By Marian and Emma-Rose ENZYMES By Marian and Emma-Rose I found a useful site for information and diagrams:https://www.bbc.co.uk/education/guides/zdt4jxs/revision/1

The Role of Enzymes 1)To help chemical reactions to occur / to affect or modify the rate of chemical reactions. Reactions can still occur without the presence of enzymes but it would not be fast enough to support life. Enzymes are organic catalysts that are the principal regulators of most chemical activity in living systems Catalysts are substances that bring about reaction without being changed itself chemical reactions requires specific enzymes

STRUCTURE Large complex proteins Protein Nature Active site Tip: Names of Enzymes often end in “-ase”. Large complex proteins One or more polypeptide chains Made of amino acids Protein Nature Either exclusively proteins or proteins with non-protein parts Coenzymes vitamins Active site Enzyme molecules are larger than what they interact with The way the chains fold results in formation of pockets Reacting molecules fit into THIS IS THE ACTIVE SITE

Enzyme Substrate Complex For an enzyme to affect rate of reaction Enzyme must form temporary association with substance(s) whose reaction rate it affects Substrates Association between enzyme and substrate thought to involve close, physical association between molecules Enzyme-substrate complex As enzyme substrate forms enzyme action takes place Completion of reaction Enzyme and products separate Enzyme molecule now available to form additional complexes Although enzymes may be reused in cells, they eventually are destroyed and new ones must be synthesized

Function: -Evidence has accumulated so there can be a model made of enzyme action -Scientists don’t exactly know how enzymes work so they use models to infer -Useful in visualising the nature of its function - Is consistent with available evidence function There are two different models that show inferences of the enzyme functions. “Lock and Key” Model Induced Fit Model

“Lock and Key” Model The Lock and Key model shows that enzymes can only interact with specific substrates. Like a lock and key only one kind of substrate can fit into a certain enzyme.

Induced Fit Model The induced fit model show that the enzymes can change their shape in order to better fit the substrate it is with.

Some Factors Affecting Enzyme Action Small amounts of enzyme can cause reaction of large quantities of substrate For enzyme-substrate complex to form and reaction to occur is short 1 enzyme molecule can catalyze thousands of substrate reactions each second The enzyme can only perform one reaction at a time Enzymes enable cell reactions to take place at normal temperatures Many chemical reactions take place slowly at regular temperatures Can be speeded up raising temperature High temperatures can kill living cells Enzymes speed up reactions without high temperatures Enzymes work best at certain temperature If at low temperature reaction is slow If at high temperature reaction forms at faster rate but enzyme starts to break down Denaturation Optimum temperature is where enzyme is most effective Close to normal cell temperature

Factors that Influence Enzymes Enzymes do not have a fixed rate of reaction time. Certain environmental factors affect the way the rate of enzyme action. Some factors that vary the rate of enzyme action are pH, temperature and relative amounts of enzyme and substrate.

Review Questions: b) False An enzyme speeds up chemical reaction in the cell, but can only be used once. 2) An enzyme can bind only one reactant at a time. 3) Which of the following can only bind to the active site of an enzyme? 4) Enzymes are ____. 5) Enzymes are inorganic. True b) False True b) False lipids b) any other enzyme c) Product d) substrate Lipids Carbohydrates Nucleic Acids True b) False d) Proteins

About the Food Sugars in grapes The enzyme sucrase digests glucose Fructose The enzyme sucrase digests glucose

Links to pictures http://www.bioprocessintl.com/manufacturing/formulation/key-aspects-of-enzyme-activity-and-steady-state-kinetics-320908/ background https://www.texasgateway.org/resource/enzymes diagram http://study.com/academy/lesson/induced-fit-enzyme-model-definition-theory-quiz.html diagram https://www.pinterest.com/pin/500884789789588041 diagram https://www.redbubble.com/people/amoebasisters/works/22618959-enzyme-and-substrate-love-story?p=sticker diagram https://www.bbc.co.uk/education/guides/zdt4jxs/revision/4 - tempature graph https://alevelnotes.com/Factors-affecting-Enzyme-Activity/146- pH https://bio.libretexts.org/Under_Construction/BioStuff/BIO_101/Reading_and_Lecture_Notes/Energy%2C_Enzymes%2C_Metabolism - Substrate concentration https://news.christianacare.org/2017/04/christiana-care-and-thomas-jefferson-university-launch-new-genetic-counseling-masters-degree-program/ background http://glutathionepro.com/what-is-glutathione-s-transferase/ background http://ascensionenergies.com/2016/09/30/scientists-change-dna-with-frequency-experiments/ background http://sciencenordic.com/new-study-shatters-established-knowledge-immune-system background https://biologydictionary.net/enzyme-substrate-complex/ diagram https://wall.alphacoders.com/big.php?i=465168 background