Extremely Halophilic Biohydrogen Producing Microbial Communities from High-Salinity Soil and Salt Evaporation Pond

Extreme halophiles offer the advantage to save on the costs of sterilization and water for biohydrogen production from lignocellulosic waste after the pretreatment process with their ability to withstand extreme salt concentrations. This study identifies the dominant hydrogen-producing genera and species among the acclimatized, extremely halotolerant microbial communities taken from two salt-damaged soil locations in Khon Kaen and one location from the salt evaporation pond in Samut Sakhon, Thailand. The microbial communities’ V3–V4 regions of 16srRNA were analyzed using high-throughput amplicon sequencing. A total of 345 operational taxonomic units were obtained and the high-throughput sequencing confirmed that Firmicutes was the dominant phyla of the three communities. Halanaerobium fermentans and Halanaerobacter lacunarum were the dominant hydrogen-producing species of the communities. Spatial proximity was not found to be a determining factor for similarities between these extremely halophilic microbial communities. Through the study of the microbial communities, strategies can be developed to increase biohydrogen molar yield.

Halamphora siqueirosii (Bacillariophyta), a new diatom species isolated from a hypersaline evaporation pond in Baja California Peninsula, Mexico

Halamphora siqueirosii sp. nov. is a marine benthic diatom isolated as a monoclonal culture from a hypersaline evaporation pond at the Guerrero Negro Saltworks, Baja California Sur, Mexico. Analysis of the valve ultrastructure of this taxon using light and electron microscopy indicated that its uniseriate striae and the density of its dorsal striae are useful characteristics for discriminating H. siqueirosii from other species with similar morphological patterns. The phylogenetic analyses performed with nuclear ribosomal genes, the small (18S) and large subunits (28S), and chloroplast gene ribulose-bisphosphate carboxylase (rbcL) fragments showed that H. siqueirosii is closely related to H. americana, H. calidilacuna and H. incelebrata. Morphological differences between this new species and similar ones are discussed.

Complete Genome Sequence of Halocella sp. Strain SP3-1, an Extremely Halophilic, Glycoside Hydrolase- and Bacteriocin-Producing Bacterium Isolated from a Salt Evaporation Pond

Halocella sp. strain SP3-1, a cellulose-degrading bacterium, was isolated from a hypersaline evaporation pond in Thailand.