Just recently, a systematic method of classifying and naming enzymes has been established now by the name and type of reaction of reaction as well as indicating the reaction it catalyzes. There are six main classes of enzymes. These enzymes are oxidoreductases, and the reaction catalyzed is oxidation – reduction reactions, transferases, and the reaction catalyzed transfer a group between two compounds, hydrolases - is a hydrolysis reaction, lyases – add or remove groups involving a double bond without hydrolysis, iomerases – rearrange atoms in a molecule to form an isomer, ligases – form bonds between molecules using ATP energy. Examples of the classes of enzymes: Oxidases oxidize substances. Reductases reduce a substance. Deyhdrogenases remove 2 h atoms to form a double bond. Transaminases transfer amino groups. Kinases transfer phosphate groups. Proteases hydrolyze peptide bonds. Lipases hydrolyze ester bonds in lipids. Carbohydrases hydrolyze phosphate-ester bonds. Nucleases hydrolyze nucleic acids. Carboxylases add CO2. Deaminases NH3-. Isomersases convert cis to trans, or reverse. Epimerases convert D to L isomers, or reverse. Synthetases combine two molecules.
The action of enzymes are all almost globular proteins. All enzymes have a very unique three- dimensional shape that recognizes and binds a small group of reacting molecules that are called substrates. The structure of the enzyme plays an important role in how that enzyme catalyzes reactions. A typical enzyme is much larger than its substrate. However, there is a region called the active site where the enzyme binds a substrate or substrates and catalyzes the reaction. The active site is a small little pocket that fits the structure of the substrate. The active site of a particular enzyme fits the shape of only a few types of substrates, which makes enzymes very specific about the type of substrate they bind.
Enzymes has an activity process which describes how fast an enzyme catalyzes the reaction that converts a substrate to product. Enzymes are sensitive to temperature. In being sensitive to temperature they show a small amount of activity at low temperatures because there is not enough sufficient amount of energy. Enzymes activity plays a great role in increased temperatures, meaning reacting molecules move faster to cause more collisions with enzymes. Doing a simple kitchen experiment yourself you can see the activity of enzymes. You would be able to see with your own eyes the activity of enzymes if you were to slice an apple or banana. You would see that the enzyme activity of the apple is much slower than the enzyme activity of the banana. Enzymes are most active at optimum temperature at 37°C or body temperature for most enzymes. At temperatures above 50°C, the tertiary structure and thus the shape of most proteins is destroyed, which causes a loss in enzyme activity. Hospitals and labs, for example uses autoclaves where the high temperatures denature the enzymes in harmful bacteria. Sine the risks spreading of infections is high in places of sick people this cuts down the spread of nosocomial infections in healthcare settings. After instruments or devices are sterilized or cleaned they are immediately wrapped in a sterile towel or put into a sterilized container fro proper storage. It is important to maintain a sterile field when using these sterilized devices or instruments to cut down the spread of bacteria.
Enzymes in most cells have optimum pH values at physiological pH values around 7.4. However, the stomach have a low optimum pH because the hydrolyze proteins at the acidic pH in the stomach. Take this for example pepsin, which is a digestive enzyme in the stomach, has an optimum pH of two. Between meals, the pH in the stomach is four or five and pepsin shows little or no digestive activity. When food enters the stomach, the secretion of HCl lowers the pH to about two, which activates pepsin. When small changes of pH are corrected, an enzyme will regain its structure and activity. However, large variations from optimum pH permanently destroy the structure of the enzyme.
Enzymes are proteins which regulate (speed up) chemical reaction within the cell without extra heat or energy. They lower the activation energy required for a given chemical reaction to take place. Enzymes are made up of hundreds to thousands of amino acids connected together by dehydration synthesis. They are proteins which have a unique three-dimisional shape, this is important for their function. The must fit the molecule they interact with. A common enzyme ending for an enzyme is “ase.” An example would be lipase which is an enzyme that splits lipids. It must fit the molecule it is working on also. The molecule and enzyme works on is called a substrate. If the three- dimensional shape of a protein changes it is considered to be denatured. (Biology Third Edition, David Krough)
When spoken above of the autoclave, the autoclave is meant to break or change the shape of bacteria causing enzymes to denature or destroy them. The enzyme will change and the enzyme will not fit the substrate. Meaning no chemical reaction will take place at all. The enzymes are called organic catalyst and they are not used up in the reactions they regulate. They can be used over and over again. Enzymes can drive a chemical reaction both ways depending on the needs of the cell. They can connect smaller molecules to form a larger molecule (dehydration synthesis). They can also take a large molecule and split it into smaller molecules (hydrolysis). The turn over number is the reaction per minute that an enzyme can regulate. This can be as high as 100,000 reactions per minute.
Enzymatic inhibition – a fake substrate will tie up enzymes which regulate certain chemical reaction. The false substrate looks normal but when the enzymes grab it, the enzymes can not let go. The enzyme is inactivated because it can’t release the fake substrate and complete it reaction. Insecticides are an example of a fake substrate. In speaking of enzymes we see that there are many different enzymes and they all have many different functions to our every day life. I can say I’ve learn a lot about enzymes is doing my research and reading up on certain materials.
