Potential Biotechnological Applications of Products from the Haloarchaeon Haloterrigena turkmenica

The extreme halophilic archaeon Haloterrigena turkmenica showed capacity of producing several classes of molecules of high interest in biotechnological fields. It was able to produce pigments and polyhydroxyalkanoates (PHA) when grown in selected growth conditions. In the present work, the microorganism was cultivated in halobacteria growth medium added with 1% (w v-1) glucose (HMG1), and in the same medium devoid of some components (nutrient deficient medium-NDMG1). Cells of H. turkmenica exhibited an orange colour when grown in HMG1, and after extraction with methanol, the membrane extract showed an absorption spectrum with the characteristic bell shape of yellow pigments. HPLC analysis allowed to identify astaxanthin among the pigments produced. Synthesis of PHA was followed in NDMG1 by optical microscopy with Nile Blue A, a dye which specifically bounds to poly-3-hydroxybutyrate (PHB). The biopolymer was proved to be produced during the stationary growth phase. These preliminary data show the high versatility of H. turkmenica in producing different valuable compounds when cultivated in defined growth medium conditions.