8/13/2019 TANAY 2038 Biotech Assignment1

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IN 309: Building Biotechnology: Science, Business, Law and Ethics

Assignment 1: Date: 20/ 01/2014 Submitted By: Tanay Patel (10002038)

Name of protein: Lysozyme

Introduction:

Lysozyme is the enzymes which plays important role in protecting us from the bacterial infection. It attacks on t

protective cell wall of the bacteria which is made of with carbohydrate and peptide chains. Lysozyme breaks thcarbohydrate chains and destroy the construction of the cell wall. After that, bacteria burst because of their owinternal osmotic pressure. Due to its antibacterial effects, it is an important member of the immune system.

Lysozyme found in tears, saliva, kidney tissue, cervical mucus, blood, milk, egg white,and other areas that asusceptible to potential bacteria growth.

Apart from antibacterial characteristics, it is also responsible for the initial digestion of starches in mouth. Heggs white is the main sources of lysozyme for commercial supplies.

Lysozyme was first officially characterized and noticed by the Alexander Fleming. It cannot be useful as dru

because it has large size so it is difficult to travel between the cells. Fleming continued his research and five yealater he found true antibiotic drug: penicillin.

Size and Characteristics:

Lysozyme occupies an ellipsoidal shape with dimensions of roughly 45 x 30 x 30 and possesses a complex foldistructure. The primary structure of lysozyme is single polypeptide which contains 129 amino acids. It consists alpha () helixes and contains a -sheet structure in various areas along the polypeptide chain. Visually lysozymis the White, lyophilized powder. It has pH level approx. 4.5 to 4.9.

What does it do.?

Lysozyme is known for damaging bacterial cell walls by catalyzing the hydrolysis of 1,4-beta-linkages between Nacetylmuramic acid (NAM) and N-acetyl-D-glucosamine (NAG) residues in peptidoglycan, and between N-acetyl-glucosamine residues in chitodextrins. By breaking the 1,4 glycosidic bonds that link the sugars of thepolysaccharides, the structural integrity of the bacterial cell wall is compromised and the bacterium bursts undthe high internal osmotic pressure. Because it is commonly found in the places where microorganisms are molikely to enter the body, lysozyme is one of the powerful first line defenses against bacterial infection.

Structure and Mechanism

Lysozyme mainly has carbon, oxygen, nitrogen and sulfur atoms. It has amino acids residues. Like all othproteins it also contains 3C and 5N terminal.Lysozyme protein has two major domains (alpha and beta), and

has one active site as shown in figure. The alpha domain of the molecule is build up primarily of alpha helic(magenta), while the beta domain contains the only beta sheets (gold) and few helices. The active site is locatedeep within the cleft between the two domains. The deep gap between the two domains forms a cradle in whicthe long polysaccharides are confined.

First enzymes (lysozyme) and substrate (polysaccharide) associate and creates the enzyme substrate compleEnzymes catalyzed the hydrolysis reaction and it cleaves the substrate in to product which are quickly release anallowing the enzyme to catalyzed the another reaction.

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The cleft in the enzymes hold six sugar residues of a polysaccharide. The hydrolysis reaction occurs between theresidues. Sugar residues have their most stable 3D configuration. However after the polysaccharide enter tenzymes-substrate complex, the enzymes forces the sugar into the strange configuratio

Figure 1: Enzyme structure with substrate

There are two amino acid within the enzymfacilitate the reaction. Glu 35 and Asp 52. Glu donates the proton to the sugar on the right. Asp 5

attacks on the C1 carbon atoms of the sugar on tleft. This attacks on the C1 carbon results in ttransient covalent bond between sugar and tamino acids and hydrolysis of the sugar-sugar bonThe deprotoned Glu 35 polarized the water molecuand trying to get proton which is lost. This allows thwater oxygen to attacks the C1 carbon and breathe C1 Asp 52 bond. In this way two amino acreturns in to their original states and forming tenzymes products complex. After that the enzym

and products dissociate.

Application of Lysozyme:

Since lysozyme has been well known for its antibacterial and antifungal characteristics, it has wide verity

application in biochemical, pharmaceutical industries and food processing industries. In molecular biolog

lysozyme is often used in the alkaline-lysis procedure for extracting and isolating plasmid DNA. It is use

extensively in the pharmaceutical field for destroying gram-positive bacteria. Lysozyme can be also used f

preventing the food (like dairy products) from spoilage in food industries.

References:

http://www.rcsb.org/pdb/101/motm_archive.do

https://www.youtube.com/watch?v=YNSq8fv3rQk

http://www.bmrb.wisc.edu/featuredSys/Lysozyme/lysozyme1.html

http://link.springer.com/chapter/10.1007%2F978-0-387-36534-3_14#page-1

http://www.sb.fsu.edu/~soma/Proj/YSP/08YSP/2008_IRP-Paper.pdf

http://maptest.rutgers.edu/drupal/?q=node/51

http://www.rcsb.org/pdb/101/motm_archive.dohttp://www.rcsb.org/pdb/101/motm_archive.dohttp://www.bmrb.wisc.edu/featuredSys/Lysozyme/lysozyme1.htmlhttp://www.bmrb.wisc.edu/featuredSys/Lysozyme/lysozyme1.htmlhttp://link.springer.com/chapter/10.1007%2F978-0-387-36534-3_14#page-1http://link.springer.com/chapter/10.1007%2F978-0-387-36534-3_14#page-1http://www.sb.fsu.edu/~soma/Proj/YSP/08YSP/2008_IRP-Paper.pdfhttp://www.sb.fsu.edu/~soma/Proj/YSP/08YSP/2008_IRP-Paper.pdfhttp://maptest.rutgers.edu/drupal/?q=node/51http://maptest.rutgers.edu/drupal/?q=node/51http://maptest.rutgers.edu/drupal/?q=node/51http://www.sb.fsu.edu/~soma/Proj/YSP/08YSP/2008_IRP-Paper.pdfhttp://link.springer.com/chapter/10.1007%2F978-0-387-36534-3_14#page-1http://www.bmrb.wisc.edu/featuredSys/Lysozyme/lysozyme1.htmlhttp://www.rcsb.org/pdb/101/motm_archive.do