TITLE:
Differential Proteome Analysis of Chlamydomonas reinhardtii Response to Arsenic Exposure
AUTHORS:
Chamari Walliwalagedara, Harry Keulen, Belinda Willard, Robert Wei
KEYWORDS:
Arsenic Stress; Chlamydomonas reinhardtii; Heavy Metal; Oxygen Stress; Proteomics; 2-DE Mass Spectrometry
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.3 No.6,
June
21,
2012
ABSTRACT: The fresh water unicellular green alga Chlamydomonas reinhardtii was used to explore whether it could function as a model system to identify proteins that are differentially expressed in response to arsenate exposure. Cells were treated with different concentrations of arsenate ranging from 100 - 400 μM. When exposed to 200 μM arsenate, the amount of live cells started to lessen on the second day and continued to diminish, indicating a toxic effect of arsenate. Proteomic analysis was used to investigate if these cells showed a specific response to arsenic-induced stress. Fifteen proteins were found that were over-expressed in the 200 μM arsenate-treated samples and two proteins were found to be very strongly over-expressed in samples treated with 400 μM. These were selected for identification using liquid chromatography coupled with tandem mass spectrometry. Oxidative stress and protein damage were the major effects as shown by the up-regulation of Mn-superoxide dismutase, an oxygen-evolving enhancer protein, a chaperonin-like protein and a heat shock protein.