Antibiotics have entered human life over half a century ago. They were the reason pneumonia, tuberculosis, gangrene and other infections lost their lethality for human beings. But even most powerful antibiotics cannot kill all pathogenic bacteria in the world.
Nature hates emptiness. For fighting pharmaceuticals bacteria “launched” natural genetic mechanisms in order to form resistance. These mechanisms resulted in new generations of microbes, which are resistant to even most powerful treating agents. Every year there appear more and more “resistant” infections – that is why medics all around the world do their best to find new methods of fighting dangerous invincible bacteria. Scientists from Moscow science and research centre for new antibiotics’ search have made a significant progress in this hard task.
For a long time soil bacteria – actinomycetes – were main object for searching new antibacterial agents, and recently higher fungi joined the institute’s search. Microbiologists have developed techniques for selective isolation of actinomycetes from soil samples, allowing detecting species of bacteria, which have never grown in laboratory conditions before. For example, soil exposure to ultraviolet radiation, super-high-frequency (SHF) and extremely high frequency (EHF) electromagnetic waves gives very high probability of isolating rare species of actinomycetes. This fat is very important, because an organism, producing new antibiotic daptomycin, can be met only once among 10 million of other cells.
New methods allowed institute fellows to study 9280 organisms, isolated from natural substrates, for the period of recent four years. 1169 organisms contained antibiotics, which were effective against a resistant strain MRSA of Staphylococcus aureus. 265 agents were considered to be most promising pharmaceuticals, and their chemical composition was analyzed. 28 substances appeared to be already known antibiotics, and 36 – to be totally new ones. But only seven out of all agents showed high therapeutic effect and low toxicity, when tested on animals.
Thanks to the institute fellows’ studies Russia finally, after 20-year break, starts commercial production of a new glycopeptide antibiotic eremomycin. This development is 17th for the whole period of the institute’s existence. The antibiotic has come a long way before the production started: first an actinomycete strain was isolated from soil, and its taxonomic status was identified (Amycolatopsis orientalis subsp. eremomycini); then the spectrum of sensitive microorganisms was specified; the technique of strain isolation was practiced; antibiotic’s chemical composition was specified; strain’s productivity was increased by selection techniques, and commercial producer-strain was developed. Also biologists have developed the technique for new agent’s biosynthesis and tested in on animals, not to forget clinical trials performed. New Russian antibiotic eremomycin effectively acts on many resistant strains of pathogenic bacteria, including Staphylococcus aureus MRSA strain.
Phenomenon of bacterial resistance keeps scientists and producers from “retiring on their laurels”, because it requires development and introduction of more and more new effective treating agents. Unfortunately, last 20 years in Russia didn’t bring much innovation in biotechnology and related field of producing pharmaceuticals. At the best case native producers have released so-called generics – analogues of foreign treating agents, which license has expired. Thus, development and introduction of new antibiotics should become the priority of Russian science and technology for the nearest future.
Sources:
www.cbio.ru
www.nkj.ru
Anna Kizilova