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International audience; Two bacterial strains were isolated and identified using microbial culturomics and characterised according to the taxono-genomics strategy. The strictly anaerobic strain, Marseille-P3773(T), forms smooth and translucent colonies consisting of Gram-stain negative, non-motile and non-spore-forming rod-shaped cells. Strain Marseille-P3787(T) consists of Gram-stain positive, motile and spore-forming cells resulting in grey and translucent colonies. The phylogenetic analysis of the 16S rRNA gene of strains Marseille-P3773(T) and Marseille-P3787(T) revealed a 96.9% similarity level with Lachnotalea glycerini strain DLD10 and 97% identity with Paenibacillus uliginis strain N3/975, respectively. The genome of strain Marseille-P3773 is 4,260,534 bp long with a 40.3 mol% G + C content and includes 3879 predicted genes of which 3769 are protein-coding genes, 76 RNAs and 34 are pseudo-genes. Strain Marseille-P3787 had a genome size of 4,833,032 bp with a 47.9 mol% G + C and has 4481 predicted genes of which 4265 are protein-coding genes, 101 RNAs and 115 are pseudo-genes. According to the data collected on these strains and, more specifically to the genomic comparison, we suggest the creation of a new genus and species, Konateibacter massiliensis gen. nov., sp. nov. with strain Marseille-P3773(T) (=CSURP3773 and CCUG71331) as its type strain within the Lachnospiraceae family, as well as a new species, Paenibacillus faecalis sp. nov. with strain Marseille-P3787(T) (=CSURP3787 and CCUG71650) as its type strain within the Paenibacillus genus.

We describe a new multidrug resistant Chitinophaga species that was isolated from patients with type 2 diabetes in Vietnam. Strain BD 01T was cultivated in 2017 from a blood sample of a patient suffering from bacteremia. Strain VP 7442 was isolated in 2018 from a pleural fluid sample of a patient who had presented with lung abscess and pleural effusion. Both strains are aerobic, Gram-negative, non-motile and non-spore-forming. The 16S rRNA gene sequences of both strains are 100 % similar and share a highest 16S sequence identity with Chitinophaga polysaccharea MRP-15T of 97.42 %. Their predominant fatty acid is iso-C15 : 0 (73.8 % for strain BD 01T and 79.8 % for strain VP 7442). The draft genome sizes of strains BD 01T and VP 7442 are 6 308 408 and 6 308 579 bp, respectively. They are resistant to beta-lactams, aminoglycosides, fluoroquinolones, metronidazole, fosfomycin, vancomycin and macrolides, and exhibit 20 and 18 antimicrobial resistance-related genes, respectively. Using the multiphasic taxonogenomic approach, we propose that strains BD 01T (=CSUR P9622=VTCC 70981) and VP 7442 (=CSUR P9623=VTCC 70982) represent a new species, for which we propose the name Chitinophaga vietnamensis sp. nov. Strain BD 01T was chosen as type strain of C. vietnamensis sp. nov.

Kwashiorkor and marasmus are two clinical syndromes observed in severe acute malnutrition. In this review, we highlighted the differences between these two syndromes by reviewing the data comparing kwashiorkor and marasmus in literature, combined with recent microbiological findings and meta-analysis. Depletion of antioxidants, vitamins and minerals were more severe in kwashiorkor than marasmus. This was consistent with the severe and uncontrolled oxidative stress associated with the depletion of gut anaerobes and the relative proliferation of aerotolerant gut pathogens. This relative proliferation and invasion of gut microbes belonging to the aerotolerant Proteobacteria phylum and pathogens suggested a specific microbial process critical in the pathogenesis of kwashiorkor. Liver mitochondrial and peroxisomal dysfunction could be secondary to toxic microbial compounds produced in the gut such as ethanol, lipopolysaccharides and endotoxins produced by Proteobacteria, particularly Klebsiella pneumoniae, and aflatoxin produced by Aspergillus species. The gut-liver axis alteration is characterized by oedema and a fatty and enlarged liver and was associated with a dramatic depletion of methionine and glutathione, an excessive level of free circulating iron and frequent lethal bacteraemia by enteric pathogens. This was consistent with the fact that antibiotics improved survival only in children with kwashiorkor but not marasmus. The specific pathogenic characteristics of kwashiorkor identified in this review open new avenues to develop more targeted and effective treatments for both marasmus and/or kwashiorkor. Urgent correction of plasma glutathione depletion, alongside supply of specific essential amino acids, particularly methionine and cysteine, early detection of pathogens and an antibiotic more efficient than amoxicillin in supressing gut Proteobacteria including K. pneumoniae, and probiotics to restore the human gut anaerobic mature microbiota could save many more children with kwashiorkor.