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Semester 4: BIOCHEMISTRY AND APPLIED BIOTECHNOLOGY
Enzyme structure and function
Enzyme structure and function
Basic Structure of Enzymes
Enzymes are proteins that act as catalysts in biochemical reactions. They consist of amino acids arranged in specific sequences that form a unique three-dimensional structure. The active site of an enzyme is where substrate molecules bind and react.
Types of Enzymes
Enzymes can be classified into various categories based on their function, such as hydrolases (catalyzing hydrolysis reactions), oxidoreductases (involved in oxidation-reduction), and ligases (joining two molecules). Each type performs a specific role in metabolic pathways.
Enzyme Mechanism of Action
Enzymes lower the activation energy of reactions, allowing them to proceed more quickly. The lock-and-key model explains how substrates fit into enzymes, while the induced fit model suggests that enzymes can change shape to better fit the substrate upon binding.
Factors Affecting Enzyme Activity
Enzyme activity can be influenced by various factors including temperature, pH, and substrate concentration. Each enzyme has an optimal temperature and pH range for maximum activity.
Enzyme Inhibition
Enzymes can be inhibited by molecules that reduce their activity. Competitive inhibition occurs when an inhibitor competes with the substrate for the active site, while non-competitive inhibition happens when the inhibitor binds to another part of the enzyme.
Applications of Enzymes in Biotechnology
Enzymes are widely used in various biotechnological applications such as food processing, pharmaceuticals, and biofuels. They play a crucial role in enhancing efficiency and sustainability in industrial processes.
Carbohydrate, lipid, and protein metabolism
Carbohydrate, lipid, and protein metabolism
Overview of Metabolism
Metabolism refers to all biochemical processes that occur within living organisms. It encompasses catabolic pathways that break down molecules to produce energy and anabolic pathways that synthesize compounds needed by the cell.
Carbohydrate Metabolism
Carbohydrate metabolism involves the processes through which glucose and other sugars are converted into energy. Key pathways include glycolysis, the citric acid cycle, and oxidative phosphorylation. Glycolysis breaks down glucose into pyruvate, producing ATP and NADH. The citric acid cycle further oxidizes pyruvate, generating GTP, NADH, and FADH2, which feed into the electron transport chain for ATP production.
Lipid Metabolism
Lipid metabolism includes the breakdown and synthesis of fatty acids and triglycerides. Key processes include lipolysis, the breakdown of fats into glycerol and free fatty acids, and beta-oxidation, the catabolic process that converts fatty acids into acetyl-CoA for energy production. Lipid metabolism also involves the synthesis of phospholipids and cholesterol, which are crucial for cell membrane structure.
Protein Metabolism
Protein metabolism encompasses the synthesis and degradation of proteins. Amino acids from dietary proteins undergo deamination to remove amino groups, allowing them to enter metabolic pathways for energy production or for the synthesis of new proteins. The urea cycle helps eliminate excess nitrogen from the body. Key processes include transcription and translation for protein synthesis.
Interconnection of Metabolic Pathways
Carbohydrate, lipid, and protein metabolism are interconnected and influence each other. For instance, excess carbohydrates can be converted into fatty acids through lipogenesis, while intermediates from lipid and protein metabolism can enter glycolytic or citric acid pathways, demonstrating the integrated nature of metabolism in providing energy and building blocks for cellular functions.
Applied biotechnology methods
Biochemistry and Applied Biotechnology
Introduction to Biochemistry
Biochemistry is the study of chemical processes within and relating to living organisms. It combines principles of chemistry and biology to understand how biological molecules give rise to the processes that occur inside living cells.
Biotechnology Methods
Applied biotechnology encompasses a wide range of techniques that utilize biological systems or living organisms to develop or create different products. These methods include genetic engineering, fermentation technology, tissue culture, and molecular markers.
Genetic Engineering
Genetic engineering involves the direct manipulation of an organism's DNA to alter its characteristics. Techniques include CRISPR, recombinant DNA technology, and gene cloning. It has applications in agriculture, medicine, and industry.
Fermentation Technology
Fermentation technology is used in the production of various products such as alcohol, antibiotics, and enzymes. It relies on the metabolic activity of microorganisms, primarily yeast and bacteria, to convert substrates into desired products.
Plant Tissue Culture
Plant tissue culture is a method used to propagate plants under sterile conditions. This technique allows for the production of clones from a single parent plant, facilitating the rapid multiplication of plants and the conservation of endangered species.
Molecular Markers in Biotechnology
Molecular markers are DNA sequences that can be used to identify specific genes or traits in organisms. They play a crucial role in plant breeding, genetic diversity studies, and conservation genetics.
Applications of Applied Biotechnology
The applications of applied biotechnology are vast, including the development of genetically modified organisms (GMOs), production of pharmaceuticals, bioremediation, and biofuels. These innovations aim to improve agricultural productivity, enhance health outcomes, and provide sustainable solutions to environmental challenges.
Molecular techniques in plant sciences
Molecular techniques in plant sciences
DNA Isolation and Analysis
DNA isolation is a fundamental step in molecular biology that allows for the extraction of genetic material from plant tissues. Techniques such as CTAB method, phenol-chloroform extraction, and silica gel-based methods are commonly used. Following isolation, techniques like PCR (Polymerase Chain Reaction) and gel electrophoresis are employed for DNA analysis, allowing researchers to amplify and visualize specific DNA sequences.
Genetic Transformation Techniques
Genetic transformation involves the introduction of foreign DNA into a plant's genome. Methods include Agrobacterium-mediated transformation, where the bacterium transfers T-DNA into the plant cells, and biolistic method (gene gun), where DNA-coated particles are physically delivered into plant cells. These techniques are critical for producing transgenic plants with desired traits.
Molecular Markers and Phylogenetics
Molecular markers such as SSR (Simple Sequence Repeats), RAPD (Random Amplified Polymorphic DNA), and SNPs (Single Nucleotide Polymorphisms) are used for genetic mapping, diversity studies, and phylogenetic analysis in plants. These markers provide insights into genetic relationships and evolutionary patterns among different plant species.
CRISPR-Cas9 Technology
The CRISPR-Cas9 system is a revolutionary gene-editing technology used to create precise modifications in the plant genome. This technique allows for targeted deletions, insertions, and modifications of specific genes. Its applications include developing disease-resistant plants, improving yield, and enhancing nutritional quality.
Molecular Breeding
Molecular breeding combines traditional breeding methods with molecular biology tools. Techniques such as marker-assisted selection (MAS) enable breeders to select plants with desired traits more efficiently. This approach accelerates the development of improved plant varieties with greater yield, resilience, and nutritional value.
