• a cofactor responsible for carbon dioxide transfer in several carboxylase enzymes- carboxylation
• requires ATP

[image]

• PLP acts as a coenzyme in all transamination reactions, and in some decarboxylation and deamination reactions of amino acids.
• [image]
• The aldehyde group of PLP forms a Schiff-base linkage (internal aldimine) with the ε-amino group of a specific lysine group of the aminotransferase enzyme
• beta-elimination reactions
• phosphorylysis also

Thiamine pyrophosphate

• thiamine (vitamin B₁) derivative which is produced by the enzyme thiamine pyrophosphatase
• The C2 of this ring is capable of acting as an acid by donating its proton and forming a carbanion
• catalyses the reversible cleavage of a substrate compound at a carbon-carbon bond connecting a carbonyl group to an adjacent reactive group (usually a carboxylic acid or an alcohol)
• used for alpha-decarboxylation

[image]can be deprot to form carbanion and act as general acid...called ylid form (+/-)

• can be found in:
• Pyruvate dehydrogenase complex
• Pyruvate decarboxylase complex in ethanol fermentation
• Alpha-ketoglutarate dehydrogenase complex

[image]

• As lipoamide, it is a cofactor in the multienzyme complexes which catalyze the oxidative decarboxylation of a-keto acids such as α-ketoglutarate and pyruvate
• can be a carrier of both hydrogen and acetyl (or other acyl) groups
• used for redox reaction
• found in: PDH complex

• central component of the cofactors FAD and FMN
• used for carbon carbon desaturation and redox
  
• oxidizing agents because of their ability to accept a pair of hydrogen atoms[image]
• Flavoproteins play roles in the electron transport chain
• Decarboxylation of pyruvate and α-ketoglutarate
• Fatty acyl CoA dehydrogenase requires FAD in fatty acid oxidation
• FAD is required to the production of pyridoxic acid from pyridoxal (vitamin B₆)
• The primary coenzyme form of vitamin B₆ requires FAD (pyridoxal phosphate) is FMN dependent

• [image]
• niacin is incorporated into nicotinamide adenine dinucleotide (NAD)
• NAD+ and NADP+ are coenzymes in a wide variety of enzymatic oxidation-reduction reactions