L10 Enzyme classes + membrane proteins Flashcards
How are enzymes classified?
Enzymes can be divided into different classes depending on the type of reaction they catalyse
What are Oxidoreductases?
Oxidation - reduction (electron transfer)
What are transferases?
Group transfer (Transfer of a functional group from one molecule to another)
What are Hydrolases?
Hydrolytic (Cleavage of bonds by the addition of water)
What are Lyases (synthases)?
Additional/removal of functional groups to form double bonds
What are Isomerases?
Intramolecular group transfer. Same formula, different arrangement
(Isomerisation)
What are ligases (synthetases)?
Formation of covalent bonds requiring ATP cleavage
During a chemical reaction, when an electron is lost by a molecule, what is the molecule described as?
Molecules is described as being oxidised
What is racemization?
When interconverting L-amino acids and D amino acids
Basically arranging their molecule arrangement
What does the dark wedges in a 3D model mean?
Coming towards you
What are the key properties of biological membranes? (3)
- Highly selective permeability for types of molecules and ions
- Fluid and asymmetric organisation
- Highly variable lipid and protein composition
What are biological membranes formed of?
They are largely composed of lipids and proteins
Can the types of lipids within a membrane influence its features?
The mixture of lipid types critically effects key properties such as fluidity, thickness and curvature of a membrane
What forms phospholipids?
Contain hydrophobic fatty acid chains
Various alcohols attached via a phosphate
What is membrane fluidity determined by?
Fatty acid composition and cholesterol content
