Asian Journal of Microbiology, Biotechnology & Environmental Sciences Paper

STUDY OF MEMBRANE FLUIDITY ON ACIDITHIOBACILLUS FERROOXIDANS GROWN IN INDIRECT (FERROUS SULPHATE AND SODIUM THIOSULPHATE) AND DIRECT (SULFUR) SUBSTRATES

R. MOHANA PRIYA, V.K. VAISHNAVI, T. NATHIYA, RAJNI KUMARI AND ANAND PREM RAJAN

Abstract

Precipitated in the culture container which explains the consumption of sodium thiosulphate by the organism (Beard et al., 2011). The sulfur compound in the sulfur substrate was oxidized by the enzyme tetrathionate hydrolase secreted by the organism A. ferrooxidans (Pablo et al., 2004).The organisms grown in 9k media shows variations in bioleaching of the metal, hence they can be measured by the membrane fluidity of the bacteria. The florescence dye used in the instrument was 1, 6 diphenyl 1, 3, 5 hexatriene (DPH). DPH enters the membrane with a simple saturable kinetics and, in the steady-state; it is localized in the hydrophobic core of the membrane. DPH not only resides in the plasma membrane but that it enters the cell and is incorporated into the membranes of the cellular organelles and into the intracellular lipid droplets. DPH fluorescence from the intracellular membranes and lipids is less polarized. Owing to this, the decrease of fluorescence anisotropy during the first 10-15 min of fluorescent labeling was observed and explained as resulting from the incorporation of DPH into the intracellular membranes and lipids (Bouchy et al.,1981). Furthermore, Hoeven et al., (1979), observed that some growth in DPH fluorescence intensity in transformed murine cells may persist even after the removal of the free probe from the suspending medium. The main objective is to measure membrane fluidity of A. ferrooxidans grown in indirect (ferrous sulphate and sodium thiosulphate) and direct (sulfur) substrates. The present work examines the result both in emission and excitation wavelength along with the adjustments made in the width length. The amplification at the fluorescence polarization is set at 1005 and 1040 V (Mykytczuk et al., 2010), the florescence dye used in the instrument is DPH dye which inserts the probe into the membrane to be examined for its fluidity and the data obtained are recorded in the FELIX software, which gives the result in peak graph, intensity in y-axis and wavelength in x -axis.