Biochemistry - Lecture 1 Flashcards
What metabolic pathways are preserved across different kingdoms?
glycolysis
photosynthesis
Describe the energy of catabolism
energy yielding
describe the energy of anabolism
energy requiring
What is a redox reaction?
a chemical reaction allowing for the transfer of energy via the movement of electrons/ hydrogen (OIL RIG)
what does the oxygenation of a bond say about the energy in those bonds, and the number of hydrogens?
more oxidised = more energy in bonds, bet less hydrogens
What is the relationship between the energy released from catabolism and the energy required for anabolism?
energy released is less than the energy required for anabolism
What does anabolism provide in the body?
biological building blocks
How can catabolism and anabolism be regulated?
- enzymes provide tight regulation
- ATP hydrolysis improves thermodynamic unfavourability of anabolism
What are enzymes? What are their functions?
proteins,
- catalyse specific reactions,
- reduce the free energy of activation
What are the 3 characteristics of enzymes?
- catalytic power
- specificity
- regulation
What is the function of a kinase?
uses ATP to phosphorylate a substrate. uses magnesium as a co-factor
What is the function of a phosphorylase?
adds PO4(^3-) group using free PO4(^3-). symbol is Pi
What is the function of a isomerase?
converts one isomer to another (same formula, different structure) eg. glucose to fructose
What is the function of epimerase?
creates an epimer (same formula and function, but vary around one carbon molecule)
What is the function of a mutase?
moves groups of atoms within the substrate
What is the function of a transferase?
moves a side chain from one substrate to another
What is the function of a lyase?
breaks a carbon-carbon bond
What is the function of a carboxylase?
makes a carbon-carbon bond (uses CO2 for this). uses biotin as a co-factor
What is the function of a synthase?
no bonds broken, substrates converted to products without the input of energy (no ATP).
What is the function of a synthetase?
same as synthase, but requires ATP
What is the function of a dehydrogenase?
involves a co-factor in the reaction (NAD, NADH, etc.) 2 H atoms are removed from the substrate
What is the function of a hydrolase?
uses water to break the bond
What does an enzyme do if ‘thio’ is in the name?
a sulfur bond is broken
The enzymes within a pathway are associated together, and can be…?
- separate (diffuse substrates)
- multi-enzyme complexes
- membrane bound
What is an amphibolic intermediate?
intermediates that are in both anabolic and catabolic metabolism pathways
What are 3 key molecules for linking reactions?
- glucose-6-phosphate (G6P)
- pyruvate
- Acetyl-CoA
What are some key metabolites formed from G6P?
- glycogen
- pyruvate
- ribulose-5-phosphate
