Exploring the multiple biotechnological potential of halophilic microorganisms isolated from two Argentinean salterns.

The biodiversity and biotechnological potential of microbes from central Argentinean halophilic environments have been poorly explored. Salitral Negro and Colorada Grande salterns are neutral hypersaline basins exploded for NaCl extraction. As part of an ecological analysis of these environments, two bacterial and seven archaeal representatives were isolated, identified and examined for their biotechnological potential. The presence of hydrolases (proteases, amylases, lipases, cellulases and nucleases) and bioactive molecules (surfactants and antimicrobial compounds) was screened. While all the isolates exhibited at least one of the tested activities or biocompounds, the species belonging to Haloarcula genus were the most active, also producing antimicrobial compounds against their counterparts. In general, the biosurfactants were more effective against olive oil and aromatic compounds than detergents (SDS or Triton X-100). Our results demonstrate the broad spectrum of activities with biotechnological potential exhibited by the microorganisms inhabiting the Argentinean salterns and reinforce the importance of screening pristine extreme environments to discover interesting/novel bioactive molecules.

delta-Aminolevulinic acid dehydratase of Haloarcula argentinensis isolated from Tuz Lake in Turkey.

The delta-aminolevulinic acid dehydratase (ALAD) enzyme of a novel record for Turkish microbial flora was studied. The isolate I-113 was obtained from Tuz Lake in Turkey and identified as Haloarcula argentinensis. The ALAD enzyme of the isolate was assayed in order to determine its requirements and to be used as biomarker for lead pollution in it's ambient. In enzymic studies, the effects of various metals (Cd, Co, Mg, Mn, Ni, Pb, and Zn), pH (3-11), temperatures (25-55 degrees C), and salinity (15-25%) conditions have been examined. The data obtained from the studies were analyzed statistically by using Kruskal-Wallis, Mann-Whitney, correlation, regression, variance analysis, and significance tests were performed by using SPSS 10.0 for Windows. Although its optimum pH was determined as 7, it was still active at pH 3-11. The optimal temperature for the enzyme was observed to be 30 degrees C. Mn and Pb inhibited its activity significantly (p < 0.05) while Zn increased it slightly. The ALAD enzyme in H. argentinensis could be used as a biomarker for Pb contamination.