Prions
| Line 22: | Line 22: | ||
examples of prion disease: | examples of prion disease: | ||
| − | *[[Scrapie|scrapie]] | + | *[[Scrapie|scrapie]] - in sheep |
*[[Bovie spongiform encephalopathy|Bovie spongiform encephalopathy]] (BSE) [[Mad cow disease|mad cow disease]] | *[[Bovie spongiform encephalopathy|Bovie spongiform encephalopathy]] (BSE) [[Mad cow disease|mad cow disease]] | ||
*[[Kuru|Kuru]] (transmitted by ritual cannibalism) | *[[Kuru|Kuru]] (transmitted by ritual cannibalism) | ||
*[https://teaching.ncl.ac.uk/bms/wiki/index.php/Creutzfeldt%E2%80%93Jakob_disease_(CJD) Creutzfeldt–Jakob disease (CJD)] | *[https://teaching.ncl.ac.uk/bms/wiki/index.php/Creutzfeldt%E2%80%93Jakob_disease_(CJD) Creutzfeldt–Jakob disease (CJD)] | ||
| − | *Chronic Wasting Disease (CWD) | + | *Chronic Wasting Disease (CWD) - in deer and elk |
=== References === | === References === | ||
<references /> | <references /> | ||
Revision as of 13:01, 25 November 2018
Not all infectious diseases are transmitted by bacteria or viruses. Some neurological diseases, such as Creutzfeldt-Jakob disease (CJD) or mad cow disease is in fact caused by agents called Prions, which are of similar size to viruses but are made up of only protein[1]. These diseases are can be called Prion diseases or transmissible spongiform encephalpathies (TSE)[2].
Prions have these characteristics:
- "The transmissible agent consists of aggregated forms of a specific protein"[3].
- These protein aggregates cannot be degraded by the agents that degrade most other proteins[4].
- "The protein is largely or completely derived from a cellular protein called PrP, that is normally present in the brain"[5].
So an aggregated form of a protein (that is already present in the brain) is the infectious agent in prion diseases[6].
The pathologic mechanism of prions is often associated with structural change. Exogenous prions cause the endogenous host proteins to undergo a structural change, rendering them functionless or harmful.
Prions size and structure enable them to resistance to:
- proteases
- heat (not in 100 celsius)
- radiation
- fixative treatments (formaldehyde)
If only the secondary, tertiary and quaternary structure destroys the prion can fold back to the prion after the influence of the substance
examples of prion disease:
- scrapie - in sheep
- Bovie spongiform encephalopathy (BSE) mad cow disease
- Kuru (transmitted by ritual cannibalism)
- Creutzfeldt–Jakob disease (CJD)
- Chronic Wasting Disease (CWD) - in deer and elk
References
- ↑ J. M. Berg et al. (2007) p 53, Biochemistry, Sixth edition, New York, W.H. Freeman and Company
- ↑ http://www.who.int/bloodproducts/tse/en/
- ↑ J. M. Berg et al. (2007) p 53, Biochemistry, Sixth edition, New York, W.H. Freeman and Company
- ↑ J. M. Berg et al. (2007) p 53, Biochemistry, Sixth edition, New York, W.H. Freeman and Company
- ↑ J. M. Berg et al. (2007) p 53, Biochemistry, Sixth edition, New York, W.H. Freeman and Company
- ↑ J. M. Berg et al. (2007) p 54, Biochemistry, Sixth edition, New York, W.H. Freeman and Company
