The nasal mutualist Dolosigranulum pigrum AMBR11 supports homeostasis via multiple mechanisms

Abstract

Summary Comparing the nasal microbiome of healthy individuals and chronic rhinosinusitis (CRS) patients revealed Dolosigranulum pigrum as a species clearly associated with nasal health, although isolates obtained from healthy individuals are scarce. In this study, we explored the properties of this understudied lactic acid bacterium by integrating comparative genomics, habitat mining, cultivation, and functional characterization of interaction capacities. Mining 10.000 samples from the Earth Microbiome Project of 17 habitat types revealed that Dolosigranulum is mainly associated with the human nasal cavity. D. pigrum AMBR11 isolated from the nose of a healthy individual exerted antimicrobial activity against Staphylococcus aureus , decreased proinflammatory cytokine production in airway epithelial cells, and Galleria mellonella larvae mortality induced by this important nasal pathobiont. Furthermore, the strain protected the nasal barrier function in a mouse model using interleukin-4 as disruptive cytokine. Hence, D. pigrum AMBR11 is a mutualist with high potential as topical live biotherapeutic product.

Sex differences in the nasal microbiome of healthy young adults

“…Notably, Staphylococcus aureus, a commonly known opportunistic pathogen in the nasal cavity, was not only more prevalent but also significantly more enriched in females. Meanwhile, Corynebacterium accolens, Corynebacterium pseudodiphtheriticum, and Dolosigranulum pigrum, for which cooperative or competitive relationships with S. aureus have been identified in former studies via association and experimental validation (Brugger et al, 2020;De Boeck et al, 2021;Krismer et al, 2017;Yan et al, 2013), as the most abundant species among others in this cohort, were also significantly more abundant in females. Additionally, Lactobacillus spp., typically found in the female vagina, has been recently reported to have a niche in the human nose and may exert a beneficial effect (De Boeck et al, 2020).…”

“…The nasal cavity is featured by limited nutrients and adhesion surfaces (Krismer et al, 2014), and represents a major reservoir for opportunistic pathogens, such as Staphylococcus aureus, Streptococcus pneumoniae , and Haemophilus influenzae (Clark, 2020). The microbes in this niche are hence in constant competition, and sometimes form cooperative relation, to gain self-fitness (Brugger et al, 2020; De Boeck et al, 2021; Zipperer et al, 2016). Extensive antimicrobial substance productions have been identified in nasal microbes, which can be potential mediators of the interactions (De Boeck et al, 2021; Donia et al, 2014; Donia and Fischbach, 2015; Iwase et al, 2010; Janek et al, 2016; Zipperer et al, 2016).…”

“…The microbes in this niche are hence in constant competition, and sometimes form cooperative relation, to gain self-fitness (Brugger et al, 2020; De Boeck et al, 2021; Zipperer et al, 2016). Extensive antimicrobial substance productions have been identified in nasal microbes, which can be potential mediators of the interactions (De Boeck et al, 2021; Donia et al, 2014; Donia and Fischbach, 2015; Iwase et al, 2010; Janek et al, 2016; Zipperer et al, 2016). The competitive (antagonistic) and cooperative (synergistic) interactions influence both the initial colonization of pathogens and the thereafter dynamics.…”

Spontaneous Riboflavin-Overproducing Limosilactobacillus reuteri for Biofortification of Fermented Foods

“…Galleria mellonella larvae were purchased from Anaconda reptiles (Kontich, Belgium), the larvae were then stored at 4°C and were used within 7 days. Safety testing was performed as described in De Boeck et al ( 35 ), with 15 larvae used per treatment group. The safety of bacteria was tested by injecting 10 μl of a 10 3 CFU/ml bacterial solution in the last prolegs of the larvae and monitoring larvae survival for 144 h. PBS was used as a negative control.…”

“…Testing was performed cfr. ( 35 ). Briefly, pathogen cultures of Listeria monocytogenes LMG 23194, Shigella sonnei LMG10473, and Salmonella enterica subsp.…”