Proteins and Amino Acids

• Amino acids are the building blocks of proteins.
• The bonding of two amino acids leads to water loss.
• Amino acids contain an ammonium (amino) group and a carboxylate (carboxylic acid) group; N-C-C is the backbone.
• All amino acids have the same base structure; they only differ in the R group.
• Amino acids can be classified based on their structure and properties.
• Some amino acids have nonpolar hydrocarbon side chains that are hydrophobic.
• Some amino acids have polar polar side chains that interact with water.
• Amino acids can be classified based on their properties.
• Amino acids contain a carboxylate (COO-) group, making them hydrophilic.
• Secondary Triple Helix consists of 3 polypeptide chains (crosslinks) found in collagen, connective tissues, skin, tendons, cartilage.
• Tertiary interactions involve nonpolar groups (hydrophobic), disulfide groups (bridges), hydrogen bonds, and ionic bonds.
• Globular proteins store and transport and have a compact, spherical shape.
• Quaternary refers to two or more protein units working together in the same reactions as tertiary.
• Secondary Beta Pleated is a side-by-side arrangement with hydrogen bonds present in fibrous proteins.
• Secondary Alpha Helix is a 3D spatial arrangement similar to a corkscrew held together by hydrogen bonds.
• Overall 3D shape of a protein has a pocket for oxygen.
• Amino acids contain an amino (NH2) group, making them hydrophilic.
• There are only 20 amino acids commonly found in the proteins of living organisms, which are called the essential amino acids.
• The essential amino acids are needed but cannot be synthesized by the body and must be obtained through diet.
• Cystine & Methionine are the only amino acids with sulfur.
• Hormone proteins regulate body metabolism and nervous system, example includes insulin.
• Peptides are composed of a carbonyl group and an amino group bonded by an amide bond, also known as a peptide bond.
• Transport proteins carry essential substances throughout the body, examples include hemoglobin and lipoproteins.
• Insulin was the first primary structure determined, it consists of 2 polypeptide chains linked by disulfide bonds.
• Storage proteins store amino acids, examples include casein.
• Contractile and Motor proteins make muscles move, examples include myosin and actin.
• In strongly alkaline conditions, pH > pI, NH3+ donates a proton.
• Enzymatic catalysts in biochemical reactions, examples include sucrase and trypsin.
• Structural proteins provide structural components such as collagen.
• Proteins are derived from the Greek word proteus (of first importance) and are the most prevalent types of molecule in living organisms, composed of amino acids linked by a peptide bond.