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Krebs cycle step 1
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(New page: <h2>First step: Citrate Synthase</h2> Image:citrate_3.jpg <p>Figure: Mechanism of the citrate formation</p> <p>In the first reaction (see Figure) of the Krebs cycle, acetyl-CoA react...) |
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| - | <h2>First step: Citrate Synthase</h2> | + | <h2>First step: [[Citrate Synthase]]</h2> |
[[Image:citrate_3.jpg]] | [[Image:citrate_3.jpg]] | ||
<p>Figure: Mechanism of the citrate formation</p> | <p>Figure: Mechanism of the citrate formation</p> | ||
| - | <p>In the first reaction (see Figure) of the Krebs cycle, acetyl-CoA reacts with oxal acetate. | + | <p>In the first reaction (see Figure) of the [[Citric Acid Cycle|Krebs cycle]], acetyl-CoA reacts with oxal acetate. |
Acetyl-CoA is coupled (yellow background) with the C2 atom of the oxal acetate and the C6 body | Acetyl-CoA is coupled (yellow background) with the C2 atom of the oxal acetate and the C6 body | ||
citryl-CoA is formed. This is a high-energy thioester bound in the enzyme, and it is not released. | citryl-CoA is formed. This is a high-energy thioester bound in the enzyme, and it is not released. | ||
In the second step of this reaction, the energy-rich thioester is hydrolyzed, and citrate and the coenzyme A (CoA-SH) were formed.</p> | In the second step of this reaction, the energy-rich thioester is hydrolyzed, and citrate and the coenzyme A (CoA-SH) were formed.</p> | ||
<p>The mechanism of the citrate synthase prevents premature and undesirable hydrolysis of acetyl-CoA, and, consequently, a waste of energy. </p> | <p>The mechanism of the citrate synthase prevents premature and undesirable hydrolysis of acetyl-CoA, and, consequently, a waste of energy. </p> | ||
Current revision
First step: Citrate Synthase
Figure: Mechanism of the citrate formation
In the first reaction (see Figure) of the Krebs cycle, acetyl-CoA reacts with oxal acetate. Acetyl-CoA is coupled (yellow background) with the C2 atom of the oxal acetate and the C6 body citryl-CoA is formed. This is a high-energy thioester bound in the enzyme, and it is not released. In the second step of this reaction, the energy-rich thioester is hydrolyzed, and citrate and the coenzyme A (CoA-SH) were formed.
The mechanism of the citrate synthase prevents premature and undesirable hydrolysis of acetyl-CoA, and, consequently, a waste of energy.
