Haloarchaea Associated with Salt Crystals Obtained from Solar Salterns of Goa, India
FIG. 1. Haloarchaeal organisms entrapped in salt crystals obtained from solar salterns of Goa, India. Solar salt was obtained by evaporation of sea water in open pans. Orange-red colored salt revealed the occurrence of haloarchaeal organisms entrapped in the halite crystal (0.5 cm x 0.7 cm). The crystals were photographed using a Canon camera (Powershot A580, 4X zoom: 35(W) – 140 (T) mm).
FIG. 2. The scanning electron micrograph is of Haloferax, a haloarchaeal isolate. This isolate (ATCC BAA 644) was recovered from solar salterns of Ribandar, Goa, India and exhibits a cup-shaped or involuted morphology, characteristic of the genus Haloferax (1, 3).
Haloarchaea are microorganisms that grow at salinities between 20 and 30% NaCl concentration (2, 4). Salt pans, also known as solar salterns, are manmade large open pans where evaporation of sea water leads to formation of brine and then salt. This salt is then collected as heaps on the borders of the pans. Some of these salt pans show a characteristic orange-red coloration. Closer examination of the salt at the base of the heap revealed large crystals with orange-red centers as seen in Fig. 1.
The image clearly depicts microbial ecology. Organisms living in extreme conditions are known as extremophiles and dominant among them are the archaea. This visual can be used to demonstrate extremophilic microorganisms in their natural habitat thriving in saturating salt conditions. It can also be used for the comparative study of the two domains Archaea and Bacteria.
1. Mojica, F. J. M., F. Charbonnier, G. Juez, F. Rodríguez Valera, and P. Forterre. 1994. Effects of salt and temperature on plasmid topology in the halophilic archaeon Haloferax volcanii. J. Bacteriol. 176 :4966 – 4973.
2. Oren, A . 1994. The ecology of extremely halophilic archaea. FEMS Microbiol. Rev. 13 :415–439.
3. Rainey, F. A., and A. Oren (ed.). 2006. Extremophiles. Academic Press, St. Louis, MO.
4. Soppa, J. 2005. From replication to cultivation: hot news from haloarchaea. Curr. Opin. Microbiol. 8:737–744.