Flashcards in 2.4 Cofactors & Coenzymes Deck (30):
What are cofactors and coenzymes?
Non protein components of enzymes
What is a cofactor?
Inorganic molecule or ion
What does a cofactor do?
Helps enzymes carry out their functions
How might a cofactor help an enzyme?
• transferring atoms of groups between reactions
• form part of active site helping enzyme and substrate bind
Are cofactors used up or changed in the reaction?
How are cofactors bound to proteins?
How do cofactors participate in catalysis?
By taking part in active site
What are coenzymes?
What does organic mean?
Do coenzymes participate in reaction?
Are coenzymes changed in reaction?
What do coenzymes act as in the reaction?
Moving chemical groups between enzymes
What are vitamins a source of?
Give an example of a cofactor and what it is used for:
Amylase requires them to form correctly shaped active site
What is the coenzyme Vit B5 used for?
To make coenzyme a used in breakdown of fatty acids and carbohydrates in respiration
What is the coenzyme Vit B3 used for?
To synthesise NAD - coenzymes responsible for transfer of H+ ions involved in respiration
What is a prosthetic group usually made of?
How is a mineral ion bound to a protein?
What do prosthetic groups form?
Permanent feature of protein
Zinc 2+ ions are a prosthetic group of what?
What is carbonic anhydrase?
Enzyme in red blood cells
Catalysed production of carbonic acid from water and carbon dioxide
What do Zinc 2+ ions in carbonic anhydrase form?
Permanent part of active site
What is the prosthetic group of haemoglobin?
How many polypeptide chains does haemoglobin have?
What does each polypeptide of haemoglobin have?
HAEM prosthetic group
What are inactive enzymes often called?
Inactive precursor enzymes
What are inactive precursor enzymes activated by?
Changes in tertiary structure particularly the active site
How is precursor activation ( change in tertiary structure) achieved?
Change in temp
Change in ph
addition of protease enzyme cofactor
What is an enzyme called before activation?