Proteins & Plasma Proteins PDF

Meaning they are long chains made of repeating By def: Proteins are Polymers of amino acids...

Meaning they are long chains made of repeating By def: Proteins are Polymers of amino acids amino acid units. Amino Acids Variety: Out of over 300 known amino acids, only 20 make up proteins Horses, cows, dogs, and cats: albumin predominates over globulin, -Others: the albumin-to-globulin ratio is equal. Newborn animals, except primates and rodents, have little to no gamma globulin at birth, making them more 6. Plasma Proteins in Animals They are covalent bonds between α-carboxylic susceptible to infections and α-amino groups **Peptide Bonds** Long chains of amino acids = peptides. Once a chain exceeds 50 amino acids, it's considered a Type I: Normally found in plasma protein. Proteins can consist of single or multiple polypeptide chains. (weight aa=110Da) They are Biological catalysts, two types Type II: Not usually present in plasma (increases indicate disease) The linear sequence of amino acids in a protein, Insulin was the 1st protein whose primary from the N-terminal to the C-terminal. It includes structure was fully determined. It consists of 2 Primary structure Tissue damage, synthesis rate of enzymes, the location of disulfide bonds (strong covalent chains (A and B) held together by disulfide delivery rate into blood, Inactivation or removal factors that can alter plasma enzyme activity 5. Enzymes bonds) that help stabilize the structure bonds. A has 21 amino acids, and B has 30. ALP (alkaline phosphatase): Bone diseases Refers to the spatial arrangement of aa due to Supersecondary Structure: clusters of 2nd hydrogen bonding. Common structures are the Secondary structure structures that act as intermediates between α-helix (spiral) and β-sheet (folded), both GGT (γ-glutamyl transferase): Liver diseases secondary and tertiary structures. enzymes are used as diagnostic markers for stabilized by hydrogen bonds specific diseases CK (creatine kinase):Muscle & bone diseases Hydrophobic Interactions: Hydrophobic (water-fearing) residues tend to be ALT & AST: Liver and heart diseases buried inside the protein, while ionizable residues (which interact with water) are found on the 1. Proteins The full 3D structure of a protein, bringing protein's surface Tertiary structure together aa that may be far apart in the primary Function: Maintains plasma osmotic pressure, sequence but are close in the folded structure. Several interactions stabilize the tertiary also transports fatty acids, bilirubin, and drugs 4. Albumin Proteins/Plasma **Structure/Function Relationship** structure, including: Disulfide bridges, Electrostatic interactions, Hydrogen bonds, If the level of albumin drops, fluid leaks into tissues, causing edema (swelling) **Clinical Importance:** proteins Hydrophobic interactions Some proteins have multiple subunits, and quaternary structure refers to how these Quaternary structure subunits assemble into a functional complex. In certain diseases, the distribution of plasma These subunits interact non-covalently. proteins changes. By comparing the electrophoretic pattern to the normal pattern, These proteins help other proteins fold we can detect disease conditions. Technique used to separate plasma proteins into different For a protein to become functional, it must fold Molecular chaperones correctly, especially under stressful conditions fractions. It helps study the distribution of proteins in the plasma and can be used to detect abnormal levels, aiding 3. Electrophoretic Analysis into its native, stable conformation. Incorrect (e.g., heat shock proteins) In response to infection, injury, or inflammation, in the diagnosis of diseases folding can lead to dysfunctional proteins and the levels of certain plasma proteins change can aggregate into amyloid fibers, contributing diseases Misfolded proteins significantly. These include: Complement to diseases like Parkinson's and Alzheimer's proteins, clotting factors, protease inhibitors, Protein Folding and Misfolding: Native vs. which help control tissue damage and necrosis. denatured state Denaturation occurs when proteins lose their structure due to heat, pH changes, or solvents. This leads to a loss of function. If denaturants are removed, some proteins can refold to regain Water in plasma helps in dissolving and 92% water, 7% proteins + organic and inorganic their function, showing that the aa sequence holds the **Composition of Plasma:** information for the proper 3D structure. transporting these proteins and compounds compounds Plasma proteins, especially albumin (80%), help regulate Spherical, water-soluble proteins (e.g., enzymes, 1-Osmotic pressure regulation Simple proteins (holoproteins) Only release aa upon hydrolysis Globular proteins osmotic pressure, ensuring proper fluid balance in the body. hemoglobin). Types of protein Proteins like fibrinogen are crucial for blood clotting 2-Clotting factors (coagulation) 2. Plasma Proteins Made up of both a protein part (apoprotein) and Long, insoluble proteins that form structural Conjugated proteins (heteroproteins) Fibrous proteins a non-protein part (prosthetic groups) frameworks (e.g., collagen, keratin). They carry molecules like hormones, lipids, and vitamins 3-Transporters Immunoglobulins help the immune system fight infections 4-Antibodies Several functions Certain proteins also function as hormones to regulate physiological processes. 5-Hormones Some proteins act as enzymes to catalyze biochemical reactions 6-Enzymes Blood buffering: Plasma proteins help buffer the blood’s pH to maintain the normal level of 7.4. 7-Other Source of amino acid: They can be broken down to provide aa for tissue synthesis.