Lactic acid production
Acetate oxidation through a modified citric acid cycle in Propionibacterium freudenreichiiRobert Horton, Laurence A. Gray Scrimeour, Marc D. David Rawn, Pearson Studium, München. Webmaster06 Aug Most important for… Prospective Students Students.
A Broader View: Microbial Enzymes and Their Relevance in Industries, Medicine, and Beyond
Enzymes are the large biomolecules that are required for the numerous chemical interconversions that sustain life. They accelerate all the metabolic processes in the body and carry out a specific task. Enzymes are highly efficient, which can increase reaction rates by million to 10 billion times faster than any normal chemical reaction.
Due to development in recombinant technology and protein engineering, enzymes have evolved as an important molecule that has been widely used in different industrial and therapeutical purposes.
Microbial enzymes are currently acquiring much attention with rapid development of enzyme technology. Microbial enzymes are preferred due to their economic feasibility, high yields, consistency, ease of product modification and optimization, regular supply due to absence of seasonal fluctuations, rapid growth of microbes on inexpensive media, stability, and greater catalytic activity.
Microbial enzymes play a major role in the diagnosis, treatment, biochemical investigation, and monitoring of various dreaded diseases. Amylase and lipase are two very important enzymes that have been vastly studied and have great importance in different industries and therapeutic industry.
In this review, an approach has been made to highlight the importance of different enzymes with special emphasis on amylase and lipase in the different industrial and medical fields.
Enzymes are the biological substance or biological macromolecules that are produced by a living organism which acts as a catalyst to bring about a specific biochemical reaction.
Even many centuries ago enzyme and its use were well known to the mankind but Wilhelm Friedrich Kühne was the first person to give a scientific terminology to this biomolecule. Use of enzyme has been seen in ancient Egyptians where they were used for the preservation of food and beverages. Cheese making has always involved the use of enzymes, and it goes as far as back in about BC, when Homer's Iliad mentioned the use of a kid's stomach for making cheese.
In , the famous Italian catholic priest Lazzaro Spallanzani first mentioned the importance of this biomolecule in his work of biogenesis spontaneous generation of microbes where he mentioned that there is a life-generating force inherent to certain kinds of inorganic matter that causes living microbes to create themselves given sufficient time [ 2 ]. In the year Gottlieb Sigismund Kirchhoff was investigating the procedure of converting starch into glucose.
In his experiment he also enlightens the application of these biomolecules as catalyst [ 3 ]. In , French chemist Anselme Payen discovered the first enzyme, diastase [ 4 ]. In , the hydrolysis of starch by diastase was acknowledged as a catalytic reaction by another Swedish scientist Jöns Jacob Berzelius. In , he also interpreted fermentation as being caused by a catalytic force and postulated that a body—by its mere presence—could, by affinity to the fermentable substance, cause its rearrangement to the products [ 5 ].
In the activity of invertase was demonstrated by Dubonfout. In , Jokichi Takamine discovered takadiastase which is the form of diastase obtained from Aspergillus oryzae. In , Eduard Buchner demonstrated the conversion of glucose to ethanol by a cell-free extract from the yeast. Later in , Otto Rohm, German scientist, introduced application of pancreatic enzymes with inorganic salts to meet the requirement in tanneries for bating of hides.
Griffin showed the adsorption of invertase on charcoal and alumina demonstrating that immobilised enzymes can be retained. At present, immobilized cells have been used for production of organic acids, amino acids, antibiotics, enzymes, alcohol, and other compounds. Immobilized cell techniques have several advantages as compared to the free cell system, such as higher production rate and easier product separation [ 7 ].
It was not until , however, that the first enzyme was obtained in pure form, a feat accomplished by James B. Sumner of Cornell University. Sumner in was able to isolate and crystallize the enzyme urease from the jack bean.
His work was to earn him the Nobel Prize. Northrop and Wendell M. Stanley shared the Nobel Prize with Sumner.
They discovered a complex procedure for isolating pepsin. This precipitation technique devised by Northrop and Stanley has been used to crystallize several enzymes [ 8 ]. After , many scientists started application of genetic engineering techniques in order to improve the production of enzymes and also to alter the properties of enzymes by protein engineering. Naturally found enzymes have been used widely since ancient times and in the manufacture of products such as linen, leather, and indigo.
All of these processes dependent on either enzymes produced by microorganisms or enzymes present in added preparations such as calves' rumen or papaya fruit. The development of fermentation processes was aimed specifically at the production of enzymes by use of particularly selected strains, due to which it is possible to produce purified, well-characterized enzymes on a large scale. This development allowed the introduction of enzymes into true industrial products and processes, for example, within the detergent, textile, and starch industries.
The recombinant DNA technology has further improved production processes and helped to produce enzymes commercially that could not be produced previously. Furthermore, the developments in biotechnology, such as protein engineering and directed evolution, further revolutionized the commercialization of industrial important enzymes. This advance in biotechnology is providing different kinds of enzymes displaying new activities, adaptability to new conditions leading to their increase use in industrial purposes.
Since s, the intensive research biochemistry confronted the use of enzymes as diagnostic tool and also provided basis in clinical chemistry. It is, however, only within the recent past few decades that interest in diagnostic enzymology has multiplied. Many methods currently on record in the literature are not in wide use, and there are still large areas of medical research in which the diagnostic potential of enzyme reactions has not been explored at all.
The majority of currently used industrial enzymes are hydrolytic in action, being used for the degradation of various natural substances.
Proteases remain the dominant enzyme type, because of their extensive use in the detergent and dairy industries. Various carbohydrases, primarily amylases and cellulases, used in industries such as the starch, textile, detergent, and baking industries, represent the second largest group [ 9 ].
