Which of the following statements about the Entner-Doudoroff pathway is false?
a. It is a series of reactions that synthesizes glucose.
b. Its products are sometimes used to determine the presence of Pseudomonas.
c. It is a pathway of chemical reactions that catabolizes glucose.
d. It is an alternative pathway to glycolysis.

Verified step by step guidance

1. Step 1: Understand the Entner-Doudoroff (ED) pathway. It is a metabolic pathway used by some bacteria to break down glucose, so it is involved in catabolism, not synthesis.
2. Step 2: Analyze option (a): 'It is a series of reactions that synthesizes glucose.' Since the ED pathway breaks down glucose rather than synthesizing it, this statement is likely false.
3. Step 3: Consider option (b): The ED pathway products can be used as biochemical markers to identify certain bacteria like Pseudomonas, so this statement is true.
4. Step 4: Review option (c): The pathway catabolizes glucose, meaning it breaks glucose down to extract energy, so this statement is true.
5. Step 5: Evaluate option (d): The ED pathway is an alternative to glycolysis (Embden-Meyerhof-Parnas pathway) for glucose catabolism, so this statement is true.

Key Concepts

Entner-Doudoroff Pathway

The Entner-Doudoroff pathway is a metabolic route used by some bacteria to break down glucose into pyruvate and glyceraldehyde-3-phosphate. It serves as an alternative to the more common glycolysis pathway and is involved in glucose catabolism, not synthesis.

Glucose Catabolism vs. Glucose Synthesis

Glucose catabolism refers to the breakdown of glucose molecules to release energy, while glucose synthesis involves creating glucose from smaller molecules. The Entner-Doudoroff pathway is involved in catabolism, meaning it degrades glucose rather than synthesizing it.

Microbial Identification Using Metabolic Pathways

Certain metabolic pathways and their products can be used as biochemical markers to identify specific bacteria. For example, the presence of the Entner-Doudoroff pathway and its products can help detect bacteria like Pseudomonas, which utilize this pathway uniquely compared to other microbes.