Arpit Shukla1,2, Paritosh Parmar1, Dweipayan Goswami1, Baldev Patel1, Meenu Saraf3. 1. Department of Microbiology and Biotechnology, University School of Sciences, Gujarat University, Ahmedabad, Gujarat, 380009, India. 2. Department of Biological Sciences and Biotechnology, Indian Institute of Advanced Research (IIAR), Gandhinagar, Gujarat, 382426, India. 3. Department of Microbiology and Biotechnology, University School of Sciences, Gujarat University, Ahmedabad, Gujarat, 380009, India. msaraf@gujaratuniversity.ac.in.
Abstract
It is the acquisition of unique traits that adds to the enigma of microbial capabilities to carry out extraordinary processes. One such ecosystem is the soil exposed to radionuclides, in the vicinity of atomic power stations. With the aim to study thorium (Th) tolerance in the indigenous bacteria of such soil, the bacteria were isolated and screened for maximum thorium tolerance. Out of all, only one strain AM3, found to tolerate extraordinary levels of Th (1500 mg L-1), was identified to be belonging to genus Providencia and showed maximum genetic similarity with the type strain P. vermicola OP1T. This is the first report suggesting any bacteria to tolerate such high Th and we propose to term such microbes as 'thoriotolerant'. The medium composition for cultivating AM3 was optimized using response surface methodology (RSM) which also led to an improvement in its Th-tolerance capabilities by 23%. AM3 was found to be a good producer of EPS and hence one component study was also employed for its optimization. Moreover, the EPS produced by the strain showed interaction with Th, which was deduced by Fourier Transform Infrared (FTIR) spectroscopy.
It is the acquisin class="Chemical">tion of unique traits that adds to the enigma of microbial capabilities to carry out extraordinary processes. One such ecosystem is the soil exposed to radionuclides, in the vicinity of atomic power stations. Withthe aim to study thorium (Th) tolerance in the indigenous bacteria of such soil, the bacteria were isolated and screened for maximum thorium tolerance. Out of all, only one strain AM3, found to tolerate extraordinary levels of Th (1500 mg L-1), was identified to be belonging to genus Providencia and showed maximum genetic similarity withthe type strain P. vermicolaOP1T. This is the first report suggesting any bacteria to tolerate such high Th and we propose to term such microbes as 'thoriotolerant'. The medium composition for cultivating AM3 was optimized using response surface methodology (RSM) which also led to an improvement in its Th-tolerance capabilities by 23%. AM3 was found to be a good producer of EPS and hence one component study was also employed for its optimization. Moreover, the EPS produced by the strain showed interaction withTh, which was deduced by Fourier Transform Infrared (FTIR) spectroscopy.
Authors: C Tamponnet; A Martin-Garin; M-A Gonze; N Parekh; R Vallejo; T Sauras-Yera; J Casadesus; C Plassard; S Staunton; M Norden; R Avila; G Shaw Journal: J Environ Radioact Date: 2007-12-03 Impact factor: 2.674