Broad-spectrum antibiotic estimated 10-100 trillion multiple organisms that colonize the human body. As a side-effect of therapy, antibiotics can change the body's normal microbial content by attacking indiscriminately both the pathological and naturally occurring, beneficial or harmless bacteria found in the intestines, lungs and bladder. The destruction of the body's normal bacterial flora is thought to disrupt immunity, nutrition, and lead to a relative overgrowth in some bacteria or fungi. An overgrowth of drug-resistant microorganisms can lead to a secondary infection such as "Clostridium difficile" ("C. diff") or candidiasis ("thrush"). This side-effect is more likely with the use of broad-spectrum antibiotics, given
Fungal-bacterial endosymbiosis associations. What is known on these associations impacts our understanding of the ecological interactions of plants, fungi and bacteria. The classification of bacterial endosymbionts and their fungal partners occur across a diverse set of phyla. Ca. G. sporarum and Burkholderia sp. have been identified to be β-proteobacteria, a gram-negative class of bacteria, and N. punctiforme is a cyanobacteria . These phyla are not closely related showing that the capability of endosymbiosis with fungi is widely spread. A similar pattern is seen with the fungal partners with examples occurring across broad phyla/divisions such as Glomeromycota, Zygomycota, Ascomycota and Basidiomycota. The common