Gellan gum-based media recover more diverse microbial communities from soil material

Soil microbial communities contain a huge proportion of microorganisms that cannot be cultured using standard microbiological media and are accessible only through molecular methods. These uncultivable microbes may include producers of biologically active compounds valuable for medicine, biotechnology, and agriculture. Development of approaches for cultivation of such groups is of paramount importance. Here we successfully replicate and confirm the accumulated observations on the fact that replacing agar with gellan gum as gelling agent and using nutrient-poor media leads to the more frequent recovery and enrichment of rare and hard-to-culture microbial phyla representatives. We also show that altering the gas mixture in the incubation chamber may promotes the isolation of specific microbial groups. Replacing agar with gellan gum is suggested as a strategy to recover new microbial species.