The global market for industrial enzymes is estimated at 3. This market is expected to reach more than 4 billion dollars by Enzymes play key roles in numerous biotechnology products and processes that are commonly encountered in the production of food and beverages, cleaning supplies, clothing, paper products, transportation fuels, pharmaceuticals, and monitoring devices. At present, the most frequently used enzymes in biotechnology are hydrolases, which catalyse the breakdown of molecules.
Enzymes can display regional stereospecificity, properties that have been exploited for asymmetric synthesis and racemic resolution.
Chiral selectivity of enzymes has been employed to prepare enantiomerically pure pharmaceuticals, agrochemicals, chemical feedstock, and food additives. Thus, enzymes do show us a wide range of applications in different industries whether it may be food, textile, medicine, dairy, or any other.
With the advancement of modern biotechnology and protein engineering we have the capability to introduce or modify the capability of the genes that are important for us to produce these novel enzymes. Our objective in writing this review is to emphasize the current role of the microbial enzymes and the current status of their use in different industries along with the biotechnological perspectives of its future development.
Enzymes are large biological molecules responsible for all those important chemical interconversions that are required to sustain life [ 10 ]. They are highly selective catalysts which can greatly accelerate both the rate and specificity of metabolic reactions, which range from the digestion of food to the synthesis of DNA.
Almost all chemical reactions in a biological cell need enzymes in order to occur at rates sufficient for life. Since enzymes are selective for their substrates and speed up only a few reactions from among many possibilities, the set of enzymes made in a cell determines which metabolic pathways occur in that cell. Enzymes are known to catalyse about 4, biochemical reactions [ 11 ]. Enzymes are very specific, and it was suggested by the Nobel laureate Emil Fischer in that this was because both the enzyme and the substrate possess specific complementary geometric shapes that fit exactly into one another [ 12 ].
However, while this model explains enzyme specificity, it fails to explain the stabilization of the transition state that enzymes achieve. Most enzymes are much larger than the substrates they act on, and only a small portion of the enzyme around 2—4 amino acids is directly involved in catalysis [ 13 ]. The region that contains these catalytic residues, binds the substrate, and then carries out the reaction is known as the active site.
Enzymes can also contain sites that bind cofactors, which are needed for catalysis. Some enzymes also have binding sites for small molecules, which are often direct or indirect products or substrates of the reaction catalyzed. This binding can serve to increase or decrease the enzyme's activity, providing a means for feedback regulation. Like all proteins, enzymes are long, linear chains of amino acids that fold to produce a three-dimensional product. Each unique amino acid sequence produces a specific structure, which has unique properties.
Individual protein chains may sometimes group together to form a protein complex. Most enzymes can be denatured that is, unfolded and inactivated by heating or chemical denaturants, which disrupt the three-dimensional structure of the protein. Depending on the enzyme, denaturation may be reversible or irreversible.
Due to their wide range of activities based on their nature of reaction enzymes are being classified according to their enzyme catalysing reaction as shown in Table 1. The Enzyme Commission number EC number is a numerical classification scheme for enzymes, based on the chemical reactions they catalyze [ 14 ]. As a system of enzyme nomenclature, every EC number is associated with a recommended name for the respective enzyme. The first version was published in The current sixth edition, published by the International Union of Biochemistry and Molecular Biology in , contains different enzymes.
The International Union of Biochemistry I. According to the enzyme commission the enzymes are divide into 6 parts:. Enzyme classes and types of reactions [ 14 ]. In Table 2 examples of few classes of industrially important enzymes are given. Amylase is an enzyme that catalyses the breakdown of starch into sugars. Amylase is abundantly present in human saliva as shown in Figure 1 , where it begins the mechanical process of digestion. Foods that contain much starch but little sugar, such as rice and potato, taste slightly sweet as they are chewed because amylase turns some of their starch into sugar in the mouth.
The pancreas also makes amylase alpha amylase to hydrolyse dietary starch into disaccharides and trisaccharides which are converted by other enzymes to glucose to supply the body with energy.
Plants and some bacteria also produce amylase. As diastase, amylase was the first enzyme to be discovered and isolated by Anselme Payen in Today amylase has almost replaced chemical hydrolysis of starch in starch processing industry. The amylases obtained from microorganisms have a broad spectrum of industrial uses as they are more stable than plant and animal amylases. The major advantage of using microorganisms for the production of amylases is the economical bulk production capacity, and also microbes are easy to manipulate to derive enzymes of desired nature.
Starch-degrading amylolytic enzymes are of great importance in biotechnological sector ranging from food, fermentation, textile to paper industries [ 17 , 18 ]. Although amylases can be obtained from several sources, like plants and animals, the enzymes from microbial sources generally satisfy industrial demands and had made significant contribution to the foods and beverages industry in the last three decades.
Computer simulated 3D image of human salivary amylase [ 22 ]. The classification is based on the bonding type. It is the major form of amylase found in humans and other mammals [ 21 ].
It is also present in seeds containing starch as a food reserve and is secreted by many fungi. In humans, all amylase isoforms link to chromosome 1p21 AMY1A.
Materials and Methods
A Broader View: Microbial Enzymes and Their Relevance in Industries, Medicine, and Beyond
Beauprez JJ, De Mey M, Soetaert WK () Microbial succinic acid () Batch and continuous culture ofLactococcus lactisNZ experimental data and model – Kubicek CP, Karaffa L () Citric Acid Pro- cesses. Succinic acid production from microbial organisms has tremendous potential For detailed marketing data and information, the reader is referred to one of the SRI This inhibition ensures that all of the PEP in the reaction is fed into the citric. 11 Sep Microbial enzymes play a major role in the diagnosis, treatment, (IISER-K) for providing all the necessary facilities to gather relevant data for this topic. Wang JL, Liu P. Comparison of citric acid production by Aspergillus.