Macromolecules Handouts (PDF)

CARBOHYDRATES MALTOSE – aka malt sugar ; 2 glucose molecule - malted cereals & sprouting grain...

CARBOHYDRATES MALTOSE – aka malt sugar ; 2 glucose molecule - malted cereals & sprouting grain SUCROSE – aka table sugar;glucose and fructose - sugarcane, sugar beets,carrots &other sweet fruits 3. POLYSACCHARIDES ( C₆ H₁ₒ O ₅) A long chain of monosaccharides linked by glycosidic bonds is known as a polysaccharide 1.monosaccharides (mono- = A. STORAGE POLYSACCHARIDE “one”; sacchar- = “sugar”) EXAMPLES  simple sugars, the most common of which STARCH – sugar in plants compose of is glucose. Monosaccharides have a glucose molecule ( potato tubers, formula of (C₆H₁₂O₆)and they typically cassava, corn & cereals) contain three to six carbon atoms GLYCOGEN – sugar storage in animals  monomer of carbohydrates Glycogen is usually stored in liver and  Named according to number of carbon muscle cells. Whenever blood glucose atoms levels decrease, glycogen is broken 2. DISACCHARIDES ( C₁₂ H₂₂ O₁₁ ) down via hydrolysis to release glucose  Formed when two monosaccharides monomers that cells can absorb and join together via a dehydration use. reaction, also known as a condensation B. STRUCTURAL reaction or dehydration synthesis. POLYSACCHARIDES EXAMPLES  hydroxyl group of one monosaccharide Cellulose, for combines with the hydrogen of example, is a major another, releasing a molecule of water component of and forming a covalent bond known as a plant cell glycosidic linkage. walls, which are rigid structures that enclose the cells (and help make lettuce and other veggies crunchy). Wood and paper The β glycosidic linkages in cellulose can't be broken by human digestive enzymes, so humans are not able to digest cellulose. (That’s not to say that cellulose isn’t found in our diets, it just passes through us as undigested, Examples insoluble fiber.) LACTOSE - consist of glucose and CELLULASE enzyme can break down cellulose(ruminants, termites) galactose and is found naturally in CHITIN – makes up exoskeleton of milk arthropod - lactose intolerance  - also found in cell walls of fungi SATURATED FATTY ACID Single bond between neighboring carbons in hydrocarbon chain. LIPIDS Saturated with hydrogen Means “fat” Solid at room temp Hydrophobic, nonpolar & made up of High melting point HYDROCARBON CHAIN Animal fat Glycerol & fatty acid is the monomer UNSATURATED FATTY ACID Functions When hydrocarbon has one or more double 1. Insulation bond 2. Store & produce energy Chain bend at double bond 3. Make up cell membrane Fewer hydrogen Liquid @ room temperature 4. Prevents water loss Found in plants 5. Solvent for fat soluble vitamins & hormones Examples of unsaturated fatty acid Palmitoleic acid Consist of Oleic acid a. glycerol backbone Linoleic acid –organic molecule Trans fat with 3 hydroxyl (OH)group Cis fat b. Fatty acid –long Omega-3-fatty acid hydrocarbon chain attached to carboxyl TRANS FAT group (12-18 Rare in nature but produced by partial carbons) hydrogenation Hydrogen gas is passed to through oils How to make fat converting it from double bond to molecule/triglyceride/triglycerol single bond Hydroxyl group on the glycerol backbone To give oil solidity @ room temp. reacts with carboxyl group of fatty acid in Negative effect –coronary heart a DEHYDRATION SYNTHESIS disease Results to fat molecule with 3 fatty acid tails bound to glycerol backbone via ESTER LINKAGE (ESTER BOND) and release 3 molecules of H₂O stored in fat cell called ADIPOCYTES that makes up adipose tissue OMEGA-3 FATTY ACID – reduce risk of heart attack, decrease triglycerides, lower blood pressure & prevent formation of clots. STEROID four linked carbon rings Hydrophobic and insoluble in water. Example is cholesterol  CHOLESTEROL Most common steroid  20 types of amino acid found in ( Syntehsized in the liver ) Protein the precursor to  Every amino acid also has another atom or group steroid hormone ( of atoms bonded to the central atom, testosterone & estradiol known as the R Starting material for vit D and bile acid group, which (absorption of fats) determines the Important in cell membrane ( fluidity) identity of the amino acid. ; Found in the blood stream ( LDL & HDL)  if the R group is a hydrogen atom, then the amino acid is glycine The properties of MACROMOLECULE (PROTEIN) the side chain  amino acids-monomer determine an amino  all proteins are made up of one or more linear acid’s chemical chains of amino acids called polypeptide behavior (that is,  amino acids of a polypeptide are attached to their whether it is neighbors by considered acidic, covalent basic, polar, or bonds known as nonpolar). For a peptide example, amino bonds. acids such as valine and leucine are nonpolar and hydrophobic, while amino acids like Each bond forms in a dehydration synthesis serine and (condensation) reaction. During protein synthesis, glutamine have the carboxyl group of the amino acid at the end of hydrophilic side the chains and are growing polar. Some amino polypeptide chain acids, such as lysine and arginine, have side reacts with the chains that are