Salty Twins: Salt-Tolerance of Terrestrial Cyanocohniella Strains (Cyanobacteria) and Description of C. rudolphia sp. nov. Point towards a Marine Origin of the Genus and Terrestrial Long Distance Dispersal Patterns

Albertania and Egbenema gen. nov. from Nigeria and the United States, expanding biodiversity in the Oculatellaceae (cyanobacteria)

Knowledge of the tropical terrestrial cyanobacterial flora from the African continent is still limited. Of 31 strains isolated from soil and subaerial samples collected in Lagos State, Nigeria, three were found to be in the Oculatellaceae, including two species in a new genus. Subsequently, isolates from microbial mats in White Sands National Park in New Mexico, United States, and from a rock near the ocean in Puerto Rico, United States, were found to belong to the new genus as well. Cyanobacterial isolates were characterized microscopically, sequenced for the 16S rRNA gene and associated ITS region, and phylogenetically analyzed. Egbenema gen. nov., with three new species, as well as two new species of Albertania were differentiated from all other Oculatellaceae. Both genera belong to a supported clade within the Oculatellaceae that includes Trichotorquatus and Komarkovaea. The two new species of Albertania, A. egbensis and A. latericola, were from the same sample, but were evolutionarily separate based on 16S rRNA gene phylogenies, percent identity below the 98.7% threshold, and ITS rRNA percent dissimilarity >7.0%. Egbenema aeruginosum gen. et sp. nov. was phylogenetically separated from Trichotorquatus and Albertania but was in a clade with other strains belonging to Egbenema. The two Egbenema strains from the United States are here named Egbenema epilithicum sp. nov. and Egbenema gypsiphilum sp. nov. Our results support the hypothesis that further species discoveries of novel cyanobacteria will likely be made in soils and subaerial habitats, as these habitats continue to be studied, both in tropical and temperate biomes.

Trichotorquatus salinus sp. nov. (Oculatellaceae, Cyanobacteria) from a Saltern of Gomso, Republic of Korea

Six strains of subaerial cyanobacteria were isolated from a Gomso saltern in the Republic of Korea, all of which were studied using morphological and molecular traits. Trichotorquatus salinus sp. nov. was studied using a light microscope (LM), transmission electron microscope (TEM), 16S rRNA, 16S–23S ITS region, and ecological data. T. salinus is a thin and simple filament with a false branch and a firm collar sheath. The phylogenetic analyses of 16S rRNA revealed that Trichotorquatus formed a monophyletic lineage and the strains of T. salinus formed a distinct clade among the species in the genus Trichotorquatus. In the statistical analysis, the inter-species genetic distance of the five species of Trichotorquatus, including T. salinus, is shown to be greater than the distance of the previously reported species of Trichotorquatus. Additionally, 16S–23S ITS gene sequences between T. salinus and four species of Trichotorquatus showed dissimilarities of 55.3–59.4%. In the secondary structure of 16S–23S ITS region (type 2 operon), D1–D1′, Box-B, and V3 helix of T. salinus were different from the other taxa in the genus Trichotorquatus. These results demonstrate that T. salinus sp. nov. has unique morphological, ecological, and molecular traits. Therefore, we propose that T. salinus sp. nov. is a novel species belonging to the genus Trichotorquatus.

Metagenome-Assembled Genome of Cyanocohniella sp. LLY from the Cyanosphere of Llayta, an Edible Andean Cyanobacterial Macrocolony

Cyanobacterial macrocolonies known as Llayta are found in Andean wetlands and have been consumed since pre-Columbian times in South America. Macrocolonies of filamentous cyanobacteria are niches for colonization by other microorganisms. However, the microbiome of edible Llayta has not been explored. Based on a culture-independent approach, we report the presence, identification, and metagenomic genome reconstruction of Cyanocohniella sp. LLY associated to Llayta trichomes. The assembled genome of strain LLY is now available for further inquiries and may be instrumental for taxonomic advances concerning this genus. All known members of the Cyanocohniella genus have been isolated from salty European habitats. A biogeographic gap for the Cyanocohniella genus is partially filled by the existence of strain LLY in Andes Mountains wetlands in South America as a new habitat. This is the first genome available for members of this genus. Genes involved in primary and secondary metabolism are described, providing new insights regarding the putative metabolic capabilities of Cyanocohniella sp. LLY.