Experiment 6A Enzyme Action: Testing Catalase Activity
Enzyme Action: Testing Catalase Activity Enzymes are proteins that serve as catalysts and accelerate chemical reactions in living organisms. Enzymes accomplish this by lowering the energy of activation of the organism it is acting upon, however enzymes will only lower the energy of activation for specific organisms, reducing chaotic chemical reactions. The reaction is carried out in it’s entirety in the active site of the enzyme. The substrate (organism acted upon), binds itself into the active site, of the enzyme, and the chemical process begins. The enzyme’s active site will reform itself for the substrate in order to form a perfect bond, this is called induced fit. This is only one of the changes that could occur to accommodate the substrate. For example, the enzyme might change the pH levels to promote the reaction.
There are numerous factors that can affect the rate of the chemical changes, four have the greatest affect. They are the concentration of the enzyme, the temperature, the pH level, and the salt concentration. The higher the concentration of the enzyme the faster the rate of change there is upon the organism. The temperature affects the rate in this way; each enzyme has a specific temperature in which it functions at an optimum rate, too low of a temperature, the enzyme will not function at all. However too high of a temperature produces the same results. Third, the pH level will affect the rate, H+ and OH- ions can cause the organism to change shape and become deformed, denature, and cause abnormal functionality. Finally, salt concentration will affect the rate of chemical change because the inorganic ions in salts will interfere with ionic bonds in protein molecules.
There are very few factors that influence the function of the enzyme. Some enzymes require cofactors, substances that assist the chemical reaction. Chemical inhibitors can inhibit the enzyme’s functionality (1) by atta...
Computer 6A Enzyme Action: Testing Catalase Activity
2A - Enzyme Action: Testing Catalase Activity
Enzyme Action: Testing Catalase ActivityIntroduction:Enzymes are proteins that serve as catalysts and accelerate chemical reactions in living organisms. Enzymes accomplish this by lowering the energy of activation of the organism it is acting upon, however enzymes will only lower the energy of activation for specific organisms, reducing chaotic chemical reactions. ...
Testing Catalase Activity (O - Vernier Software & Technology
To identify RpoS-dependent lacZ fusions, mutants containing individual random λplacMu insertions were conjugated with an Hfr strain containing an rpoS::Tn10 mutation that is transferred a few minutes after the point of origin during conjugation (). LacZ+ mutant strains that yielded transconjugants having reduced blue color on X-Gal-containing plates were considered to contain presumptive RpoS-dependent operon fusions. Of several hundred identified mutants, 105 could be efficiently complemented when transformed with an RpoS-expressing plasmid (determined by testing catalase activity in colonies grown on LB plates and flooded with 30% hydrogen peroxide). The fusion mutations were then transduced () into GC4468 for further study. A small proportion of the strains in the operon fusion mutant bank carried double fusions (∼2%). During conjugation, loss of a high-expressing lacZ+ allele by recombination occasionally produced transconjugants that were kanamycin resistant (due to retention of a second operon fusion) and possessed reduced lacZ activity. These strains were easily identified by the catalase complementation test and were not studied further. A diagrammatic representation of the protocol used to isolate mutants is shown in Fig. .