Role Of Proteins

Proteins are the metabolic workhorses of the cell; they engage in a variety of essential activities ranging from enzymatically catabolizing macromolecular food sources to serving as structural components that maintain cell stability. Maximizing protein function relies on intricate non-covalent interactions occurring on the secondary, tertiary, and quaternary levels that help determine the overall shape of the protein. In their native states, proteins will assume the most energetically favorable configuration. Occasionally however, cells are exposed to exogenous disruptions such as heat stress. Heat Stress can compromise protein three-dimensional structure. Hydrophobic residues tend to be buried in the interior of the protein but when

A protein has multiple existing structures, these are the primary, secondary, tertiary and quaternary structures which occur progressively. A protein is essentially a sequence of amino acids which are bonded adjacently, and interact with one another in various ways depending on the R group that the amino acid contains. There are 20 different amino acids which are able to be arranged in any given order, thus giving rise to a potential 2.433x1018 (4.s.f) different combinations, and therefore interactions between the various amino acids.

their normal shape to an abnormal shape, however, the chemical composition of the protein remains

Proteins are primarily considered to have one primary function to serve its role in an organism, however studies have observed to have multiple functioning proteins known as moonlighting proteins (Khan et al. 2014). Moonlighting proteins along with primary functions, have secondary functions that are not related to the primary function and does not correlate to the primary or other functions (Khan et al. 2014). The multifunctional proteins play essential roles in carrying out biochemical functions which aids in the cell growth but are not caused by gene fusion and multiple RNA splice variants (Amblee et al. 2015). The discovery of moonlighting proteins was first discovered by Piatigorsky and Wistow while observing crystallins (Khan et al. 2014). Crystallins, are structural proteins that are found in the eye lens that exhibit enzymatic activity to make the lens itself (Khan et al. 2014). Crystallin has a primary function to help form the lens of the eye by acting as a structural protein (Amblee et al. 2015). Besides enzymatic activity, crystallin was observed in other mammals to have secondary functions such as metabolic functions which are helpful in prokaryotic (Khan et al 2014). Most moonlighting proteins are characterized as cytosolic enzymes and chaperons, or in other words helping proteins (Amblee et al 2015). The multifunctional proteins or moonlighting proteins can also be identified as receptors, channel proteins and ribosomal proteins (Khan et al. 2014). Due to the

The basic building blocks of proteins are amino acids, the biuret reaction tests for protein. A solution of sodium hydroxide is added to a sample then a few drops of copper sulphate solution, if positive – the solution will turn mauve. There are 20 different amino acids and they can be joined in any order. Therefore there can be many different functions. A protein consists of one or more polypeptide chains (a polypeptide chain being multiple amino acids joined together via condensation, producing a peptide bond). Different proteins have different shapes as the shapes are determined by the sequence of amino acids.

One wrong amino acid can change the shape of the protein and lead to a malfunctioning protein.

The amino acid sequences derived from decoding the mRNA determines a protein's final conformation, helper proteins aid the newly formed polypeptide with its folding to achieve a proper functional shape. These molecular chaperones are essential as the cytoplasm is often filled with new polypeptide chains and thus these accumulation of polypeptide chain might accumulate together and fold into a non-function shape. Example of well studied chaperones from E.Coli are DnaK, DnaJ, GroEL and GroES. And GrpE.

Proteins are made of amino acids, which are compounds built around a central carbon atom. Amino acids then join together through dehydration reactions. These are called peptide bonds. Many amino acids joined together are called polypeptides. A polypeptide becomes a protein when it folds into a three dimensional structure. This is the primary structure of a protein. The next structure in the hierarchy is the secondary structure. Secondary structures can either form alpha helixes, where an amino acid sequence forces the polypeptide to twist into a helical shape; or beta sheets, where an amino acid sequence forces the polypeptide into a zigzag shape. In the tertiary structure, the polypeptide folds several times on itself to form a more complex three dimensional shape. A quaternary structure is when two tertiary structures interact with each other. This is when a protein becomes a functional

Some proteins even have 3-dimensional shaping caused by disulfide bridges, ionic bonds, and van der Waals interactions. Within the folds of

Proteins are polymeric chains that are built from monomers called amino acids. All structural and functional properties of proteins derive from the chemical properties of the polypeptide chain. There are four levels of protein structural organization: primary, secondary, tertiary, and quaternary. Primary structure is defined as the linear sequence of amino acids in a polypeptide chain. The secondary structure refers to certain regular geometric figures of the chain. Tertiary structure results from long-range contacts within the chain. The quaternary structure is the organization of protein subunits, or two or more independent polypeptide chains.

Living organisms need proteins in their diet to help the body repair cells and make new ones. The basic structure of protein is a chain of amino acids. When two amino acids join together a dipeptide is formed but when more than two amino acids are joined together a polypeptide is formed. Proteins are made up of one or more polypeptides. Proteins are large molecules made up of the elements hydrogen, oxygen, nitrogen and carbon. Types of proteins include, structural proteins, contractile proteins, hormones, enzymes, antibodies and transport proteins. Some functions of proteins are movement in muscles, tendons and ligaments. Enzymes make biological reactions possible and hormones regulate metabolism. The protein shape determines its function.Proteins

With the aid of GFP, researchers have developed ways to watch processes that were previously invisible, such as the development of nerve cells in the brain or how cancer cells spread. Tens of thousands of different proteins reside in a living organism, controlling important chemical processes in minute detail. If this protein machinery malfunctions, illness and disease often follow. That is why it has been imperative for bioscience to map the role of different proteins in the body. “(The Nobel Prize in Chemistry 2008 - Press

The specific and unique order in the polypeptide chain is determined by the information from the cellular genetic code of the protein. Having one amino acid in the structure causes the amino acid to not function properly or at all. There are four levels of protein structures, the primary structure, secondary structure, tertiary structure, and quaternary structure. The primary structure explains the order of which the twenty amino acids in proteins are held together to form a proper protein. The following amino acid structural characteristics are, carbons, hydrogen atoms, and carboxyl groups. Alpha Carbon is a necessity to hydrogen atoms, carboxyl groups, and the amino groups in protein structures. The secondary structure causes the structure to fold, curve, and make loops, that gives the protein its' dimentinal shape. The two types of secondary structures are alpha helix structures and beta pleated sheet. The alpha helix structure looks like a coil and is bonded by multiple hydrogens. The beta pleated sheet is folded and held together by hydrogen bonds in between polypeptide units. The third level, the tertiary structure is a broad dementinal structure that has several types of bonds and forces to keep the protein in tact. The shaping of a protein is caused by the hydrophobic interactions. Amino acids and hydrophilic will make a great amount of contact with their

Bettelheim, Brown, Campbell and Farrell assert that polypeptide chains do not extend in straight lines but rather they fold in various ways and give rise to a large number of three-dimensional structures (594). This folding or conformation of amino acids in the localized regions of the polypeptide chains defines the secondary structure of proteins. The main force responsible for the secondary structure is the non-covalent

Chaperones are one of the ways that the body can help to regulate the folding of proteins. Chaperones can work alone or with cochaperones in order to assist with the folding, disaggregation, degradation, and trafficking within the cell(Labbadia et al., 2015). Because chaperones are so important for the cell’s existence, expression of chaperones is often increased with cellular stress. The unfolded protein response (UPR) in another process that cells undergo to make sure that proteins are folded correctly. This process can take place in the cytoplasm, the endoplasmic reticulum, and the mitochondria. If there is a buildup of unfolded proteins in the cell, the unfolded protein response kicks in and activates intracellular signal