Bacteria are incredibly diverse and live in most habitats on the planet, from intense cold to extreme heat, and even in radioactive waste – in fact, the biomass of bacteria exceeds that of all the animals and plants on the earth. Over the last decade or so, the number of bacterial species that scientists believe to exist on Earth has increased enormously, as knowledge grows and technologies improve. Researchers from the US have continued this exploration by using the polymerase chain reaction (PCR) to analyse bacteria in desert soils, and have found that different samples including vastly different collections of biosynthetic genes that could have use in developing new naturally-derived products.
The team of scientists isolated bacteria from three different samples of arid soils in desert areas of the American Southwest – the Sonoran Desert of Arizona, the Anza Borrego section of the Sonoran Desert of California, and the Great Basin Desert of Utah. Many of these bacteria cannot be cultured, and so the researchers created large metagenomic libraries (libraries of all the genes of all the bacteria in a sample) using PCR and screened these libraries for genes linked with biosynthesis, looking for similarities and differences. Even though the ecology of each region was similar, the collections of biosynthetic genes were very different, and the results were published in Applied and Environmental Microbiology.
The majority of new drugs approved by the US Food and Drug Administration are natural products, and most of these come from bacteria, including antibiotics and anticancer agents. This study suggests that there are biosynthetic bacteria out there that have been missed in the past, and that could be used to produce useful products such as drugs, biofuels, enzymes, plastics and other polymers.
“Our work suggests that the genomes of environmental bacteria could encode many additional drug-like molecules, including compounds that might serve, among other things, as new antibiotics and anticancer agents,” says Sean Brady of the Howard Hughes Medical Institute, Rockefeller University, New York. “This is a small preliminary study that warrants additional investigations of more environments and more extensive sequence analysis, but it suggests that environmental bacteria have the potential to encode a large additional treasure trove of new medicines.”
Suzanne Elvidge is a freelance science, biopharma, business and health writer with more than 20 years of experience. She is editor of Genome Engineering, a blog that monitors the latest developments in genome engineering and that aims to educate (and sometimes to entertain!) and has written for a range of online and print publications including FierceBiomarkers, FierceDrugDelivery, European Life Science, the Journal of Life Sciences (now the Burrill Report), In Vivo, Life Science Leader, Nature Biotechnology, PR Week and Start-Up. She specialises in writing on pharmaceuticals, biotechnology, healthcare, science, lifestyle and green living, but can write on any topic given enough tea and chocolate biscuits. She lives just beyond the neck end of nowhere in the Peak District with her second-hand bookseller husband and two second-hand cats.