Essay on Prions the Proteinacious Killer

Creutzfeldt-Jakob Disease: It happens when a prion protein misfolds itself, thus causing a “domino effect” which unfolds itself causing a malfunction.

Proteinaceous Infectious Particles, commonly known as Prions, are extremely rare misfolds of the protein PrPc, which cause fatally neurodegenerative diseases, and are theorized to be infectious only by the protein itself (U.S National Library of Medicine, 1998). This “protein-only theory” is still heavily debated today, as some scientists deny the theory, and there isn’t a significant amount of evidence on each side to qualify the theory or disprove it (Soto, C. 2011). The base “Prion” protein is encoded in the gene PRNP, while being non-infectious. Prions are most commonly found in human prion diseases, but they can also be in other animals in the form of Mad Cow Disease and Chronic Wasting Disease, classified as Bovine Spongiform Encephalopathies

Humans have to deal with many different diseases and the ones most disliked are the ones with no cures. Like cancer, transmissible spongiform encephalopathies have no cure, but they are more rare. These diseases are prion diseases which cause the brain to deteriorate. Prions are proteins that sometimes behave like viruses, which mean that they should have some form of nucleic acid, but since they don’t, they cause abnormalities. The nervous system contains many normal prions, but when an abnormal prion comes along, it transforms all the normal prions into abnormal ones. Bovine spongiform encephalopathy is found in cattle, but it can be transmitted to humans.

     Mad Cow Disease, scientifically referred to as (BSE) Bovine Spongiform Encephalopathy, is a disease that affects those humans who eat the meat from infected cows. Mad Cow Disease is one of several fatal brain diseases called (TSE) Transmissible Spongiform Encephalopathy. (USDA) There was evidence of a new illness resembling the sheep disease scrapie. It was technically named BSE but quickly acquired the mad cow tag because of the way infected cattle behave. (CNN) In 1997, there was an award given to Stanley Prusiner, for concluding that a distorted protein called a prion was responsible for Mad Cow Disease, noted the long incubation period made it difficult to distinguish (Bryant).

In bovine spongiform encephalopathy (BSE), the disease is caused by the misfolding of proteins that cause proteins and peptides to develop a fibrillary structure. The PrPc is a correctly folded prion and the misfolded form is called PrPSc. BSE occurs when the normal PrPc come into contact with the toxic PrPSc and the normal prion takes on the shape of the PrPSc. The normal chaperones are unable to convert the PrPSc back to the normal form. The PrPSc now takes on the role of chaperone and the conversion of PrPc prions continue over and over. PrPSc, now being hydrophobic avoids the water of the inner cell and begin to accumulate and form plaques along the neuronal cell membranes. The aggregation of the prions on the cell membrane eventually lead to cell death which produces the sponge-like appearance in the brain of cattle infected with BSE (Thompson, 2014).

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.

Abnormal changes happen in the brain, and it appears as a sponge-like holes and gaps, causing deterioration in the areas of the brain. This can turn into spongiform degeneration that results in the progressive neurological and neuromuscular symptoms that are associated with CJD. This disorder is a result from a mutation in the gene that regulates the production of the human protein or direct transmission with abnormal protein in infected brain tissue. Scientist believe that there is a transmissible agent that is responsible for causing CJD. This is a slow virus, since it can take many years from exposure to the appearance of

What is Mad Cow Disease? Mad Cow Disease "is a normally extremely rare neurological disorder that affects the central nervous system of an animal and a human. The disease infested brain of the animal or human is slowly, progressively, and severely damaged. It has been categorized as a disease, which falls into the category of a disease known as Spongiform Encephalopathy. Having Bovine Spongiform Encephalopathy is an over-dramatized way of specifying that one has diseased brain tissue which is; spongy, porous, and no

The aggregation of prion proteins and their transmissibility from one cell to another has been shown to be evident (Cushman et al.; Goedert et al. 2010), therefore strongly suggesting that these events may play a role in pathogenesis for many diseases, including both AD and PD. While none of these diseases is infectious in an identical way as

In addition to the cervid species in which chronic waste disease can occur in wide variety of other animals. These other animals include monkeys, sheep, cattle, prairie voles, mice, and ferrets. Environmental transmission has been linked to contact with infected bodily fluids and tissues. Once the prions are in the environment chronic waste disease prions may remain infectious for many years. Thus, Decomposition of the disease carcasses, infected gut piles left by hunter, as well as urine, saliva, feces, and antler velvet of infected individuals that are deposited in the environment.

The Functions of Proteins Introduction Protein accounts for about three-fourths of the dry matter in human tissues other than fat and bone. It is a major structural component of hair, skin, nails, connective tissues, and body organs. It is required for practically every essential function in the body. Proteins are made from the following elements; carbon, hydrogen, oxygen, nitrogen and often sulphur and phosphorus.

Phenylketonuria, otherwise known as PKU, is a rare genetic disease that is caused by a person’s body being unable to metabolize the amino acid phenylalanine. The disease can cause mental retardation because the build up of phenylalanine in the body. When phenylalanine is not broken down and turned in a different amino acid, tyrosine, it can create other enzyme routes that build up in the blood stream and body tissue. This can be extremely harmful to the body and its development. This disease is caused by missing the enzyme phenylalanine hydroxylase, this enzyme is the one that normally breaks down phenylalanine. It is rare for this enzyme to be completely absence, but this form leads to the most severe mental

Transmissible spongiform encephalopathies (TSEs) are neurodegenerative diseases that are thought to be caused by the misfolding of prion proteins. Prions are able to replicate in the absence of nucleic acids. TSEs include: scrapie, bovine spongiform encephalopathy, Creutzfeldt-Jakob disease, kuru, Gerstmann-Straussler-Scheinker disease, and Fatal Familial Insomnia. They can affect many different animals, including humans. Currently, there are no ways to diagnose, treat, or cure TSEs, as much more research is needed before these diseases are completely understood.

Gerstmann-Sträussler-Scheinker disease (GSS) (Gerstmann et al., 1936) is a rare dominantly inherited prion prion (PrP) amyloidosis. GSS patients with a TTC to TCC DNA change at codon 198 of the prion protein (PRNP) gene resulting in a phenylalanine to serine substitution (F198S) in the prion protein from a large kindred in Indiana have been studied extensively by Ghetti, Farlow, and colleagues (Farlow et al., 1989; Ghetti et al., 1989; Dlouhy et al., 1992; Hsiao et al., 1992b; Ghetti et al., 1994; Ghetti et al., 1995; Unverzagt et al., 1997). Clinically, the F198S mutation carriers present with cerebellar ataxia, bradykinesia, rigidity, and dysarthria which may be preceded by psychiatric features including addiction, depression, or psychosis (Farlow et al., 1989). As the disease progresses, memory impairment and cognitive dysfunction becomes severe (Unverzagt et al., 1997). Neuropathologically, GSS F198S is characterized by deposition of plaques composed of PrP amyloid, as well as hyper-phosphorylated tau and neurofibrillary tangles (NFT) in the cerebral cortex and subcortical gray matter (Ghetti et al., 1989). Both GSS and

the ones that cause the well known “ mad cow ” disesase in Britain and “scrapie”