Biodegradation of 7-ketocholestrol (7-KC) by Thermobifidafusca IP1
By: Irum Perveen, Shama Sehar, Iffat Naz, Muhammad Asam Raza, Azim Jahangir Khan, Safia Ahmed
Key Words: Ketocholestrol, Oxysterol, Atherosclerosis, Age Related Macular Degeneration (AMD).
Int. J. Biosci. 8(4), 83-93, April 2016.
7-ketocholesterol (7KC), an oxidized derivative of cholesterol, has been implicated in a variety of chronic diseases including atherosclerosis, Alzheimer’s disease, Parkinson’s disease, cancer and age-related macular degeneration. It is formed by the autooxidation of cholesterol and especially cholesterol-fatty acid esters found in lipoprotein deposits, its elevated concentrations are associated with disruption of cellular homeostasis, decreased cell viability, and increased cell death.Enzymatic cleavage of 7-KC can serve as a key solution for the cure of a number of chronic diseases directly associated with its accumulation. A bacterial strain isolated from manure piles was characterized taxonomically and identified as Thermobifida fusca IP1 on the basis of amplification and sequencing of 16s rDNA. This isolate was tested for its ability to degrade 7-ketocholesterol in M9 liquid medium and showed to utilize 7-KC as the sole carbon and energy source. The degradation of 7-KC was hundred percent when tested in liquid culture. High Performance Liquid Chromatography (HPLC) analysis also showed complete removal of the compound from the sample after twelve days. This bacteriacan effectively be used to remove 7-KC and can lead to the development of a single potential therapeutic enzyme preparation to target a number of above mentioned chronic diseases related to 7-KC.