Chymotrypsin Essay

Of the thousands of enzymes known, there is a family of enzymes called proteases that catalyze a reaction of breaking down proteins. What do you think would happen if you added a protease to your sample of catalase before proceeding with your experiment?

Of the many functions of proteins, catalysis is by far the most vital. When catalysis is not present, most reactions in the biological systems take place very slowly to produce at an adequate pace for metabolising organism. The catalysts that take this role are called enzymes. Enzymes are the most efficient catalysts; they can enhance rate of reaction by up to 1020 over uncatalysed reactions. (Campbell et al, 2012).

Enzymes are biological catalysts that speed up chemical reactions, without being used up or changed. Catalase is a globular protein molecule that is found in all living cells. A globular protein is a protein with its molecules curled up into a 'ball' shape. All enzymes have an active site. This is where another molecule(s) can bind with the enzyme. This molecule is known as the substrate. When the substrate binds with the enzyme, a product is produced. Enzymes are specific to their substrate, because the shape of their active site will only fit the shape of their substrate. It is said that the substrate is complimentary to their substrate.

These results shown from this experiment led us to conclude that enzymes work best at certain pH rates. For this particular enzyme, pH 7 worked best. When compared to high levels of pH, the lower levels worked better. The wrong level of pH can denature enzymes; therefore finding the right level is essential. The independent variable was the amount of pH, and the dependent being the rate of oxygen. The results are reliable as they are reinforced by the fact that enzymes typically work best at neutral pH

“‘She was competent, decisive, self-reliant; perhaps she intimidated them, for before long they drifted their attentions elsewhere’” (93).

Moreover, CtXynGH30 also displayed activity against the polysaccharides having xylan main chain decorated with arabinose side chains such as arabinoxylans. Therefore a range of substrates showing the enzyme activities were treated with CtXynGH30 and the hydrolysed products were analyzed by TLC. The results showed that the enzyme is active against different polysaccharides and produces a series of oligosaccharides. The enzyme is active on xylan main chain polysaccharide substrates like beechwood-, birchwood- and 4-O-methyl glucurono-xylan and capable of releasing oligosaccharides such as xylose, xylobiose and other higher neutral and acidic oligosaccharides (Lane 1-3, Fig. 5). CtXynGH30 also acted over substrates having xylan main chain decorated with various degrees of arabinose side chains like oat spelt xylan, wheat arabinoxylan and rye arabinoxylan and producing xylobiose, xylotriose and other higher oligosaccharides (Lane 4-6, Fig. 5). Furthermore, the TLC profile of CtXynGH30 showed hydrolysis of arabinogalactan and more likely the release of arabino- oligosaccharides (Lane 7, Fig. 5), whereas, arabinan (sugar beet) and xyloglucan did not release any hydrolysed product (Lane 8-9, Fig. 5). The ability of CtXynGH30 to hydrolyse arabinoxylans apart from glucuronoxylans

Enzymes are very large globular proteins with three dimensional shapes which is vital for enzyme activity as natural catalyst in chemical reactions within the living organisms (7).

The independent variable in this investigation is pH. Each individual enzyme has it’s own pH characteristic. This is because the hydrogen and ionic bonds between –NH2 and –COOH groups of the polypeptides that make up the enzyme, fix the exact arrangement of the active site of an enzyme. It is crucial to be aware of how even small changes in the

J. Moldovan & B. Nilson, (2010), Lab 4 – Enzyme Kinetics, UBCO BIOL/BIOC 393, UBC Vista accessed Monday, November 8th, 2010.

The results recorded in (table 30) and (figure 32) Indicated that Cu+2 activated the enzyme at 0.01M concentration by 1.2 fold and the activity gradually decrease by increasing the metal concentration to 0.1M with activity 51.29U/mg protein. Na+ ion activate the enzyme when added with 0.1M by

“Enzymes are proteins that have catalytic functions” [1], “that speed up or slow down reactions”[2], “indispensable to maintenance and activity of life”[1]. They are each very specific, and will only work when a particular substrate fits in their active site. An active site is “a region on the surface of an enzyme where the substrate binds, and where the reaction occurs”[2].

In the exercise # 2 we observed the effect of substrate concentration, enzyme concentration, pH and temperature on enzyme activity. All the data showed that once potato extract was added to catechol and water the reaction varied dependent on the level of catechol. As in

Enzymes are very specific in nature, which helps them in reactions. When an enzyme recognizes its specific substrate, the

Proteases in the MEROPS protease database have been subdivided into families and clans on the basis of evolutionary relationships (http://merops.sanger.ac.uk) (Rawlings et al., 2014). A protease clan refers to proteases derived from a single common ancestor, and clans are subdivided into families. A protease family refers to a sub-group of proteases that share sequence similarity, either throughout the entire protein sequence or only within the catalytic domain. The Arabidopsis thaliana genome encodes 879 known and putative proteases, corresponding to approximately 3.2% of all Arabidopsis protein-coding genes (The Arabidopsis Information Resource). These proteases are distributed over 60 families that belong to around 30 different clans

Enzymes owe their activity to the precise three-dimensional shape of their molecules. According to the 'lock-and-key' hypothesis, the substrates upon which an enzyme fit into a special slot in the enzyme