Energy-rich compounds play a fundamental role in cellular metabolism and energy transfer.
They can be classified based on their structure, functional roles, and mechanisms of energy storage or transfer.
1) Nucleotide-Based Energy Carriers
These compounds contain nucleotide structures and are primarily involved in energy transfer and signal transduction within cells.
A) Adenosine Triphosphate (ATP)
The universal energy currency of the cell.
Powers biological processes like muscle contraction, active transport, and biosynthesis.
B) Guanosine Triphosphate (GTP)
Similar to ATP but mainly involved in protein synthesis, signal transduction, and nucleic acid metabolism.
C) Cytidine Triphosphate (CTP)
Plays a role in phospholipid and RNA synthesis, contributing to membrane formation and genetic information transfer.
2) Reduced Coenzymes (Electron Carriers)
These compounds function as electron donors in redox reactions, facilitating energy production in metabolic processes.
A) Nicotinamide Adenine Dinucleotide (NADH)
A key electron carrier in glycolysis, the Krebs cycle, and oxidative phosphorylation.
B) Nicotinamide Adenine Dinucleotide Phosphate (NADPH)
Primarily involved in anabolic reactions, including fatty acid synthesis and antioxidant defense.
C) Flavin Adenine Dinucleotide (FADH₂)
Participates in the Krebs cycle and the electron transport chain, contributing to ATP production.
3) Phosphate-Based Energy Carriers
These molecules store energy in high-energy phosphate bonds, crucial for rapid energy transfer and storage.
A) Phosphocreatine
Acts as a quick energy reserve in muscle tissues, aiding ATP regeneration during intense activity.
B) 1,3-Bisphosphoglycerate (1,3-BPG)
A glycolytic intermediate that facilitates ATP generation during glycolysis.
4) Thioester-Based Energy Carriers
Thioester compounds are metabolic intermediates that transport acyl groups for various biochemical reactions.