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MANGANESE RESISTANT BACTERIUM FROM POLLUTED WATER: SOME ENVIRONMENTAL FACTORS INFLUENCING CONJUGAL TRANSFER OF MN2+ -RESISTANT PLASMID
Authors: Anjum Nasim Sabri and Shahid Hasnain
Number of views: 280
A manganese resistant strain AnMn-1 was examined, which could prevent the toxic action of Mn2+ up to 2000 µg/ml in the medium. It was Gram-negative, pleomorphic, motile with high convex, undulate and circular colonies. It favoured neutral to alkaline media and was sensitive to Co2+, Hg2+, Cm and Sm but could tolerate Ni2+, Zn2+, Ba2+, Sn2+, Fe2+,Cu2+, Ap, Tc and Km in the medium. It was facultative anaerobic, spore-former and had catalase, oxidase and urease enzymes. It has the ability to produce acid from arabinose, rhamnose and glucose. It could hydrolyse urea, decarboxylase lysine and ornithine. Single plasmid was present in it. Conjugation experiments under different set of environmental conditions like time (0-24hrs), pH (6.5-8.5), temperature (25o, 28o, 32o, 37o) and donor to recipient ratio (1 to 10) revealed that maximum transfer frequency was found at 37oC when pH of the medium was 8 and also at donor to recipient ratio 10. It shared maximum characters with Gram-negative Bacillus.