Microbial diversity of soda lakes

Abstract

Soda lakes are highly alkaline extreme environments that form in closed drainage basins exposed to high evaporation rates. Because of the scarcity of Mg2+ and Ca2+ in the water chemistry, the lakes become enriched in CO3(2-) and Cl-, with pHs in the range 8 to > 12. Although there is a clear difference in prokaryotic communities between the hypersaline lakes where NaCl concentrations are > 15% w/v and more dilute waters, i.e., NaCl concentrations about 5% w/v, photosynthetic primary production appears to be the basis of all nutrient recycling. In both the aerobic and anaerobic microbial communities the major trophic groups responsible for cycling of carbon and sulfur have in general been identified. Systematic studies have shown that the microbes are alkaliphilic and many represent separate lineages within accepted taxa, while others show no strong relationship to known prokaryotes. Although alkaliphiles are widespread it seems probable that these organisms, especially those unique to the hypersaline lakes, evolved separately within an alkaline environment. Although present-day soda lakes are geologically quite recent, they have probably existed since archaean times, permitting the evolution of independent communities of alkaliphiles since an early period in the Earth's history.

Planktonic bacterial community composition of an extremely shallow soda pond during a phytoplankton bloom revealed by cultivation and molecular cloning

“…Phylogenetic diversity of bacterial communities inhabiting athalassohaline lakes around the world has been examined in detail from the end of the twentieth century (Duckworth et al 1996;Jones et al 1998). Recently, the cultivation dependent and independent analyses of planktonic and sediment microbial communities include, among others, studying the soda lakes of South-East Siberia, Russia (Foti et al 2007(Foti et al , 2008, North-East Mongolia (Sorokin et al 2004), Inner Mongolia, China (Zhang et al 2001;Ma et al 2004a), Lonar Lake, India (Wani et al 2006;Joshi et al 2008), the East African Rift Valley, Kenya and Tanzania (Rees et al 2004;Mwirichia et al 2010Mwirichia et al , 2011, Wadi An Natrun, Egypt (Mesbah et al 2007), as well as Mono Lake, California, USA (Hollibaugh et al 2001;Humayoun et al 2003) and Soap Lake, Washington, USA (Dimitru et al 2008).…”

“…Besides the oxygen-producing cyanobacteria, the dominant presence of sulfide in the water and the anoxic circumstances can provide favorable conditions for mass production of haloalkaliphilic phototrophic purple sulfur and non-sulfur bacteria, which may play a role in the development of the reddish-brown discoloration of these lakes (Jones et al 1998;Mesbah et al 2007;Milford et al 2000;Mwirichia et al 2011). …”

Bacterial diversity and activity along a salinity gradient in soda lakes of the Kulunda Steppe (Altai, Russia)

“…Few reviews (Zavarzin et al 1999;Jones et al 1998) summarize these results, showing that soda lakes contain representatives of the major trophic and phylogenetic groups of prokaryotes, and that they can be considered as autonomous systems, in which cycling of nutrients is close to complete. The most well-studied soda lakes are those located in the East African Rift Valley (Duckworth et al 1996;Rees et al 2004), in the Libyan desert (Wadi Natrun) (Imhoff et al 1979) and in North America, i.e.…”

Physiology and Molecular Phylogeny of Bacteria Isolated from Alkaline Distillery Lime

“…The few available reports concerning microbial diversity of alkaline environments indicate the existence of many physiological groups (Duckworth et al, 1996;Jones et al, 1998;Horikoshi, 1999;Ntougias et al, 2006;Felföldi et al, 2009). The aerobic microbial population of these ecosystems contains organotrophic bacteria, including members of the Bacillus species, which are able to produce a wide range of enzymes used for recycling biopolymers: proteases, lipases, amylases, and cellulases.…”

“…These microorganisms are source of several biotechnologically relevant enzymes and biomolecules, e.g. cellulases, amylases, and ectoine (Jones et al, 1998;Trotsenko and Khmelenina, 2002;Grant and Heaphy, 2010).…”