Prokaryotic Diversity in Aran-Bidgol Salt Lake, the Largest Hypersaline Playa in Iran

Abstract

Prokaryotic diversity in Aran-Bidgol salt lake, a thalasohaline lake in Iran, was studied by fluorescence in situ hybridization (FISH), cultivation techniques, denaturing gradient gel electrophoresis (DGGE) of PCR-amplified fragments of 16S rRNA genes and 16S rRNA gene clone library analysis. Viable counts obtained (2.5–4 × 106 cells mL−1) were similar to total cell abundance in the lake determined by DAPI direct count (3–4×107 cells mL−1). The proportion of Bacteria to Archaea in the community detectable by FISH was unexpectedly high and ranged between 1:3 and 1:2. We analyzed 101 archaeal isolates and found that most belonged to the genera Halorubrum (55%) and Haloarcula (18%). Eleven bacterial isolates obtained in pure culture were affiliated with the genera Salinibacter (18.7%), Salicola (18.7%) and Rhodovibrio (35.3%). Analysis of inserts of 100 clones from the eight 16S rRNA clone libraries constructed revealed 37 OTUs. The majority (63%) of these sequences were not related to any previously identified taxa. Within this sampling effort we most frequently retrieved phylotypes related to Halorhabdus (16% of archaeal sequences obtained) and Salinibacter (36% of bacterial sequences obtained). Other prokaryotic groups that were abundant included representatives of Haloquadratum, the anaerobic genera Halanaerobium and Halocella, purple sulfur bacteria of the genus Halorhodospira and Cyanobacteria.

Limnology and plankton diversity of salt lakes from Transylvanian Basin (Romania): A review

“…as most frequently encountered genera were retrieved both by culture and molecular approaches , 2015Andrei et al, 2015Andrei et al, , 2017a. the culturable diversity of aerobic haloarchaea reported in the saline transylvanian lakes exceeded that reported for other inland hypersaline habitats in turkey, iran, and spain (Özcan et al, 2007;Makhdoumi-Kakhki et al, 2012;luque et al, 2012). the most hypersaline lake brâncoveanu (>20% salinity starting from surface) was found to harbor the highest diversity of archaeal community possibly including the recently described Halanaerorchaeum sulfurireducens with the unusual anaerobic s 0 -reducing metabolism (sorokin et al, 2016).…”

“…According to the above classifications, all inland salt lakes in transylvanian basin (central romania) are pH-neutral, athalassohaline systems (baricz et al, 2014; 2015). on the contrast to numerous neutral salt lakes investigated to date in north America (belovsky et al, 2011), Middle east (Makhdoumi-Kakhki et al, 2012;oren, 2016), Australia (Podell et al, 2013) or Antarctica (laybournLimnology and plankton diversity of salt lakes from Transylvanian Basin (Romania): A review Parry and bell, 2014), the limnology and biology of salt lakes in romania are only scarcely visible in the main stream of scientific literature. Previous works reported on morphometry and limnogeology (bulgăreanu (1993; 1996), zoo-and phytoplankton diversity (ionescu et al, 1998), enzymatic activity associated to organic-rich sediments (Muntean et al, 1996) and potential for novel microbial taxa in romanian salt lakes (enache et al, 2007).…”

Comparison of Bacterial Biodiversity and Enzyme Production in Three Hypersaline Lakes; Urmia, Howz-Soltan and Aran-Bidgol

“…The depth of salt layer which covers almost all the surface of the playa varies from 5 to 54 m, its pH is neutral (about 7.0-7.5) and its salinity reaches saturation. Most salts in this lake are NaCl, Na 2 SO 4 , MgCl 2 and MgSO 4 with traces of carbonate ions [3,4].…”

“…Carboxy methyl cellulase activity of the cultures was screened in a solid medium containing (g/L): yeast extract 0.5, glucose 1, agar 17, carboxy methyl cellulose 5, NaNO 3 1, K 2 HPO 4 2, KCl 1, MgSO 4 0.5. After incubation at 34°C for 7 days, the plates were flooded with 0.1 % congo red solution.…”

“…Lakes with salt composition similar to seawater that named thalassohaline and athalassohaline lakes originated from evaporation of inland surface water which can differ in their ion composition compared with seawater derived lakes [1]. Iran possesses various hypersaline environments including permanent hypersaline lakes such as Urmia Lake and seasonal hypersaline lakes (playa) such as Aran-Bidgol and Howz-Soltan, which the microbial diversity of them has been little studied [2][3][4], that causes their potential usage in biotechnology remains unknown.…”