Folding and Aggregation Essay Example | Topics and Well Written Essays - 1000 words

Folding and Aggregation - Essay Example The three dimensional structures of proteins aid in delineating protein functions at a molecular level and the structure of proteins are determined usually with X ray crystallography, NMR spectroscopy etc. Some structural features of proteins would be necessary to perform certain biochemical functions although multifunctional and structural proteins may have higher number of residues than the average of 300 residues. Large aggregates are formed as a result of folding from protein subunits and actin molecules also assemble into actin filaments. The protein structure has four distinct features including amino acid sequence of peptide chains as seen in a primary structure, secondary structures which are regular sub structures, such as strands of beta sheet, tertiary structure as seen in the three dimensional structure of a single protein molecule and quaternary structure which represents a complex of polypeptide chains and protein molecules (Copley, 1997; Berg, 2002). Proteins tend to transition between structures to perform the biological functions and this would be known as conformational changes. The primary structure of proteins with amino acid sequences would be held together by covalent peptide bonds and the extremities of the amino acid chains are known as carboxy terminus (C - terminus) and amino terminus ( N -terminus). The secondary structures are defined by their patterns of hydrogen bonds between the peptide groups although these bonds are generally not too stable except in conditions when the water concentration is low as in molten globule or fully folded states (Urbanc et al, 2006). The non specific interactions and propensities of amino acids would lead to the formation of molten globules. The tertiary structure shows structurally specific interactions within the protein domain with side chains and hydrogen bonds. The disulfide bonds tend to stabilize the tertiary structures of extra cellular proteins and reduce entropy in an unfolded state. The 4 levels of protein structure are given diagrammatically as follows - Figure I - From Columbia.edu, biology courses, 2005 handouts The formation of proteins could be explained as the combination of two amino acids in a condensation reaction and long chains of residues such as amino acids in peptide bond. The sequence of amino acids forms the primary structure of the peptide or protein and is determined by a gene. Within the primary structure, a sequence of nucleotides in DNA is transcribed into mRNA and this is translated by a ribosome and the sequence tends to define the structure and functions of the protein and would be unique to any specific protein. Determining the sequence of nucleotides within the primary structure would actually help in defining the protein (Berg, 2002; Copley, 1997). In the secondary structure, alpha helix and beta sheet saturate the peptide and secondary structures tend to occur most frequently in most proteins. The secondary structure elements tend to have a regular geometry with specific values and are usually folded into a shape with loops and turns (Berg, 2002, Copley, 1997). Terti ary structures are formed with interactions such as hydrogen bonding and ionic interactions and

Research paper for Health Economics Example | Topics and Well Written Essays - 1750 words

For Health Economics - Research Paper Example If the medical profession is viewed as health care service being a public or civic activity, it can capture the true purposes of the service. The ethical practices of health care is a strong debate in this field of study and incorporates both the commercial aspects as well as the social and ethical aspects of health policies, health reforms, and moral medical practice meaningfully (Jennings and Hanson). 3 Introduction Health care is a debated topic in the current decade and the discussion over today's health care system revolves around the views that consider â€Å"health care services as commodities† (Jennings and Hanson). These debates involve discussions about how reforms can be brought about in this sector. This point of view takes care of the economic objectives of the reforms in the health care system but obscures the other portion of the purposes of providing efficient health care: the morally vital attributes of the medical profession and the health care provision. If the medical profession is viewed as health care service being a public or civic activity, it can capture the true purposes of the service. ... The price of these products and their availability are specific characteristics making them similar to other normal economic commodities. Although these characteristics are advantageous for some consumers in the US that have coverage of health insurance and also for those that manufacture medicines and medical equipment, the specificity of the characteristics places other parties, such as uninsured consumers and the government, at a disadvantageous position. Racial disparities play an important role in the status of the health care system in the US and are considered as an unrelenting and disconcerting problem for the country. Health status of the average population in a country reflects the economic health of the country, and it is a serious problem since ample policy efforts have yet not been able to rectify the situation. On the contrary, African-Americans and other ethnic and racial minorities are often reported to receive less than the desired level of care. The quality of medic al attention also differs from the care received by their white skinned counterparts (Jha). This makes the situation worse. The hypothesis made in this context is that racial disparities can be eliminated and a better health care system can be established in the States. The questions studied through this research are: what causes these disparities to exist and what steps might be taken in order to do away with the gap and reduce the disproportion in the country’s health system. The study has been carried out by collecting secondary data and making qualitative analysis of the same. Secondary resources available on online and print media such as books, journals, newspapers and online articles,