Songs of Love and Marriage in \u22Shijing Guofeng (詩經國風)\u22 and Ancient Courtship through Song and Dance

Anaerobic enrichment from sediments of hypersaline alkaline lakes in Wadi el Natrun(Egypt) with chitin resulted in the isolation of a fermentative haloalkaliphilic bacterium,strain ACht6-1, growing exclusively with insoluble chitin as the substrate in a sodiumcarbonate-based medium at pH 8.5–10.5 and total NaC concentrations from 0.4 to1.75 M. The isolate had a Gram-negative cell wall and formed lipid cysts in old cultures.The chitinolytic activity was associated with cells. Analysis of the 4.4 Mb draft genomeidentified pathways for chitin utilization, particularly, secreted chitinases linked to the cellsurface, as well as genes for the hydrolysis of other polysaccharides and fermentationof sugars, while the genes needed for aerobic and anaerobic respiration were absent.Adaptation to a haloalkaliphilic lifestyle was reflected by the gene repertoire encodingsodium rather than proton-dependent membrane-bound ion pumps, including the Rnftypecomplex, oxaloacetate decarboxylase, V-type ATPase, and pyrophosphatase. Thephylogenetic analysis using 16S rRNA gene and ribosomal proteins indicated thatACht6-1 forms a novel deep lineage at the class level within the bacterial candidatedivision TG3. Based on phylogenetic, phenotypic and genomic analyses, the novelchitinolytic bacterium is described as Chitinispirillum alkaliphilum gen. nov., sp. nov.

Genome analysis of <i>Chitinivibrio alkaliphilus</i> gen. nov., sp. nov., a novel extremely haloalkaliphilic anaerobic chitinolytic bacterium from the candidate phylum Termite Group 3

Anaerobic enrichments from hypersaline soda lakes with chitin as substrate yielded five closely related anaerobic haloalkaliphilic isolates growing on insoluble chitin by fermentation at pH10 and salinities up to 3.5M. The chitinolytic activity was exclusively cell associated. To better understand the biology and evolutionary history of this novel bacterial lineage, the genome of the type strain ACht1 was sequenced. Analysis of the 2.6Mb draft genome revealed enzymes of chitin-degradation pathways, including secreted cell-bound chitinases. The reconstructed central metabolism revealed pathways enabling the fermentation of polysaccharides, while it lacks the genes needed for aerobic or anaerobic respiration. The Rnf-type complex, oxaloacetate decarboxylase and sodium-transporting V-type adenosine triphosphatase were identified among putative membrane-bound ion pumps. According to 16S ribosomal RNA analysis, the isolates belong to the candidate phylum Termite Group 3, representing its first culturable members. Phylogenetic analysis using ribosomal proteins and taxonomic distribution analysis of the whole proteome supported a class-level classification of ACht1 most probably affiliated to the phylum Fibribacteres. Based on phylogenetic, phenotypic and genomic analyses, the novel bacteria are proposed to be classified as Chitinivibrio alkaliphilus gen. nov., sp. nov., within a novel class Chitinivibrione