Biotechnological platforms of the moderate thermophiles, Geobacillus species: notable properties and genetic tools

The genus Geobacillus comprises gram-positive, moderate thermophilic, and aerobic or facultative anaerobic strains that can form endospores. The members of the genus are widely distributed in nature and have diverse habitats including cool environments. This is potentially due to not only their capacity for endospore formation but also their genetic plasticity that facilitates environmental adaptation, because Geobacillus spp. show remarkable genome diversification and have acquired beneficial properties that facilitate their exploitation of respective habitats. Such properties are often attractive for whole-cell applications performed at elevated temperatures. Consequently, extensive studies have been conducted to develop genetic tools for Geobacillus spp. and to generate their derivatives that are more practical for whole-cell applications. With the aim of highlighting the biotechnological platforms of Geobacillus spp., this chapter reviews genetic tools, notable properties, and biotechnological studies on Geobacillus spp. along with their history, habitats, and general characteristics. We also explore different perspectives from relevant studies.