Lastly there is the quaternary structure, this structure is found in proteins containing more than one polypeptide chain, and simply means how the different polypeptide chains are arranged together. The individual polypeptide chains are usually globular, but can arrange themselves into a variety of quaternary shapes.
I am now going to look at the uses of enzymes in industry. Firstly I will be exploring the use of enzymes in textile industries. They are used because they accelerate reactions, act only on specific substrates, operate under mild conditions, are safe and easy to control, can replace harsh chemicals and are biodegradable. In the textiles industry enzymes are used during the finishing of fabric and clothes. Cellulose is the main component of cotton as well as other natural fibres. Although most of the fibres are long some of the smaller fibres can obtrude from the fabric, these can be removed using the cellulase in a process called biopolishing. The result is a smoother, glossy fabric. Another use of enzymes in the textile industry is in a process called biostoning; during this process cellulase is put on the jeans to create a stonewashed effect without as much damage being caused to the garment compared to using pumice stones which were used originally.
Another industry that regularly uses enzymes is the bread baking industry. The main component of bread is wheat flour which has naturally occurring enzymes that change the starch, fibre and protein in the flour when water is added. The yeast also has enzymes that make the bread rise by fermenting and producing carbon dioxide. Enzymes are used as supplements in the bread making process to make the process more proficient. The enzymes used are xylanase, α-amylase, protease, glucose oxidase and lipase which are activated when water is added to make the dough. These make the dough easier to handle and control taste, volume and texture. Enzymes used in baking usually need to be thermo-labile which means that they denature while they are being baked. The enzyme glucose oxidase oxides sulphydryl groups to make dough more flexible and stronger. The reaction between enzymes and parts of the bread dough is very complex and the wrong mixture of cocktails can mean unfavourable effects on the dough and bread. If too much enzyme was put in the dough the bread may not rise properly.
Enzymes have also been used in the detergent industry for over 40 years, particularly in laundry products such as biological washing powder, liquid and tablets. Protease is the main enzyme used in detergents and removes stains such as grass, blood, egg and human sweat, although recently other enzymes such as lipase and amylase are used as well. Lipases break down fats and oils and amylases help remove starchy stains. Colour enhancing washing powders have now been produced containing celluloses which remove cellulose fibrils that dull the colour of the fabric due to the dirt trapped on the surface. Synthetic enzymes greatly increased the cleaning efficiency of common household detergents by accelerating the hydrolysis of animal fats (such as glycerides) and oily food residues (including proteins) so that they could be more rapidly dispersed and emulsified in water. Detergent enzymes are well established as normal ingredients in both powder and liquid detergents all over the world. The enzymatic hydrolysis of tri-glycerides in alkaline solutions is used as a measure of detergent efficiency. Many synthetic enzymes are derived from quaternary ammonium compounds.
Further industries that use enzymes include the brewing industry. This uses enzymes such as amylases, glucanases and proteases which are added to unmalted barley and produce the same simple sugars and amino acids as malting only more easily. Enzymes are also used to improve filtration. Filtration rates are increased and fouling of filtration membranes is prevented by adding xylanases or glucanases which break down polysaccharides that slow the filtration down.
Enzymes are used in medicine in many different ways. An initial step in detecting liver damage is a simple blood test to determine the presence of certain liver enzymes in the blood. Under normal circumstances, these enzymes reside within the cells of the liver. But when the liver is injured, these enzymes are spilled into the blood stream. Among the most sensitive and widely used of these liver enzymes are the aminotransferases. They include aspartate aminotransferase and alanine aminotransferase (ALT or SGPT). These enzymes are normally contained within liver cells. If the liver is injured, the liver cells spill the enzymes into blood, raising the enzyme levels in the blood and signalling the liver damage.
It is said that enzyme supplements can be helpful--if you have one of the rare conditions that cause enzyme deficiency such as cystic fibrosis, Gaucher's disease, and celiac disease are the leading culprits. Certain enzymes can also help people with specific digestive problems such as lactose intolerance, bloating, and gas. For genuine cases of enzyme deficiency, confirmed by blood tests and assessment of digestive status, doctors prescribe supplements such as Donnazyme, Cotazyme, Creon, Pancrease, Ultrase, and Zymase. For people with lactose intolerance, there's the over-the-counter remedy Lactaid. And for those troubled by chronic gas, there's a product called Beano. Enzyme supplements seek to maintain peak digestion by strengthening the body's natural enzymes with ample supplements from other sources. This is thought to reduce the body's workload, allowing the immune system to flourish and ridding the system of toxic, only partially digested nutrients.
The life of a cell is dependent on the many enzymes that float in the cell's cytoplasm. Many different poisons work by disrupting the balance of the enzymes in one way or another. For example, diphtheria toxin works by gumming up the action of a cell's ribosomes, making it impossible for the ribosome to move along the mRNA strand. The toxin in a death-cap mushroom, on the other hand, gums up the action of RNA polymerase and stops the transcription of DNA. In both cases, the production of new enzymes shuts down and the cells affected by the toxin can no longer grow or reproduce. An antibiotic is a poison that works to destroy bacterial cells while leaving human cells unharmed. All antibiotics take advantage of the fact that there are many differences between the enzymes inside a human cell and the enzymes inside a bacterium. If a toxin is found, for example, that affects an E. coli ribosome but leaves human ribosomes unharmed, then it may be an effective antibiotic. Streptomycin is an example of an antibiotic that works in this way. Penicillin was one of the first antibiotics. It gums up a bacterium's ability to build cell walls. Since bacterial cell walls and human cell walls are very different, penicillin has a big effect on certain species of bacteria but no effect on human cells. The sulfa drugs work by disabling an enzyme that manages the creation of nucleotides in bacteria but not in humans. Without nucleotides, the bacteria cannot reproduce. Below is a diagram of how enzymes are created.
Proteases are used in both wound therapy and as anti-inflammatory reagents. In wound therapy there are used to quicken the healing process by cleaning the wound, they are known as debriding agents. Anti-inflammatory enzymes may help prevent many injuries that would otherwise be unavoidable. Also, if you already have an injury, supplementing enzymes in high doses will break down inflammation by rapidly hydrolysing the waste products which collect around the injured tissue, preventing scar tissue from forming, and speeding your recovery.
In the encyclopaedia an enzyme is described as a protein that catalyses a specific reaction. There are many different uses for enzymes in both industry and medicine, most of which I have explored in this essay. Enzymes are often used in industry and medicine to make processes more efficient, to get better quality results and as a natural remedy for many medical problems. As well as curing medical problems, using enzymes can also help you find the problems in the first place. The diagnosis of certain disorders can be helped by measuring the concentrations of various enzymes in the blood. After a heart attack raised levels of heart enzymes occur as a result of damage to the cells of the heart muscle. Some inherited diseases such as and are the result of deficiencies of certain enzymes.
Bibliography
- http://health.yahoo.com/health/alternative_medicine/alternative_therapies/Enzyme_Therapy/
- The New Illustrated Everyman’s Encyclopedia
- The Dictionary of Science
- New Scientist Journal
