De-oxy-ribonuclease enzyme - Research Paper Example

Proteins play critical roles in the cell, a factor that has helped scientists appreciate the salient significance of these molecules. Some cell proteins serve as enzymes, a role that involves the catalysis of all cellular processes. Proteins exhibit a high level of specialization, a factor that is evident in the structure and function of enzymes in the cell. Moreover, depending on the functions, proteins exhibit diverse structural adaptations. The role played by enzymes cannot receive any form of underestimation because cells would be unable to run processes at the required speed, and this would retard growth processes (Petsko&Ringe, 2004).

Otherproteins are structural and include keratin, silk, ligaments, and tendons. There is also evidence that proteins are of significant use as contractile molecules. In, addition, proteins play a critical role in the immunes system as antibodies that recognize antigens and work towards eliminating them. Proteins are also critical in cell transport. Cells interactions and processes require signal both signal molecules and receptors, and biologists have identified such critical molecules as proteins.

Structure of Proteins Proteins exhibit four different levels of their structure. It is worth noting that the basic components of proteins are amino acids. Scientists have described the existence of twenty different amino acids that are critical in building the wide range of proteins that perform the functions described above. The order and number of the amino acids making up each protein depend on the role played by each protein. Moreover, there is variation of protein structure across different species (Rigden, 2009).

The simplest level of protein structure is the primary structure defined by its linear sequence of all the amino acids making up a certain protein, listed in three letter word abbreviations. This being the simplest form of any protein helps in highlighting the individual amino acids making up each chain. Usually, the linkage between these amino acids is through covalent bonds that define the peptide bond existing between the amino acids. The second level of protein structure is the secondary structure characterized by the formation of regular structures that biochemists have described as helices and beta sheets.

Hydrogen bonds facilitate the formation of such regular structures within the lengthy polypeptide chains of amino acids (Buxbaum, 2007. The hydrogen bonds only occur between carbon and oxygen molecules and between hygrogen and nitrogen molecules. Helices have been described as loose coils of amino acids with each turn consisting of three amino acid residues and additional atoms from the next amino acid. The coiling in alpha helices occurs in a clockwise direction. On the other hand, beta sheets have polypeptide chains folded in a manner that makes the regular structures be enjoined alongside each other.

The third level of the protein structure is a three dimensional representation of all the polypeptide chains and other secondary structures. The structure remains in place because of ionic interactions, hydrogen bonds, sulfur bridges, and van der waals forces. The fourth level of structure is the quaternary structure defined by a specific complex shape taken by the different polypeptide chains with different forces holding up the structure (Whitford, 2005). Figure one Levels of Protein Structure De-oxy-ribonuclease This is one of the critical enzymes found in both higher