Chitte et al., IJPSR, 2014; Vol. 5(12): 5250-5254. E-ISSN: 0975-8232; P-ISSN: 2320-5148 International Journal of Pharmaceutical Sciences and Research 5250 IJPSR (2014), Vol. 5, Issue 12 (Research Article) Received on 03 May, 2014; received in revised form, 22 August, 2014; accepted, 19 October, 2014; published 01 December, 2014 DETECTION AND ISOLATION OF RESTRICTION ENDONUCLEASE LIKE TOPOISOMERASE FROM THERMOPHILIC BACILLUS SUBTILUS STRAIN RC1 R.R. Chitte*, S.V. Deshmukh and P.P. Kanekar Microbial Sciences Division, MACS-Agharkar Research Institute, Pune 411 004, Maharashtra, India. ABSTRACT: Aims: Detection and isolation of restriction endonucleases like topoisomerase Thermophilic Bacillus subtilus strain RC1. Methods and results: Topoisomerase like enzyme activity is detected from thermophilc Bacilus sp. The isolated enzyme is partially characterized. The molecular weight of the enzyme is ~ 33 KDa and the optimum temperature for the activity is 37 0 C. The crude and gel purified enzyme activity were performed. The enzyme could be novel one, as the isolate is from hot water ecosystem. The restriction pattern of the new isolated enzyme is dissimilar to the commercially available enzymes. The enzyme retained the activity at a storage temperature of 4 0 C about one to two months. Magnesium chloride is found to be essential for the activity. The enzyme activity pattern is like topoisomrase. Activity is enhance in presence of ATP. The further characterization of topo like enzyme is in contined.Conclusion: The endonuclease type of topoisomerase enzyme is detected and isolated from thermophilic Bacillus sp. The restriction pattern studies indicate that the enzyme cuts standard plasmid DNA. Significant impact of the study: The restriction enzyme which is isolated from thermophilic Bacillus sp. and this microorganism was isolated from hot spring ecosystem. So enzyme might be new restriction endonuclease and there are few reports from thermophilic microorganisms. Restriction endonucleases with specific site of action will be useful in genetic engineering studies. INTRODUCTION: Nucleases are enzymes that break down nucleic acids into strands of DNA. 'Endo' or inside nucleases act at points along the strand and thus break DNA into short pieces. Endonucleases recognise a particular base sequence in DNA and cut the DNA. Some endonucleases cut the DNA at a specific point while others randomly split the DNA sequences. Specific endonucleases are used by genetic engineers who excise strands of DNA coded for a desirable genetic character. QUICK RESPONSE CODE DOI: 10.13040/IJPSR.0975-8232.5(12).5250-54 Article can be accessed online on: www.ijpsr.com DOI link: http://dx.doi.org/10.13040/IJPSR.0975-8232.5(12).5250-54 Endonucleases are classed as 'Restriction enzymes' since they are employed e.g. by bacteria to restrict infection by viruses (bacteriophages).The bacterial restriction enzyme attack the DNA of the infecting microorganisms. There are three distinct types of restriction endonucleases. Type I restriction endonucleases are complex endonucleases, and have recognition sequences of about 15 bp; they cleave the DNA about 1000 bp away from the 5' end of the sequence "TCA" located within the recognition site, e.g., EcoK, EcoB etc. Type II restriction endonucleases are remarkably stable and induce cleavage either, in most cases, within their recognition sequences or very close to them. More Keywords: Thermophilic, Bacillus sp, Topoisomerase etc Correspondence to Author: R. R. Chitte Scientist Microbial Sciences Division Agharkar Research Institute G.G. Agarkar Road, Pune - 411 004, Maharashtra, India E-mail: rrchitte10@rediffmail.com