The word “enzyme” is derived from the Modern Greek “enzumos,” which directly translates into “leavened.” Enzymes are generally biological molecules that living organisms produce in order to catalyze (which, in this case, to increase the speed or rates of) specific biochemical reactions. The substrates, which are what molecules are called at the beginning of the enzymatic reaction, will be converted into different molecules, known as products. Almost every chemical reaction that occurs in a biological cell will need enzymes in order to perform at a rate that is sufficient for sustaining life.
As with other biological catalysts, enzymes function through the process of lowering the activation energy for a reaction. This process will dramatically increase the rate of the enzymatic reaction and will allow the products (the result of enzymatic reactions) to form faster, and for reactions to achieve their equilibrium states in a shorter amount of time. With the use of enzymes as catalysts, the reactions are a million times faster than those reactions that do not utilize enzymes.
The activity of enzymes can be affected by other molecules. Inhibitors are known to be molecules that decrease the activity of enzymes, while activators are known as molecules that increase the activity of enzymes. Many kinds of drugs and poisons function as enzyme inhibitors. The activity of enzymes can also be affected by pressure, temperature, the chemical environment, and the concentration of a specific substrate.
There are enzymes that are used for commercial purposes, such as in the synthesis of various antibiotics. Some household products use enzymes in order to speed up several biochemical reactions—enzymes are known to be used in biological washing powders that are designed to break down protein and fat stains on clothes.
This category contains scientific information on enzymes, which are biological molecules that living organisms produce in order to catalyze (which, in this case, to increase the speed or rates of) specific biochemical reactions.
Watts K.C., 1987: Preparatory methods for dna hydrolysis cytochemistry immunocytochemistry and ploidy analysis their application to automated and routine diagnostic cytopathology. Analytical & Quantitative Cytology & Histology: 218-224 A review is presented of some methods used to prepare cytologic specimens for analytical and/or automated studies, with the steps of the procedures detailed in appendices. The [...]
Saito K., 1985: Preparative studies on the isolation of an enzyme associated with carthamin synthesis in carthamus tinctorius. Acta Societatis Botanicorum Poloniae: 403-416 Preliminary operations for the isolation of an enzyme associated with cathamin synthesis (carthamin-synthesizing enzyme) were done with a soluble extract of safflower seedlings. Ethanol and acetone seriously affected the solubility and the [...]
Klibanov A.M., 1983: Preparative separation of alpha naphthols and beta naphthols catalyzed by immobilized sulfatase. Biotechnology & Bioengineering: 919-928 Sulfatase from Helix pomatia hydrolyzes.beta.-naphthyl sulfate much faster than.alpha.-naphthyl sulfate; e.g., at pH 7.8, while the former is readily hydrolyzed, the latter undergoes no appreciable hydrolysis. Kinetic investigations of both enzymatic and acid hydrolysis of naphthyl [...]
Carrea G., 1986: Preparative scale regiospecific and stereospecific oxidoreduction of cholic acid and dehydrocholic acid catalyzed by hydroxysteroid dehydrogenases. Journal Of Organic Chemistry: 2902-2906 Nad(P)-dependent hydroxysteroid dehydrogenases were used as catalysts for the oxidoreduction of the hydroxyl-keto groups of cholic acid (3.alpha.,7.alpha.,12.alpha.-trihydroxy-5.beta.-cholan-24-oic acid) and dehydrocholic acid (3,7,12-trioxo-5.beta.-cholan-24-oic acid). Cholic acid was regiospecifically oxidized, on a [...]
Klibanov A.M., 1985: Preparative resolution of d l threonine catalyzed by immobilized phosphatase. Biotechnology & Bioengineering: 247-252 Hydrolysis of L- and D-O-phosphothreonines catalyzed by 4 different phosphatases, alkaline phosphatases from calf intestine and Escherichia coli and acid phosphatases from wheat germ and potato, was kinetically studied. Alkaline phosphatases have comparable reactivities towards the optical isomers. [...]
Klibanov A.M., 1984: Preparative production of optically active esters and alcohols using esterase catalyzed stereospecific trans esterification in organic media. Journal Of The American Chemical Society: 2687-2692 A novel enzymatic approach to the production of optically active alcohols and esters from racemates is developed. It involves the use of esterase catalyzed transesterifications carried out in [...]
Battersby, R.; Holloway, C. J., 1982: Preparative isotachophoresis in a flat bed of granulated gel principles and procedures comparison with iso electric focusing and application to the isolation of a low iso electric point high mobility form of cat liver cytosolic glutathione s transferase ec 22.214.171.124. Electrophoresis 3(5): 275-284 A method is reported for the [...]
Ivanishchev V.V., 1988: Preparative isolation of phosphoribulokinase. Prikladnaya Biokhimiya I Mikrobiologiya: 125-128 A technique for preparative isolation of electrophoretically homogeneous phosphoribulokinase from bean leaves is described. The isolated enzyme has a molecular weight of about 250,000. It is a tetramer composed of subunits with amolecular weight of about 60,000. The enzyme is characterized by the [...]
Wu D., 1985: Preparative isolation of peroxisomes from liver and kidney using metrizamide density gradient centrifugation in a vertical rotor. Analytical Biochemistry: 233-244 A method for the preparative isolation of peroxisomes from the livers of rat, guinea pig, and mouse, and also from rat kidney is described. The light mitochondrial fraction, i.e., particles sedimenting between [...]
Rakhimov A.Kh, 1987: Preparative isolation of lipases from the fungus rhizopus microsporus. Biotekhnologiya: 26 A procedure for simultaneous quantitative isolation of all of the existing lipases from Rhizopus microsporus fungus was developed. Five forms of lipases with different molecular masses were isolated. Some properties of the isolated lipases, such as pH-optimum, thermostability, specific activity and [...]