positively charged at physiological amino group of pH and are considered basic amino acids. an incoming amino acid, (Histidine is sometimes put in this group too, although releasing a it is mostly deprotonated at physiological pH.) molecule of Aspartate and glutamate, on the other hand, are water. The negatively charged at physiological pH and are resulting bond considered acidic between amino acids is a LEVEL OF STRUCTURE OF PROTEINS peptide bond. At one end, the polypeptide has a free amino group, and this end is called the amino 1. PRIMARY- simplest terminus (or N-terminus). The other end, which has a -order of amino acid in the polypeptide chain free carboxyl group, is known as the carboxyl (sequence of a protein is determined by the DNA of the terminus (or C-terminus). The N-terminus is on the left gene that encodes the and the C-terminus is on the right for the very short protein) polypeptide shown above. -In sickle cell anemia- one  consist of a central carbon atom ( alpha carbon) of the amino acid bonded to an amino group, carboxyl group and a ( glutamic acid) that hydrogen atom makes up the polypeptide chain of hemoglobin is replaced by the amino acid valine. This causes a change in the shape of the red blood cell.  said to be denatured. Denatured proteins 2. Secondary- refers to are usually non-functional. the folded structures that form within a polypeptide For some proteins, denaturation can be due to interactions between atoms of the reversed. Since the primary structure of the backbone. (The polypeptide is still intact (the amino acids backbone just refers to haven’t split up), it may be able to re-fold the polypeptide chain into its functional form if it's returned to its apart from the R groups normal environment. Other times, however, -held in shape by denaturation is permanent. One example of hydrogen bond irreversible protein denaturation is when an Examples are the α helix and the β pleated sheet egg is fried. The albumin protein in the liquid egg white becomes opaque and solid as it is 3. Tertiary- three-dimensional structure of a denatured by the heat of the stove, and will polypeptide.Primarily due to interactions not return to its original, raw-egg state even between the R groups of the amino acids when cooled down. that make up the protein. R group interaction Many proteins don’t fold by themselves, but Include hydrogen bonding, ionic bonding, instead get assistance dipole-dipole interactions, and London from chaperone proteins (chaperonins). dispersion forces (non-covalent bonds).Disulfide bond is the only covalent Types & Function of Proteins bond that contribute to tertiary structure. 1. ENZYMES act as catalysts in biochemical 4. QUARTERNARY- multiple polypeptide chains, reactions, meaning that they speed the reactions up. Each enzyme recognizes one or more also known as subunits come together. substrates, Example: hemoglobin, DNA Polymerase Substrate- the molecules that serve as starting material for the reaction. Different enzymes participate in different types of reactions and may break down, link up, or rearrange their substrates. One example of an enzyme found in your body is salivary amylase, which breaks amylose (a kind of starch) down into smaller sugars. The amylose doesn’t taste very sweet, but the smaller sugars do. This is why starchy foods often taste sweeter if you chew them for longer: you’re giving salivary amylase time to get to work. 2. HORMONES - long-distance chemical signals released by endocrine cells (like the cells of your pituitary gland). They control specific physiological processes, such as growth, development, metabolism, and DENATURATION & PROTEIN FOLDING reproduction. Each protein has its own unique shape. If While some hormones are steroid-based the temperature or pH of a protein's (lipids) others are proteins. These protein- environment is changed, or if it is exposed based hormones are commonly called to chemicals, these interactions may be peptide hormones. disrupted, causing the protein to lose its three-dimensional structure and turn For example, insulin is an important peptide back into an unstructured string of amino hormone that helps regulate blood glucose acids. When a protein loses its higher-order levels. When blood glucose rises (for structure, but not its primary sequence, it is instance, after you eat a meal), specialized cells in the pancreas release insulin. The insulin binds to cells in the DNA contains one of four possible liver and other parts of the body, nitrogenous bases: adenine (A), guanine (G) causing them to take up the glucose. cytosine (C), and thymine (T). This process helps return blood sugar to its normal, resting level. Purines -Adenine and guanine --structure contain two fused carbon- Protein types and functions nitrogen ring. Pyrimidine – Cytosine , Thymine & Uracil Role Examples Functions -- single carbon-nitrogen ring. Break down nutrients in food RNa contains one of four possible Amylase, into small pieces nitrogenous bases: adenine (A), guanine (G) Digestive lipase, that can be cytosine (C), and uracil (U). enzyme pepsin