinyl-CoA synthetase is involved in this reaction.

6. Fumarate Formation: The enzyme succinate dehydrogenase helps oxidize succinate to produce fumarate. This reaction also generates FADH2.

7. Malate Formation: The enzyme fumarase catalyzes the reaction between fumarate and hydration to create malate.

8.Regeneration of Oxaloacetate: Oxidizing malate yields oxaloacetate, the four-carbon molecule needed for the first part of the cycle. NADH is also produced by this reaction, which is aided by malate dehydrogenase.

The oxaloacetate generated in the last phase of the Krebs Cycle can then combine with another acetyl-CoA molecule to restart the cycle after completing all eight steps.

Krebs Cycle Mnemonic

Mnemonic 1: "Can I Keep Some Secrets From My Own?"

• Citrate
• Isocitrate
• α-Ketoglutarate
• Succinyl-CoA
• Succinate
• Fumarate
• Malate
• Oxaloacetate

• Can
• I
• Keep
• Some
• Secrets
• From
• My
• Own

Mnemonic 2: "Can I Keep Some Salt For My Omelette?"

• Citrate
• Isocitrate
• α-Ketoglutarate
• Succinyl-CoA
• Succinate
• Fumarate
• Malate
• Oxaloacetate

• Can
• I
• Keep
• Some
• Salt
• For
• My
• Omelette

Mnemonic 3: "Can I Keep Some Snacks For My Outing?"

• Citrate
• Isocitrate
• α-Ketoglutarate
• Succinyl-CoA
• Succinate
• Fumarate
• Malate
• Oxaloacetate

• Can
• I
• Keep
• Some
• Snacks
• For
• My
• Outing