Dna Protein Protein Structure

Proteins are complex structures made up of chains of amino acids. Each protein has a different function such as enzymes to catalyze reactions or protein hormones to trigger certain functions of a cell. First let’s start with the most basic component of a protein: an amino acid. An amino acid is made up of a central carbon atom attached to a hydrogen atom, a carboxyl group, an amino group, and an R group which varies

The structure of an enzyme as protein has a primary, secondary, tertiary, and sometimes quaternary structure. The primary structure of an enzyme, like any protein, is the order of its amino acids. The secondary structure involves alpha helices and beta pleated sheets. Alpha helices are a coil that is formed by hydrogen bonding between every fourth amino acid. Beta pleated sheets are formed by hydrogen bonding between two or more parts of the polypeptide chain that are side by side. The tertiary structure contains disulfide bridges, ionic bonds, hydrophobic interactions, and hydrogen bonds. Disulfide bridges are the result of two sulfhydryl groups interacting because the the folding of the protein. Ionic bonds can form between polar groups on amino acids. Hydrophobic interactions are the cluster of amino acids with nonpolar side chains that is commonly seen in proteins. Hydrogen bonds can also form. The quaternary structure of an enzyme is when multiple proteins are bonded together in one complex made of proteins subunits.

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.

Enzymes are a specific kind of protein that usually act to enhance a chemical reaction. Enzymes, like any other protein, are made of amino acids arranged in a specific pattern that in transcribed through mRNA and translated in the nucleus by the ribosomes. The basic amino acid chain is called the primary structure, the chain usually undergoes bonding that results in either an Alpha helix structure or a Beta sheet structure depending on the function of the enzyme and the interactions between the amino acids. Further interaction will result in a 3D conformation which is called a tertiary structure, which are the functioning subunits of an enzyme. As subunits come together to form an enzyme, that is a quaternary structure.

The PBGD polypeptide chain consists of 313 amino acids and is approximately 57 x 43 x 32 Å in size. Crystal structure of PBGD revealed a highly flexible protein with three equally sized α/β domains. The N terminal domain (domain 1) and the central domain (domain 2) have similar structures, both being doubly wound parallel beta sheets. Domain 3 (C terminal) is an open faced, anti-parallel, three stranded beta sheet with one side covered in 3 alpha helices, this domain interacts with both 1 and 2. In domains 1 and 2, each sheet has 4 parallel and 1 anti parallel strand with alpha helical segments packed against each face and are orientated parallel to one another. Domains 1 & 2 are motifs and they are both related by a two-fold axis. Domain

Protein is a compound that’s made up of amino acids that are joined by peptide bonds. It is considered the most important molecule which can come in two forms, complete proteins and incomplete proteins.

Task 2b: A series of diagrams, with clear labels, of the different levels of protein structure (i.e. Primary, Secondary, Tertiary, Quaternary).

The body makes many different types of proteins, each of which has a specific job. Oftentimes, the shape of the protein molecule is what allows it to do its unique job. A protein molecule is made up of a string of amino acids and each of these amino acids has a net positive, negative, or neutral charge. If two adjacent amino acids on the string both have a positive charge or both have a negative charge, then will repel each other and force each other to move apart. If one has a negative charge and the other a positive charge, they will move closer together. Thus all that pushing and pulling will determine the ultimate shape of the molecule. (Fowler, 2013)

The four levels of protein structure are primary, secondary, tertiary, and quaternary. All of the levels are made from the primary structure of the protein. Primary structure contains covalent bonds and is the foundation and basis for the other levels of a protein. Secondary structure is a repeated continuation of a peptide chain.

In 1979 Nobel prize laureate and the co-discoverer of the structure of DNA called for a precise method to gain control over specific classes of neurones “leaving the others more of less unaltered” which will allow us to understand more about the “profoundly mysterious brain.” This was the first articulated idea of optogenetics, which would lead to the development of one of the most exciting areas of neuroscience. In 2005 Karl Desseroth and Ed Boyden publishes a paper detailing a single optogenetic system a revolutionary paper, using channel rhodopsin

A triplet is a group of 3 DNA nucleotides. A codon is a group of 3 RNA nucleotides. Triplets code for codons, codons code for anticodons in the tRNA, which brings the amino acids.

Campbell and Farrell define proteins as polymers of amino acids that have been covalently joined through peptide bonds to form amino acid chains (61). A short amino acid chain comprising of thirty amino acids forms a peptide, and a longer chain of amino acids forms a polypeptide or a protein. Each of the amino acids making up a protein, has a fundamental design that comprises of a central carbon or alpha carbon that is bonded to a hydrogen element, an amino grouping, a carboxyl grouping, and a unique side chain or the R-group (Campbell and Farrell 61).

It is said that the process of protein synthesis is controlled by the DNA molecules. Proteins are used for growth and repair, as well as enzymes. Thus, DNA is able to apply some controlling influence over the cells as a whole, and ultimately the organism as well. In DNA, the segments which hold the vital key to this process are referred to as the genes.

DNA (deoxyribonucleic acid) is a self-replicating nucleic acid that carries the genetic information in cells in a double helix structure. The 2 stranded helix is composed of 4 nucleotides, Adenine (A), Thymine (T), Guanine (G), and Cytosine (C). The base pairs only form between A and T connected by 2 Hydrogen bonds and G and C connected by 3 hydrogen bonds. Foremost DNA wrapping comes about as DNA wraps around protein called histones. These combined loops of DNA and protein are called nucleosomes and the nucleosomes are packaged into a thread called chromatin. Chromosomes are made up of packaged chromatin and can be seen in the nucleus of dividing cells and form around DNA replication. Furthermore, DNA replication begins with 2 DNA strands being separated by the helicase enzyme. Single stranded DNA binding proteins attach to these strands to keep them from re-connecting. 1 DNA strand begins to encode called the leading strand, which Forms from 5’ to 3’ end using DNA polymerase 3 the primary polymerase. The other strand is referred to as the lagging strand, which presents problems because it has to form from the 5’ to 3’end as well. As continuous replication of the leading strand continues the lagging strand forms in pieces called Okazaki fragments. RNA primase forms as RNA primer and polymerase III lay down new DNA. This process repeats again and again. DNA polymerase I replaces RNA primers with DNA and DNA ligase links the Okazaki fragments. Along with the process of DNA

When first discussing the protein itself we should understand the components of a protein by structure and function. Proteins are considered biological, organic polymers made of amino acids. Amino acids which are connected by peptide bonds to create a polypeptide chain. One or more polypeptide chains can become twined into a 3-D shape forming a protein. Proteins have many complex shapes that comprise of many loops, curves, and folds. Folding in proteins usually happens in a spontaneous manner. Chemical bonding consists of portions of the polypeptide chain holding the protein in one and giving it its shape. There are two general classes of protein molecules: globular proteins and fibrous proteins. Globular proteins are usually soluble, spherical in shape, and compact. Fibrous proteins are mostly elongated and insoluble. Globular and fibrous proteins may display one or more of four types of protein structure. These structured orders are called primary, secondary, tertiary, and quaternary structures. The 4 levels of protein structure are distinguished from one another by the degree of complexity in the polypeptide chain. A single protein molecule may include one or more of the protein structure types. The primary structure is best described as the unique order in which amino acids are joined together to form a protein. Proteins are constructed from a set of twenty amino acids.