Nickel and Arsenite Responsive Proteomic Alterations in Cyanobacterium Anabaena PCC7120

Abstract

Ecological adaptation of organisms to environmental stresses including heavy metals denotes a novel example of evolution under extreme selection pressure. Cyanobacteria represent the largest and most diverse group of prokaryotes, capable of performing oxygenic photosynthesis and are frequently found in environments contaminated with heavy metals. Quite a lot of proteomic studies have investigated the effects of metals such as Cu, Co, Cd, and As(V) etc. on diazotrophic cyanobacteria. However, proteomic studies for the identification of proteins modulated Ni and arsenite [As(III)] have not been carried out. In the present work, we have analyzed the proteomic pattern alterations of the cyanobacterium Anabaena PCC7120 in response to Ni and As(III) in order to identify the metabolic processes affected by these metals. We found that some proteins are commonly regulated in response to the different metal, including ribulose1,5-bisphosphate carboxylase, chaperones and antioxidative defence proteins, whereas others such as specific efflux proteins, were specifically induced by each metal. Our results demonstrated that arsenite appears to be more toxic than nickel.

Calcium mediated nitric oxide responses: Acquisition of nickel stress tolerance in cyanobacterium Nostoc muscorum ATCC 27893

“…Nickel has been found to be more toxic in cyanobacteria causing distorted growth, pigment deterioration and arresting the excitation energy transfer in phycobilisomes in Nostoc muscorum [ 9 ]. Recently, Prajapati et al [ 10 ] have reported down regulation of several proteins along with of carbon metabolism and photosynthesis in Ni stressed Anabaena PCC 7120. The excess generation/accumulation of reactive oxygen species (ROS) causes damage to cellular membranes (lipids and proteins), enzymatic activities, reserve food (carbohydrates), genetic material (DNA) etc.…”