Oral Presentation Australian Society for Microbiology Annual Scientific Meeting 2017

Isolation and characterization of Akkermansia muciniphila strain NM-1 (#158)

Nida Murtaza 1 , Páraic Dr. Ó Cuív 1 , Mark Prof. Morrison 1
  1. Diamantina Institute, Faculty of Medicine, UNIVERSITY OF QUEENSLAND, Brisbane, QLD, Australia

The human gut is coated with mucins that separate the epithelial layer from the digesta and microbes present in the lumen, thereby acting as a physical barrier and defence against pathogenic microbes and other insults. The mucus layer can also act as a nutrient source for various mucosa-associated bacteria, such as Akkermansia muciniphila. Despite the relatively recent identification of Akkermansia spp. as a member of the gut microbiome, there is a growing interest in how the bacterium might affect human health via anti-obesogenic and anti-inflammatory properties; however, the isolates and strains available for functional and comparative studies are scant. Here, we describe the isolation and characterisation of a new strain of A. muciniphila, NM-1, isolated from a faecal sample of a healthy adult volunteer. An axenic culture of A. muciniphila NM-1 was produced using a mucin-enrichment medium combined with antibiotic selection.  Gram staining, cell morphology, and 16S rRNA gene amplicon sequencing were used to confirm the taxonomic assignment of strain NM-1 as A. muciniphila. The NM-1 genome was sequenced using Illumina technology and the post assembly alignment with the A. muciniphila MucT genome revealed a high degree of synteny and co-linearity between the two strains. However, the NM-1 genome does appear to be larger at 2.937 Mbp and with 2818 predicted coding sequences; compared to 2.665 Mbp and 2323 predicted coding sequences for strain MucT. Of particular note is that strain NM-1 appears to possess a greater number of genes than the type strain that encode for the utilization of N-acetylglucosamine and related aminosugars, mobile genetic elements, and  “hypothetical” proteins. Interestingly, although there is no direct evidence for growth with prebiotic oligo- and polysaccharides, both strains possess genes encoding putative functions involved with fructose and mannose utilization. Such findings suggest that the metabolic capacity of Akkermansia spp. extend to these monomeric carbohydrates but is contingent upon their release from more complex “fibres” by other members of the gut microbiome.