Moderately halophilic, alkalitolerant Halomonas campisalis MCM B-365 from Lonar Lake, India

Abstract

Seven bacterial isolates obtained from sediment and water samples, collected from the alkaline Lonar Lake were identified on the basis of their morphological, physiological and biochemical characteristics and were confirmed by 16S rDNA sequencing to be Halomonas campisalis. They were capable of using a variety of electron donors and were found to grow in the presence of sodium chloride (NaCl) up to 4 M, at pH from 7 to 11, 9 being the optimum. The isolates could grow over a wide range of temperatures (from 4 to 45°C) and showed temperature-dependent salt tolerance. They exhibited requirement of sodium for growth and could grow in any medium where NaCl is replaced by NaNO3 and Na2S2O3 but not in the presence of salts like LiCl, MgCl2·6H2O, KCl and NH4Cl. One of the seven isolates, ARI 351, was able to produce lipase at pH-9.0, while two isolates, ARI 351 and ARI 360, could accumulate polyhydroxyalkanoic acid (PHA) granules when grown in a medium containing maltose. Thus the H. campisalis isolated from Lonar Lake was different from the previously reported one, with respect to its biotechnological potential for production of Lipase and PHA. © 2007 Wiley-VCH Verlag GmbH & Co. KGaA.