Black Sea bacteria - new drugs source
Nowadays, there is an urgent need for new drugs to fight infectious diseases as antibiotic resistance has become one of the main threats to global health.
The marine environment has been described as a source of bioactive metabolites with potential medical utilities. Marine bacteria can produce several types of secondary metabolites, namely macrolides, cyclic peptides, polyketides, terpenes, alkaloids and steroid alkaloids.
Marine Actinobacteria and bacteria genus Pseudomonas are among the most widespread microorganisms in the ocean.
More than 5,000 secondary metabolites with antibiotic activity were identified in Actinobacteria, which are the most important source of biologically active natural products for clinical or pharmaceutical applications. According to the literature, actinobacteria exhibiting high antagonistic activity encode at least one type of polyketide synthase biosynthesis gene (PKS-I, PKS-II), which are responsible for the synthesis of new secondary metabolites and have the potential for the discovery of new drugs.
Bacteria from the genus Pseudomonas are capable of forming complex communities called biofilms. Biofilms consist of dense populations of bacteria embedded in a biological matrix that binds the bacteria to each other and to the surface. In marine biofilms, bacteria were packed together at a density three orders of magnitude greater than that of their planktonic counterparts. At such a density, intercellular interactions were enhanced, and these interactions affected the expression of their genes and the production of secondary metabolites.
Active work is currently underway to isolate new strains of marine Actinobacteria from the Black Sea, identify them, and study their main biological properties such as antagonistic activity against strains of opportunistic bacteria. In addition, the effects of extracts isolated from marine Pseudomonas strains after mono- and co-cultivation on Micrococcus bacteria are being investigated to determine their antimicrobial activity. In general, studying the antagonistic activity of marine strains and determining the profiles of their metabolites is promising for the further search for new antimicrobial compounds, including against mycobacteria.