Alkaline phosphatase (AP) is an enzyme that can be commonly found in a wide range of organisms, from bacteria to all tissues of human body. It is concentrated in the periplasmic space, which gave rise to the name of periplasmic enzyme. The primary function of AP involves catalyzing nonspecific hydrolysis of phosphomonoester to yield alcohol and phosphate molecules (1). As denoted by its name, AP possesses optimum catalytic activities in alkaline conditions. Escherichia coli (E. coli) functions optimally in pH 8, but it may vary among different organisms. AP indirectly regulates the growth of E. coli. When a vital source of nutrient, phosphorus, is limited in the environment, E. coli as well as other bacteria are able to stimulate AP to produce …show more content…
Thus, it contains two active sites and has metal ions that play a key role in regulating catalytic activities and stabilizing enzyme-substrate complex. The active sites are 30Å apart from each other (7). As proposed by Gettins and Coleman using NMR studies (6), each active site of AP comprises of three metal binding sites, which acknowledged as M1, M2, and M3. Two zinc ions bind to M1 and M2 sites while a magnesium ion occupies M3. In each active site, two zinc ions are 4Å apart while magnesium ion is 5Å and 7Å away from two zinc ions (7). The structures of AP are shown in Figure 1, which specifically indicating metal binding sites and interaction with essential amino acids in active …show more content…
Various methods such as x-ray crystallography, NMR, and site-directed mutagenesis are applied to study how AP structure contributes to its function and how cofactors and amino acid residues affect reaction mechanism. Enzymes that retain similar structure and function to E. coli AP are found in other species and organisms. For instance, the physiological functions of human AP are still not known at present, but the level of alkaline phosphatase in bloodstream can be a valuable indicator to diagnose liver and bone diseases. Also, mutation in structural gene of human AP will result in hypophosphatasia, a metabolic disease that interfere with uptake of phosphorus and calcium. Thus, understanding the functions of metal ions and reaction mechanism of E. coli AP will provide a general insight of how other enzymes work and discover future potential use of AP in different areas of research or clinical
Living organisms undergo chemical reactions with the help of unique proteins known as enzymes. Enzymes significantly assist in these processes by accelerating the rate of reaction in order to maintain life in the organism. Without enzymes, an organism would not be able to survive as long, because its chemical reactions would be too slow to prolong life. The properties and functions of enzymes during chemical reactions can help analyze the activity of the specific enzyme catalase, which can be found in bovine liver and yeast. Our hypothesis regarding enzyme activity is that the aspects of biology and environmental factors contribute to the different enzyme activities between bovine liver and yeast.
Fermentation is the biological process which allows humans to brew beer, or any other alcoholic beverage. This process occurs in the absence of oxygen, as a means for the cell to produce adenosine triphosphate (ATP), the source of cellular energy. Though little energy can be produced in this manner, it allows the yeast to survive in t...
called an active site. This active site is made by a few of the amino
The effect of a change in PH on enzymes is the alteration in the ionic
Peroxidase activity’s optimum pH was found to be pH 5, since the absorbance rate was the highest at 0.3493. Little activity occurred at pH 3, but the absorbance of the reaction with pH 7 rose steadily to 0.99. The rate of absorbance for peroxidase with pH 9 was 0.0097; pH 9 is incapable of accelerating enzyme activity. This suggests that an alkaline pH is inferior to an acidic pH in increasing peroxidase activity, and that the higher the pH level, the poorer the pH boosts the reaction. A highly acidic pH also reduces
The Effect of pH on the Activity of Catalase Planning Experimental Work Secondary Resources Catalase is a type of enzyme found in different types of foods such as potatoes, apples and livers. It speeds up the disintegration of hydrogen peroxide into water because of the molecule of hydrogen peroxide (H2O2) but it remains unchanged at the end of the reaction.
Purpose: The purpose of this lab is to explore the different factors which effect enzyme activity and the rates of reaction, such as particle size and temperature.
Proteins are one of the main building blocks of the body. They are required for the structure, function, and regulation of the body’s tissues and organs. Even smaller units create proteins; these are called amino acids. There are twenty different types of amino acids, and all twenty are configured in many different chains and sequences, producing differing protein structures and functions. An enzyme is a specialized protein that participates in chemical reactions where they serve as catalysts to speed up said reactions, or reduce the energy of activation, noted as Ea (Mader & Windelspecht).
Alkaline Phosphatase (APase) is an important enzyme in pre-diagnostic treatments making it an intensely studied enzyme. In order to fully understand the biochemical properties of enzymes, a kinetic explanation is essential. The kinetic assessment allows for a mechanism on how the enzyme functions. The experiment performed outlines the kinetic assessment for the purification of APase, which was purified in latter experiments through the lysis of E.coli’s bacterial cell wall. This kinetic experiment exploits the catalytic process of APase; APase catalyzes a hydrolysis reaction to produce an inorganic phosphate and alcohol via an intermediate complex.1 Using the Michaelis-Menton model for kinetic characteristics, the kinetic values of APase were found by evaluating the enzymatic rate using a paranitrophenyl phosphate (PNPP) substrate. This model uses an equation to describe enzymatic rates, by relating the
Investigate the Effect of pH on Immobilised Yeast Cells on the Breakdown of Hydrogen Peroxide
Investigating Factors that Affect the Rate of Catalase Action Investigation into the factors which affect the rate of catalase action. Planning Aim: To investigate the affect of concentration of the enzyme catalase on the decomposition reaction of hydrogen peroxide. The enzyme: Catalase is an enzyme found within the cells of many different plants and animals. In this case, it is found in celery.
Many factors, for example, pH and temperature affects the way enzymes work by either increasing the rate or determining the type of product produced (). The report, therefore, analyses the effects of the enzyme peroxidase in metabolic reactions and determining its optimum temperature in the reactions.
The Effect of pH on Enzyme Activity. pH is a measure of the concentration of hydrogen ions in a solution. The higher the hydrogen ion concentration, the lower the pH. Most enzymes function efficiently over a narrow pH range. A change in pH above or below this range reduces the rate of enzyme reaction. considerably.
Enzymes are protein molecules that are made by organisms to catalyze reactions. Typically, enzymes speeds up the rate of the reaction within cells. Enzymes are primarily important to living organisms because it helps with metabolism and the digestive system. For example, enzymes can break larger molecules into smaller molecules to help the body absorb the smaller pieces faster. In addition, some enzyme molecules bind molecules together. However, the initial purpose of the enzyme is to speed up reactions for a certain reason because they are “highly selective catalysts” (Castro J. 2014). In other words, an enzyme is a catalyst, which is a substance that increases the rate of a reaction without undergoing changes. Moreover, enzymes work with
(Khan): further states, here L are the Ligand and which is formed via the complete replacement of water molecules by other ligands can occur till the formation of the MLn complex. “n” is the coordination number of the metal ion and represents the maximum number of monodentate ligands which can be bound to it [8]