GENERAL MICROBIOLOGY - T.P. Pirog - 2004

11. BASIC MECHANISMS OF METABOLISM AND ENERGY TRANSFORMATION IN MICROORGANISMS

11.5. PATHWAYS OF CATABOLISMS OF GLUCOSE AND OTHER CARBOHYDRATES

11.5.5. The Concept of "Key Enzymes"

How can we determine which glucose catabolic pathway operates in a particular microorganism? Naturally, it is necessary to measure the activities of Enzymes involved in Glucose Catabolism. However, Many enzymes catalyze glucose conversions across different Catabolic pathways of this substrate. For instance, hexokinase Functions in Glycolysis, the EDGP pathway, and The pentose phosphate cycle; glucose phosphate isomerase operates in glycolysis and the pentose phosphate cycle; glucose-6-phosphate dehydrogenase functions in the pentose phosphate cycle and the EDGP pathway, and so on.

However, there are enzymes that are unique to a specific metabolic pathway. These are known as Key Enzymes (Table 11.2).

Class="center">Table 11.3

Main PATHWAYS OF GLUCOSE catabolism in microorganisms

Catabolic pathway

Key enzymes

Embden–Meyerhof–Parnas (glycolysis, fructose-1,6-diphosphate pathway)

1 - Phosphofructokinase

6 - Phosphofructokinase

Entner–Doudoroff (KDPG pathway)

6 - Phosphogluconate dehydratase

2-Keto-3-deoxy-6-phosphogluconate aldolase

Cleavage via gluconate

NAD-glucose dehydrogenase NADP-glucose dehydrogenase PQQ-glucose dehydrogenase


Last update: 12/08/2026

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