Most of the antibiotics that we use derive from substances excreted by the bacteria species Streptomyces. They produce antimicrobial agents, including antibiotics. The bacteria themselves use their antimicrobial agents to fight off hostile micro-organisms, including other bacteria or fungi.
From the soil to the air
While Streptomyces occur primarily in the soil, they can also be found on insects. New research conducted by scientists at the University of Wisconsin-Madison shows that the species in the soil and those on insects differ enough from one another to produce different antimicrobial agents as well. In fact, the various Streptomyces species on insects have specifically adapted to live on certain bugs such as grasshoppers, beetles, ants, butterflies, bees and many others, meaning that a huge range of antimicrobial products exist.
Further research on mice revealed that the Streptomyces found on insects were better at combating the bacterial pathogens E. coli, P. aeruginosa and the fungal pathogen C. albicans than the species which live in the soil and on plants. Most of the antimicrobial products were also found to have no side effects. These products will now be modified so they can ultimately be tested on humans. It will take some time, however, before that stage has arrived. Still, this study shows that new antibiotics can emerge from the most unexpected nooks and crannies – with a little luck.