readily absorbed 2. SUGAR (five carbon Sugar) Carry DNA – deoxyribose RNA -ribose substances  the second carbon of ribose bears a throughout the hydroxyl group, while the equivalent body in blood or carbon of deoxyribose has a hydrogen Transport Hemoglobin lymph instead. Actin, Build different  The carbon atoms of a nucleotide’s sugar tubulin, structures, like molecule are numbered as 1′, 2′, 3′, 4′, Structure keratin the cytoskeleton and 5′ (1′ is read as “one prime”), as Coordinate the shown in the figure below. In a activity of nucleotide, the sugar occupies a Hormone Insulin, different body central position, with the base signaling glucagon systems attached to its 1′ carbon and the Protect the body phosphate group (or groups) from foreign attached to its 5′ carbon. Defense Antibodies pathogens Carry out Contracti muscle on Myosin contraction Legume Provide food for storage the early proteins, development of egg white the embryo or Storage (albumin) the seedling MACROMOLECULE (NUCLEIC ACID) DNA and RNA are polymers (in the case of DNA, often very long polymers), and are made up of monomers known as nucleotides. When these monomers combine, the resulting chain is called a polynucleotide. (DNA deoxyribonucleic acid and RNA ribonucleic acid ) 3. PHOSPHATE- Nucleotides may have a single phosphate group, or a chain of Nucleotide is made up of three parts: up to three phosphate groups, attached to the 5’ carbon of the sugar 1. NITROGENOUS BASE- organic carbon POLYNUCLEOTIDE CHAINS – has based nitrogen-containing ring structure directionality ( two ends are different from each other)  At the 5’ end, or beginning, of the chain, --single-stranded. A nucleotide in an RNA the 5’ phosphate group of the first chain will contain ribose (the five-carbon nucleotide in the chain sticks out. At the sugar), one of the four nitrogenous bases (A, other end, called the 3’ end, the 3’ U, G, or C), and a phosphate group hydroxyl of the last nucleotide added to MESSENGER RNA (mRNA) the chain is exposed. --intermediate between a protein-coding DNA sequences are usually written in gene and its protein product. If a cell the 5' to 3' direction, meaning that the needs to make a particular protein, the gene nucleotide at the 5' end comes first and the encoding the protein will be turned “on,” nucleotide at the 3' end comes last. meaning an RNA-polymerizing enzyme will As new nucleotides are added to a strand of come and make an RNA copy, or transcript, DNA or RNA, the strand grows at its 3’ end, of the gene’s DNA sequence. with the 5′ phosphate of an incoming  The transcript carries the same nucleotide attaching to the hydroxyl group at information as the DNA sequence of its the 3’ end of the chain. This makes a chain gene. However, in the RNA molecule, the with each sugar joined to its neighbors base T is replaced with U. For instance, if by a set of bonds called a DNA coding strand has the sequence 5’- a phosphodiester linkage. AATTGCGC-3’, the sequence of the corresponding RNA will be 5’-AAUUGCGC- PROPERTIES OF DNA 3’. - Double helix (structure in which two matching (complementary) chains are  Once an mRNA has been produced, it will stuck together associate with a ribosome, a molecular machine that specializes in assembling  The sugars and phosphates lie on the proteins out of amino acids. The ribosome outside of the helix, forming the uses the information in the mRNA to backbone of the DNA; this portion of the make a protein of a specific sequence, molecule is sometimes called the sugar- “reading out” the mRNA’s nucleotides in phosphate backbone. groups of three (called codons) and adding a particular amino acid for each  The nitrogenous bases extend into the codon. interior, like the steps of a staircase, in pairs; the bases of a pair are bound RIBOSOMAL RNA (rRNA) to each other by hydrogen bonds. --a major component of ribosomes, where it helps mRNA bind in the right spot so its sequence information can be read out. Some rRNAs also act as enzymes, meaning that they help accelerate (catalyze) chemical reactions – in this case, the formation of bonds that link amino acids to form a protein. RNAs that act as enzymes are known as ribozymes. Transfer RNAs (tRNAs) --are also involved in protein synthesis, but their job is to act as carriers – to bring amino acids to the ribosome, ensuring that the ANTI-PARALLEL- two strands of the helix amino acid added to the chain is the one run in opposite directions, meaning that the specified 5′ end of one strand is paired up with the 3′ by the end of its matching strand. mRNA. Transfer RNAs consist of a single PROPERTIES OF RNA strand of RNA, but this strand has complementary segments that stick together to make double-stranded regions. This base-pairing creates a complex 3D structure important to DNA RNA the function of the molecule. Involved in protein SUMMARY FEATURES OF DNA &RNA synthesis and gene regulation; carrier Functio Repository of genetic n of genetic information in some information viruses Sugar Deoxyribos e Ribose Structu re Double Usually single- helix stranded Bases C, T, A, G C, U, A, G