Isolation and characterisation of bacteria from the haloalkaline Lake Elmenteita, Kenya

Abstract

Culture-independent studies show that soda lake environments harbour diverse groups of bacteria and archaea. In this study different enrichment and isolation media were used in an attempt to isolate novel groups of bacteria from Lake Elmenteita. Different media were prepared using filter-sterilised water from the lake. The isolates recovered were purified on tryptic soy agar supplemented with 1% sodium carbonate and 4% sodium chloride. Phylogenetic analysis of 181 partial 16S rRNA gene sequences with excellent quality showed that the majority of the isolates were affiliated to the class Gammaproteobacteria and to the genus Bacillus. Isolates from the genus Halomonas and Bacillus constituted 37 and 31% of the total sequenced isolates, respectively. Other groups recovered were related to Marinospirillum, Idiomarina, Vibrio, Enterococcus, Alkalimonas, Alkalibacterium, Amphibacillus, Marinilactibacillus and the actinobacteria Nocardiopsis and Streptomyces. Fifty-one different genera were represented with 31 and 15 cultures scoring with their nearest neighbour similarities below 98 and 97%, respectively. Some novel taxa were identified which had not been isolated previously from the soda environment. The results show that the use of different media with varying compositions can help retrieve novel bacterial diversity from the soda lake environment.

Diversity and ecological tolerance of bacteria isolated from the rhizosphere of halophyton plants living nearby Kiskunság soda ponds, Hungary

“…1), and were identifi ed as N. lucentensis and N. exhalans. The latter species was detected also by cultivation from the shallow haloalkaline Lake Elmenteita, Kenya [12].…”

“…The species of M. yunnanensis was recently described from surface-sterilized Polyspora axillaris roots [30]. Members of the genus Streptomyces are rarely isolated from soda lakes [12] but plant growth promoting activity of a Streptomyces isolate under saline soil conditions has been reported [31]. Representatives of the genus Nocardiopsis were isolated only from the rhizosphere of Bolboschoenus maritimus (Fig.…”

“…Members of different Halomonas species are also frequently isolated from soda lakes and soils [11][12][13][14][15][16]. In the rhizosphere of Bolboschoenus maritimus, strains identifi ed as species of haloalkaliphilic H. kenyensis described from sediment samples of Kenyan soda lakes [32] and alkalitolerant and moderately halophilic H. boliviensis [33] described from a soil sample around the hypersaline lake Laguna Colorada (Bolivia) were found (Fig.…”

“…1). Representatives of Bacillus species are frequently isolated from different soda lakes and soils worldwide [10][11][12][13][14][15][16] [24] and B. alkalisediminis [25] described from the sediment of Kiskunság soda ponds were recovered (Fig. 1).…”

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

“…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).…”