* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Assignment No: One (1) Student details: Chebo
Survey
Document related concepts
Magnesium transporter wikipedia , lookup
Expression vector wikipedia , lookup
Ancestral sequence reconstruction wikipedia , lookup
Amino acid synthesis wikipedia , lookup
Genetic code wikipedia , lookup
Butyric acid wikipedia , lookup
Point mutation wikipedia , lookup
Interactome wikipedia , lookup
Biosynthesis wikipedia , lookup
Western blot wikipedia , lookup
Protein purification wikipedia , lookup
Basal metabolic rate wikipedia , lookup
Two-hybrid screening wikipedia , lookup
Metalloprotein wikipedia , lookup
Protein–protein interaction wikipedia , lookup
Fatty acid metabolism wikipedia , lookup
Fatty acid synthesis wikipedia , lookup
Transcript
INFORMATION AND COMMUNICATIONS UNIVERSITY SCHOOL OF ENGINEERING BIOLOGICAL CHEMISTRY An assignment submitted in partial fulfillment of the requirements for the BA Degree in AGRICULTURAL SCIENCES Assignment No: One (1) Student details: Chebo Mukandawire Student Identity No: 1608119912 Lecturer’s Name: Mr. Muvwanga Maxon Year: 1st 1. What are saturated and unsaturated fatty acids? Saturated fatty acids are fats that contain no double bonds between the carbon atoms, so it is saturated with hydrogen. This is the technical terminology. The important thing to remember is that saturated fatty acids are fats that cannot break down in the body and therefore, collect in places in the body and get stored. As saturated fatty acid collects within the body, it wreaks havoc and causes detrimental health issues. Some examples of saturated fatty acids are: lauric, myristic, palmitic and stearic acids. These saturated fatty acids can be found in certain food choices that should be limited or avoided altogether. A fat is made of two kinds of smaller molecules: monoglyceride and fatty acids. Fats are made of long chains of carbon (C) atoms. Some carbon atoms are linked by single bonds (-C-C-) and others are linked by double bonds (-C=C-).Double bonds can react with hydrogen to form single bonds. They are called saturated, because the second bond is broken up and each half of the bond is attached to (saturated with) a hydrogen atom. Most animal fats are saturated. The fats of plants and fish are generally unsaturated. Saturated fats tend to have higher melting points than their corresponding unsaturated fats, leading to the popular understanding that saturated fats tend to be solids at body temperatures, while unsaturated fats tend to be liquid oils. Various fats contain different proportions of saturated and unsaturated fat. Examples of foods containing a high proportion of saturated fat include animal fat products such as cream, cheese, butter, other whole milk dairy products and fatty meats which also contain dietary cholesterol. Certain vegetable products have high saturated fat content, such as coconut oil and palm kernel oil. Many prepared foods are high in saturated fat content, such as pizza, dairy desserts, and sausage. The effect of saturated fat on risk of disease is controversial. Many reviews recommend a diet low in saturated fat and argue it will lower risks of cardiovascular diseases, diabetes, or death.[5] However, other reviews have rejected those arguments or advocated for examining the proportion of saturated to unsaturated fat in the diet. Some common examples of fatty acids and chemical structures: Propionic acid Propanoic acid CH3CH2COOH Butyric acid Butanoic acid CH3(CH2)2COOH Valeric acid Pentanoic acid CH3(CH2)3COOH Caproic acid Hexanoic acid CH3(CH2)4COOH Unsaturated fat An unsaturated fat is a fat or fatty acid in which there is one or more double bond in the fatty acid chain. A fat molecule is monounsaturated if it contains one double bond and polyunsaturated if it contains more than one double bond. Where double bonds are formed, hydrogen atoms are eliminated. Thus, a saturated fat is "saturated" with hydrogen atoms. The greater the degree of unsaturation in a fatty acid (i.e., the more double bonds in the fatty acid), the more vulnerable it is to lipid peroxidation (rancidity). Antioxidants can protect unsaturated fat from lipid peroxidation. Foods containing unsaturated fats include avocado, nuts, and soybean, canola, and olive oils. Meat products contain both saturated and unsaturated fats. Unsaturated fats are liquid at room temperature. The following are examples of unsaturated there chemical structures: I. Myristoleic acid CH3(CH2)3CH=CH(CH2)7COOH II. Palmitoleic acid CH3(CH2)5CH=CH(CH2)7COOH III. Sapienic acid CH3(CH2)8CH=CH(CH2)4COOH 2. Based on the hydrolysis products of proteins, describe the three major classes of proteins. Proteins are naturally occurring polypeptides. They: contribute to the mechanical structure of animals, including humans, e.g. keratin in hair and fingernails, and fibrous proteins such as collagen in tendons enable animals to move, e.g. myosin in muscle facilitate transport of smaller molecules around animals' bodies, e.g. hemoglobin control the types and rates of chemical reactions in living things; then they are called enzymes, e.g. amylase are important components of the human immune system, e.g. immunoglobins Protein structures The sequence of amino acids in a protein is called its primary structure. Within a chain the atoms are held together by covalent bonds. Each protein has its own characteristic sequence of amino acids. Three types of bonding can happen within a protein molecule (intermolecular bonding) and between protein molecules (intermolecular bonding): Hydrogen bonds Covalent bonds Ionic bonds Protein chains arrange themselves to maximize the intra- and intermolecular bonding. The structure when protein chains are held in place is called the secondary structure. This may be: helical, e.g. keratin (the protein found in hair), or pleated sheet, e.g. fibroin (the protein found in silk) These structures are held in place by hydrogen bonds. Protein chains may fold into a globular shape. This is the tertiary structure of a protein. These globular proteins include enzymes and immunoglobins. The structures are held in place by hydrogen bonds, disulfide bridges and ionic bonds. The precise structure of a globular protein is the key to specificity of enzymes. Similarly proteins that act as receptor sites on the cell surface can recognize specific molecules because of their shapes. Finally some proteins have a quaternary structure. These contain more than one protein chain. Examples are insulin and hemoglobin. Try these websites for a good description of formation of peptides and their primary, secondary, tertiary and quaternary structures. Bibliography 1. Nelson DL, Cox MM (2005). Lehninger's Principles of Biochemistry (4th ed.). New York, New York: W. H. Freeman and Company 2. Gutteridge A, Thornton JM (2005). "Understanding nature's catalytic toolkit". Trends in Biochemical Sciences. 3. Dobson CM (2000). "The nature and significance of protein folding". In Pain RH. Mechanisms of Protein Folding. Oxford, Oxfordshire: Oxford University Press. pp. 1–28. 4. Fulton A, Isaacs W (1991). "Titin, a huge, elastic sarcomeric protein with a probable role in morphogenesis". BioEssays. 5. Bruckdorfer T, Marder O, Albericio F (2004). "From production of peptides in milligram amounts for research to multi-tons quantities for drugs of the future". Current Pharmaceutical Biotechnology. 6. Schwarzer D, Cole P (2005). "Protein semisynthesis and expressed protein ligation: chasing a protein's tail". Current Opinion in Chemical Biology. 7. Kent SB (2009). "Total chemical synthesis of proteins". Chemical Society Reviews. 8. Fernández A, Scott R (2003). "Dehydron: a structurally encoded signal for protein interaction". Biophysical Journal.