Introduction to Metabolism - CLS4003-B - University of Bradford PDF

CLS4003-B Nutrition and Energy Introduction to metabolism 1 22 October, 2024 CLS4003-B Nutrition and Energy: Introduction to metabolism  Cellular metabolism Photosynthesis 2 22 October, 2024 CL...

CLS4003-B Nutrition and Energy Introduction to metabolism 1 22 October, 2024 CLS4003-B Nutrition and Energy: Introduction to metabolism  Cellular metabolism Photosynthesis 2 22 October, 2024 CLS4003-B Nutrition and Energy: Introduction to metabolism  Key things about metabolism Complicated Highly integrated – interconnection and interconversion Have production of reducing equivalents (NAD(P)H/FADH2), energy, building blocks for bio-molecules, or storage forms for later use ATP GTP UTP CTP , , energy , = molecules Have both exergonic (release energy/the free energy change for the reaction is negative – tends to be a spontaneous reaction) and endergonic (free energy change is positive – not spontaneous) reactions Support · cellular functions Vast majority of reactions are enzyme-catalysed 3 22 October, 2024 CLS4003-B Nutrition and Energy: Introduction to metabolism  What you need to know… NOT expected to be able to reproduce chemical structures ARE expected to know reaction sequences and key points (e.g. ATP and reducing equivalent use/production ARE expected to know key regulatory points in pathways ARE expected to know relevant metabolic diseases ARE expected to be able to apply you existing chemistry knowledge to this topic 4 22 October, 2024 CLS4003-B Nutrition and Energy: Introduction to metabolism  Reducing equivalents NAD+ reduction involves the reductant losing a hydride ion and a proton FAD+ undergoes sequential reduction by hydrogen addition 5 22 October, 2024 CLS4003-B Nutrition and Energy: Introduction to metabolism  A note on enzyme names… The reactions that occur in the production of NADH and FADH2 are oxidations of the reactants Thus the enzymes are technically oxidoreductases However, as these reactions involve the loss of hydrogen they are also known as dehydrogenases (catalyse oxidation - reduction reaction) 6 22 October, 2024 CLS4003-B Nutrition and Energy: Introduction to metabolism  Phosphorylation reactions Phosphorylation is a key metabolic event that can activate or destabilise a structure – making it more easy to metabolize compound further down the by forming unstable an pathway intermediate thatis easily broken down Think back to your chemistry knowledge – a phosphate group is large, relatively electronegative group that will distort hydrocarbon structures Distorts/destabluses the structure There is a wide range of phosphate donors, including ATP, GTP, UTP, and inorganic phosphate 7 22 October, 2024 CLS4003-B Nutrition and Energy: Introduction to metabolism  Thermodynamics This is a very complex topic – you are only expected to know what is on this slide!! To understand if a reaction will run spontaneously, biochemists discuss a thermodynamic quantity called delta G (ΔG) G= Gibbs free energy A = change If ΔG is negative – the reaction will tend to spontaneity If ΔG is positive – the reaction will not tend to spontaneity If ΔG is close to zero – the reaction is effectively at equilibrium This is important as it can help us understand how different reactions run, how they may be regulated, and how they may behave in terms of metabolic flux through a pathway 8 22 October, 2024 CLS4003-B Nutrition and Energy: Introduction to metabolism