Source of Glucose Isomerase
Entropy is a measure of the number of specific ways in which a system may be arranged, often taken to be a measure of disorder, or a measure of progressing towards thermodynamic equilibrium. The entropy of an isolated system never decreases, because isolated systems spontaneously evolve towards thermodynamic equilibrium, which is the state of maximum entropy.
As an example, for a glass of ice water in air at room temperature, the difference in temperature between a warm room (the surroundings) and cold glass of ice and water (the system and not part of the room), begins to be equalized as portions of the thermal energy from the warm surroundings spread to the cooler system of ice and water. Over time the temperature of the glass and its contents and the temperature of the room become equal. The entropy of the room has decreased as some of its energy has been dispersed to the ice and water. However, as calculated in the example, the entropy of the system of ice and water has increased more than the entropy of the surrounding room has decreased. In an isolated system such as the room and ice water taken together, the dispersal of energy from warmer to cooler always results in a net increase in entropy. Thus, when the "universe" of the room and ice water system has reached a temperature equilibrium, the entropy change from the initial state is at a maximum. The entropy of the thermodynamic system is a measure of how far the equalization has progressed
Source of glucose isomerase A process for the production of glucose isomerase, comprising cultivating under aerobic conditions an atypical Bacillus coagulans productive of a glucose isomerase, said Bacillus coagulans being capable of growth on only inorganic nitrogen sources as the nitrogen source and at a temperature of 65 source, a carbon source, optionally including xylose, small amounts of inorganic salts, at a pH value between 5 and 9 and a temperature between 40 is recovered. Enzymes capable of isomerizing glucose to fructose may be obtained from a large number of different microorganism species, and the properties of the enzymes vary from species to species. Enzyme properties, which are particularly important for the use in the isomerization process are, stability at high temperatures and activity at low pH values. In an enzymatic isomerization of glucose to fructose, the following conditions are of importance:
PH: A pH value as low as possible is desired in order to avoid the alkali-catalyzed by-product formation, i.e. below pH 7, pH 5-7 is a suitable range. Temperature: The enzyme should be stable at a temperature of about 55
A urine test strip or dipstick is a basic diagnostic tool used to determine pathological changes in a patient’s urine in standard urinalysis. Active Site of An Enzyme In biology, the active site is the small portion of an enzyme where substrate molecules bind and undergo a chemical reaction. This chemical reaction occurs when a substrate collides with and slots into the active site of an enzyme. The active site is usually found in a 3-D groove or pocket of the enzyme, lined with amino acid residues (or nucleotides in RNA enzymes). These residues are involved in recognition of the substrate. Residues that directly participate in the catalytic reaction mechanism are called active site residues. After an active site has been involved in a reaction, it can be used again.
An active site is the part of an enzyme that directly binds to a substrate and carries a reaction. It contains catalytic groups which are amino acids that promote formation and degradation of bonds. By forming and breaking these bonds, enzyme and substrate interaction promotes the formation of the transition state structure. Enzymes help a reaction by stabilizing the transition state intermediate. This is accomplished by lowering the energy barrier or activation energythe energy that is required to promote the formation of transition state intermediate. The three dimensional cleft is formed by the groups that come from different part of the amino acid sequences. The active site is only a small part of the total enzyme volume. It enhances the enzyme to bind to substrate and catalysis by many different weak interactions because of its nonpolar microenvironment. The weak interactions includes the Van der Waals, hydrogen bonding, and electrostatic interactions. The arrangement of atoms in the active site is crucial for binding spectificity. The overall result is the acceleration of the reaction process and increasing the rate of reaction. Furthermore, not only do enzymes contain catalytic abilities, but the active site also carries the recognition of substrate. The enzyme active site is the binding site for catalytic and inhibition reactions of enzyme and substrate; structure of active site and its chemical characteristic are of specific for the binding of a particular substrate. The binding of the substrate to the enzyme causes changes in the chemical bonds of the substrate and causes the reactions that lead to the formation of products. The products are released from the enzyme surface to regenerate the enzyme for another reaction cycle The active site is in the shape of a three-dimensional cleft that is composed of amino acids from different residues of the primary amino acid sequence. The amino acids that play a significant role in the binding specificity of the active site are usually not adjacent to each other in the primary structure, but form the active site as a result of folding in creating the tertiary structure. This active site region is relatively small compared to the rest of the enzyme. Similar to
a ligand-binding site, the majority of an enzyme (non-binding amino acid residues) exist primarily to serve as a framework to support the structure of the active site by providing correct orientation. The unique amino acids contained in an active site promote specific interactions that are necessary for proper binding and resulting catalysis. Enzyme specificity depends on the arrangement of atoms in the active site. Complementary shapes between enzyme and substrate(s) allow a greater amount of weak non-covalent interactions including electrostatic forces, Van der Waals forces, hydrogen bonding, and hydrophobic interactions. Specific amino acids also allow the formation of hydrogen bonds. That shows the uniqueness of the microenvironment for the active site. To locate the active site, the enzyme of interest is crystallized in the presence of an analog. The analog’s resemblance of the original substrate would be considered a potent competitive inhibitor that blocks the original substrates from binding to the active sites. One can then locate the active sites on an enzyme by following where the analog binds.