Comparative transcriptomics analysis of multidrug-resistant Acinetobacter baumannii in response to treatment with the terpenic compounds thymol and carvacrol.

Acinetobacter baumannii is a gram-negative opportunistic bacterium that has become a major public health concern and a substantial medical challenge due to its ability to acquire multidrug resistance (MDR), extended-drug resistance, or pan-drug resistance. In this study, we evaluated the antibacterial activity of thymol and carvacrol alone or in combination against clinical isolates of MDR A. baumannii. Additionally, we used RNA-sequency to perform a comparative transcriptomic analysis of the effects of carvacrol and thymol on the Acb35 strain under different treatment conditions. Our results demonstrated that thymol and carvacrol alone, effectively inhibited the bacterial growth of MDR A. baumannii isolates, with a minimum inhibitory concentration (MIC) lower than 500 µg/mL. Furthermore, the combination of thymol and carvacrol exhibited either synergistic (FICI ≤ 0.5) or additive effects (0.5 < FICI ≤ 4), enhancing their antibacterial activity. Importantly, these compounds were found to be non-cytotoxic to Vero cells and did not cause hemolysis in erythrocytes at concentrations that effectively inhibited bacterial growth. Transcriptomic analysis revealed the down-regulation of mRNA associated with ribosomal subunit assemblies under all experimental conditions tested. However, the up-regulation of specific genes encoding stress response proteins and transcriptional regulators varied depending on the experimental condition, particularly in response to the treatment with carvacrol and thymol in combination. Based on our findings, thymol and carvacrol demonstrate promising potential as chemotherapeutic agents for controlling MDR A. baumannii infections. These compounds exhibit strong antibacterial activity, particularly in combination and lower cytotoxicity towards mammalian cells. The observed effects on gene expression provide insights into the underlying mechanisms of action, highlighting the regulation of stress response pathways.

Plant protection from virus: a review of different approaches.

This review analyzes methods for controlling plant viral infection. The high harmfulness of viral diseases and the peculiarities of viral pathogenesis impose special requirements regarding developing methods to prevent phytoviruses. The control of viral infection is complicated by the rapid evolution, variability of viruses, and the peculiarities of their pathogenesis. Viral infection in plants is a complex interdependent process. The creation of transgenic varieties has caused much hope in the fight against viral pathogens. The disadvantages of genetically engineered approaches include the fact that the resistance gained is often highly specific and short-lived, and there are bans in many countries on the use of transgenic varieties. Modern prevention methods, diagnosis, and recovery of planting material are at the forefront of the fight against viral infection. The main techniques used for the healing of virus-infected plants include the apical meristem method, which is combined with thermotherapy and chemotherapy. These methods represent a single biotechnological complex method of plant recovery from viruses in vitro culture. It widely uses this method for obtaining non-virus planting material for various crops. The disadvantages of the tissue culture-based method of health improvement include the possibility of self-clonal variations resulting from the long-term cultivation of plants under in vitro conditions. The possibilities of increasing plant resistance by stimulating their immune system have expanded, which results from the in-depth study of the molecular and genetic bases of plant resistance toward viruses and the investigation of the mechanisms of induction of protective reactions in the plant organism. The existing methods of phytovirus control are ambiguous and require additional research. Further study of the genetic, biochemical, and physiological features of viral pathogenesis and the development of a strategy to increase plant resistance to viruses will allow a new level of phytovirus infection control to be reached.