Evaluation of Guanidium Thiocyanate as a Chemical Mutagen on the Expression of Nitrate Reductase Gene (NR) in Chlorella Sp., NTMP04

Nitrate is the predominant form of inorganic nitrogen utilized by higher plants, fungi and algae and its assimilation forms the major pathway for production of biologically useful nitrogen. Chlorella is a unicellular eukaryotic green alga, which offers a potentially useful system for the expression of hetrologous proteins. In the present study the microalgal samples were isolated from stagnant fresh water habitat (Tiruchirappalli, Tamil Nadu) and identified as Chlorella sp. NTMP04, Chlorella sp. NTMP05, Chlorella sp. NTMPO6. Chemical mutation was adopted using guanidine thiocyanate as mutagen and the mutants were assessed in the specific media such as SGII–NO and SGII–NH for nitrate reductase (NR) gene regulation. A strain Chlorella 3 4 sp, NTMPO4 was chosen for the biochemical and molecular analysis to confirm NR gene mutation. The genomic DNA has extracted from the wild and mutant strains and PCR amplification of NR gene was done using degenegarative primers (NR–F and NR–R). The wild type of Chlorella sp NTMP04 showed the presence of NR gene, whereas mutant did not amplified the specific gene. The comparative analysis showed the evidence of chemical based mutation in the Chlorella sp., NTMP04.