Enzyme substrate complex

all discussions related enzyme complex and theories related.

1. BioChemicalEngineering The enzyme substrate complex and enzyme action By: AdnanALIjatoi 14CH20 13-03-2017 1

2. Contents : Aims and objectives Enzyme Enzyme substrate Enzyme substrate complex Enzyme action Quotation END 13-03-2017 2

3. Aims and Objectives You will be aware about enzyme, substrate and their actions Concept behind the enzyme substrate complex and enzyme action 13-03-2017 3

4. Enzyme : Enzymes  are biological molecules (proteins) that act as catalysts and help complex reactions occur everywhere in life . Enzymes are made from  amino acids , and they are  proteins . When an enzyme is formed, it is made by stringing together between 100 and 1,000  amino acids  in a very specific and unique order. The chain of  amino acids  then folds into a unique shape . Enzymes  are biological molecules (typically proteins) that significantly speed up the rate of virtually all of the chemical reactions that take place within cells. They are vital for life and serve a wide range of important  functions  in the body, such as aiding in digestion and metabolism. 13-03-2017 4

5. Enzyme Substrate In biochemistry, the  substrate  is a molecule upon which an enzyme acts. Enzymes catalyze chemical reactions involving the  substrate (s). In the case of a single  substrate , the  substrate  bonds with the enzyme active site, and an enzyme- substrate  complex is formed . 13-03-2017 5

6. Enzyme substrate complex A non-covalent complex composed of a substrate bound to the active site of the enzyme . The enzyme-substrate complex is formed during a chemical reaction. The substrate may still dissociate from the enzyme. The enzyme may then be recycled and combined with another substrate to form the complex . The substrate bonds to a small area of the enzyme termed the  active site . When the enzyme is bonded to the substrate, we call this the  enzyme-substrate complex . Once the reaction is complete, the enzyme releases the product and is ready to bond with another substrate. 13-03-2017 6

7. Continue.. A theory to explain the catalytic action of enzymes was proposed by the Swedish chemist Savante Arrhenius in 1888. He proposed that the substrate and enzyme formed some intermediate substance which is known as the enzyme substrate complex. The reaction can be represented as : 13-03-2017 7

8. Continue.. Enzymes are only able to function if they bond with the correct substrate. E nzymes are highly selective; they'll activate with one and  only  one particular substrate .  how do they know whether or not the molecule next to them is the substrate that they want?  Two models attempt to explain this . 1.Lock and Key Model 2. Induced Fit Model 13-03-2017 8

9. 1.Lock and Key Model In the lock and key model, the substrate and the enzyme's active site are exact matches for each other, similar to puzzle pieces fitting together. Only a single substrate is the 'key' that matches the 'lock' of the active site. Once the enzyme locates the molecule that fits it exactly, the chemical reaction begins. After the products are released, the enzyme searches for another molecule that is an exact match . 13-03-2017 9

10. 2. Induced Fit Model The  induced fit model  is a modification of the lock and key model and is generally thought to be the more accurate version. In this representation, the active site is not an exact fit for the substrate. Rather, the substrate induces a change in the enzyme, causing it to modify its shape until the binding is complete. 13-03-2017 10

11. Enzyme Action Enzymes accelerate the rates of reactions while experiencing no permanent chemical modification as a result of their participation . Enzymes can accelerate, often by several orders of magnitude, reactions that under the mild conditions of cellular concentrations, temperature,  p  H, and pressure would proceed imperceptibly (or not at all) in the absence of the enzyme . The efficiency of an enzyme's activity is often measured by the turnover rate, which measures the number of molecules of compound upon which the enzyme works per molecule of enzyme per second . Carbonic anhydrase, which removes carbon dioxide from the blood by binding it to water, has a turnover rate of 10 6 . That means that one molecule of the enzyme can cause a million molecules of carbon dioxide to react in one second . Most enzymatic reactions occur within a relatively narrow temperature range (usually from about 30°C to 40°C ) 13-03-2017 11

12. Four Steps of Enzyme Action 1. The enzyme and the substrate are in the same area. Some situations have more than one substrate molecule that the enzyme will change. 2. The enzyme grabs on to the substrate at a special area called the active site. The combination is called the enzyme/substrate complex. Enzymes are very, very specific and don't just grab on to any molecule. The active site is a specially shaped area of the enzyme that fits around the substrate. The active site is like the grasping claw of the robot on the assembly line. It can only pick up one or two parts.  3 . A process called catalysis happens. Catalysis is when the substrate is changed. It could be broken down or combined with another molecule to make something new. It will break or build chemical bonds. When done, you will have the enzyme/products complex .   4. The enzyme releases the product. When the enzyme lets go, it returns to its original shape. It is then ready to work on another molecule of substrate 13-03-2017 12

13. Question may be asked that Can WE Control Them? There are many factors that can regulate enzyme activity, including temperature, activators,  pH  levels, and inhibitors. 13-03-2017 13

14. QUOTATION Looking at Mirror Everyday Un-cover many things about ourselves AdnanALIJatoi 13-03-2017 14