ABSTRACT
Approaches ..................................................................................................... 70 3.4 In uence of Habitat on Bacterial Diversity .................................................... 71 3.5 Cultivable versus Noncultivable Approach .....................................................77 3.6 Bacteria from Antarctica Involved in Hydrocarbon Degradation ..................77 3.7 Conclusions ..................................................................................................... 79 Acknowledgments .................................................................................................... 79 References ................................................................................................................ 79
The continent of Antarctica is considered to be one of the most extreme habitats in the world because it is the coldest, the driest (Claridge and Campbell, 1977; Vincent, 1988; Campbell and Claridge, 2000), the windiest, and the iciest of all known habitats with high solar (ultraviolet) radiation at least during the summer season (Smith et al., 1992). Despite the harsh climatic conditions, certain life forms such as mites, ticks, seals, penguins, mosses, lichens, bacteria, yeasts, and algae do exist in Antarctica (Cameron et al., 1970; Vishniac and Mainzer, 1972; Vincent, 1988; Wynn-Williams, 1990; Shivaji, 2005). Among these life forms, the cold-loving (psychrophilic) and cold-tolerant (psychrotrophic) bacteria are predominant and they play a key role in the Antarctic ecosystem, especially with respect to nutrient recycling (Stokes and Redmond, 1966; Delille and Lagarde, 1974; Herbert and Bell, 1974; Kelly et al., 1978; Tanner and Herbert, 1981; Tanner, 1985; Voytek and Ward, 1995; Cavanagh et al., 1996; Cavicchioli and Thomas, 2000; Chessa et al., 2000; Denner et al., 2001). Therefore, studies on the diversity, physiology, and molecular biology of
psychrophilic bacteria would provide important inputs on their distribution, survival strategies, and the molecular basis of their adaptation to low temperature. This chapter is essentially focused on the biodiversity of the bacteria of Antarctica.
