Bruguierivorax albus gen. nov. sp. nov. Isolated from Mangrove Sediment and Proposal of Bruguierivoracaceae fam. nov

Description of a new genus of the Pectobacteriaceae family isolated from water in coastal brackish wetlands of the French Camargue region, Prodigiosinella gen. nov., including the new species Prodigiosinella aquatilis sp. nov

The Pectobacteriaceae family comprises plant pathogens able to provoke diverse diseases, including plant maceration due to the production of pectinases disrupting the plant cell wall. To better understand their diversity, a survey of pectinolytic bacteria was performed in brackish lakes of the French region La Camargue near the Mediterranean Sea. The genome of six atypical isolates was sequenced; their size is around 4.8 to 5.0 Mb, including a plasmid of 59 to 61 kb; their G+C values range from 49.1 to 49.3 mol%. Phylogenetic analyses indicated that the novel strains form a new clade of Pectobacteriaceae that branches at the basis of the group encompassing the genera Lonsdalea, Musicola, and Dickeya. Based on phenotypic, genomic and phylogenetic characteristics, we propose the creation of a new genus with the name Prodigiosinella gen. nov. Both the phenotypic and phylogenetic analyses separated the strains into two distinct subgroups, G1 and G2. The type strain LS101T (CFBP 8826T = LMG 32072T) and strain CE70 (CFBP 9054 = LMG 32867) are representative G1 and G2 members, respectively. Three genomic methods were used to analyze DNA-DNA relatedness: digital DNA-DNA hybridization (isDDH), average nucleotide identity (ANI), and genome alignment fraction (AF). They revealed a close relationship between genomes of the two groups, supporting their appurtenance to a same species for which we propose the name Prodigiosinella aquatilis sp. nov. Four strains previously designated as Serratia sp. (ATCC 39006), Brenneria "ulupoensis" (K61) or Erwinia sp. (MK01 and MK09) belong to the new genus Prodigiosinella.

Sodalis ligni Strain 159R Isolated from an Anaerobic Lignin-Degrading Consortium

Novel bacterial isolates with the capabilities of lignin depolymerization, catabolism, or both, could be pertinent to lignocellulosic biofuel applications. In this study, we aimed to identify anaerobic bacteria that could address the economic challenges faced with microbial-mediated biotechnologies, such as the need for aeration and mixing. Using a consortium seeded from temperate forest soil and enriched under anoxic conditions with organosolv lignin as the sole carbon source, we successfully isolated a novel bacterium, designated 159R. Based on the 16S rRNA gene, the isolate belongs to the genus Sodalis in the family Bruguierivoracaceae. Whole-genome sequencing revealed a genome size of 6.38 Mbp and a GC content of 55 mol%. To resolve the phylogenetic position of 159R, its phylogeny was reconstructed using (i) 16S rRNA genes of its closest relatives, (ii) multilocus sequence analysis (MLSA) of 100 genes, (iii) 49 clusters of orthologous groups (COG) domains, and (iv) 400 conserved proteins. Isolate 159R was closely related to the deadwood associated Sodalis guild rather than the tsetse fly and other insect endosymbiont guilds. Estimated genome-sequence-based digital DNA-DNA hybridization (dDDH), genome percentage of conserved proteins (POCP), and an alignment analysis between 159R and the Sodalis clade species further supported that isolate 159R was part of the Sodalis genus and a strain of Sodalis ligni. We proposed the name Sodalis ligni str. 159R (=DSM 110549 = ATCC TSD-177). IMPORTANCE Currently, in the paper industry, paper mill pulping relies on unsustainable and costly processes to remove lignin from lignocellulosic material. A greener approach is biopulping, which uses microbes and their enzymes to break down lignin. However, there are limitations to biopulping that prevent it from outcompeting other pulping processes, such as requiring constant aeration and mixing. Anaerobic bacteria are a promising alternative source for consolidated depolymerization of lignin and its conversion to valuable by-products. We presented Sodalis ligni str. 159R and its characteristics as another example of potential mechanisms that can be developed for lignocellulosic applications.