Peroxisomes are small organelles found in almost all eukaryotic cells that contain a variety of enzymes and are responsible for an assortment of essential metabolic processes (Wanders, 2013). Generally, these processes include the ? -oxidation of fatty acids and the detoxification of reactive oxygen and nitrogen species. In order for these reactions to occur, housekeeping functions are performed by peroxisomal proteins (Stanley & Williams, 2010). In general, peroxisomal proteins are important to the human body because they play a key role in peroxisome biogenisis and if the proteins misfolds this can lead to serious disorders.
Firstly, peroxisomal proteins are important to the human body because they play a vital role in peroxisome biogenesis. Peroxisome biogenesis consists of the formation of the peroxisomal membrane, import of proteins into the peroxisomal matrix and the proliferation of organelles (Eckert & Erdmann, 2003). The peroxisomal proteins that regulate peroxisome biogenesis are called peroxins. An important peroxin is Peroxin 5, also called Pex5p. This protein undergoes a cycle that involves: cargo recognition, membrane docking, cargo release and recycling (Stanley & Williams, 2010).
The cargo for Pex5p are proteins containing a peroxisome targeting signal one or PTS1 (Hawkins et al. , 2007). After binding to the PTS1, Pex5p brings the protein back to the peroxisome, deposits it and then goes back into the cytosol of the cell to repeat the cycle. This cycle allows the peroxisome to keep functioning (Stanley & Williams, 2010). The peroxisomes are important to a cell and peroxisomal proteins play an important role in keeping peroxisomes functioning. Secondly, there are many disorders and diseases that are caused by peroxisomal proteins misfolding.
If proteins do not fold properly, particularly peroxins, there can be serious peroxisomal biogenesis disorders similar to Zellweger Syndrome. Biogenesis disorders can impair brain, liver and kidney formation and functions. This all could be due to mutations in the protein such as amino acid substitutions or deletions (Stanley & Williams, 2010). Another biogenesis disease is primary hyperoxaluria type one. This disorder is caused by the misfolding of alanine-glyoxylate aminotransferase, commonly called AGT.
In this case, the mutated AGT still has the PTS1 but almost 90% of it is directed to mitochondria instead of the peroxisome (Erdmann, Schliebs & Wolf, 2010). This results in an increased amount of oxalate which causes chronic kidney disease (Cochat & Rumsby, 2013). The misfolding of peroxisomal proteins can lead to serious diseases and disorders that affect human health. Overall, peroxisomal proteins play an important role in the human body. These proteins execute vital functions in peroxisome biogenesis and the misfolding of the proteins can result in peroxisomal disorders.
In conclusion, the health of a human body depends on peroxisomal proteins and the important functions they perform. References Cochat, P. , & Rumsby, G. (2013). Primary hyperoxaluria. The New England Journal of Medicine, doi: 10. 1056/NEJMra1301564 Eckert, J. H. , & Erdmann, R. (2003). Peroxisome biogenesis. Reviews of Physiology, Biochemistry and Pharmacology, 147, 75-76. doi: 10. 1007/s10254-003-0007-z Erdmann, R. , Schliebs, W. , & Wolf, J. (2010). Peroxisomes as dynamic organelles: peroxisomal matrix protein import. FEBS Journal, 277(16), 3268–3278. doi: 10. 1111/j. 1742-4658. 2010.
07739. x Hawkins, J. , Mahony, D. , Maetschke, S. , Wakabayashi, M. , Teasdale, R. , & Boden, M. (2007). Identifying novel peroxisomal proteins. Proteins: Structure, Function, and Bioinformatics, 69(3), 606-616. doi: 10. 1002/prot. 21420 Stanley, W. A. , & Williams, C. P. (2010). Peroxin 5: A cycling receptor for protein translocation into peroxisomes. The International Journal of Biochemistry & Cell Biology, 42(11), 1771–1774. doi: 10. 1016/j. biocel. 2010. 07. 004 Wanders, R. A. (2013). Metabolic functions of peroxisomes in health and disease. doi: 10. 1016/j. biochi. 2013. 08. 022.