Exploiting oxalotrophic bacteria to control Aspergillus niger lung infections

Fungal diseases are currently affecting a record number of people around the globe, with the genus representing one of the most prevalent groups of opportunistic fungal pathogens. Many aspects of the ecology of spp. are linked to pathogenicity, but so far, the ability to enhance their infectious potential by manipulating the environmental pH has not been considered. In this study we tested the hypothesis that by producing oxalic acid, can manipulate pH during lung infection and thus interfering with this process limits pathogenicity. To test this hypothesis, we co-cultured with bacteria that degrade oxalic acid (oxalotrophic bacteria) , as well as using undifferentiated and differentiated lung cells in Transwells inserts or bronchioles-on-a-chip systems. In the tests oxalotrophic bacteria suppressed the pH shift induced by , thereby effectively stopping growth. In systems, also modified pH, Ca and oxalic acid concentrations. Co-inoculation with as little as 10 cells of the oxalatrophic bacterium strongly inhibited the germination and development of and returned each of the three parameters to the baseline physiological values of uninfected cells. This offers the first demonstration of the use of oxalotrophic bacteria to control the growth of and represents a novel treatment paradigm that focuses on the manipulation of the environment as part of medical interventions to fight opportunistic fungal pathogens.