Deciphering the role of Burkholderia cenocepacia membrane proteins in antimicrobial properties of chitosan

Abstract

Chitosan, a versatile derivative of chitin, is widely used as an antimicrobial agent either alone or mixed with other natural polymers. Burkholderia cenocepacia is a multidrug-resistant bacteria and difficult to eradicate. Our previous studies shown that chitosan had strong antibacterial activity against B. cenocepacia. In the current study, we have investigated the molecular aspects for the susceptibility of B. cenocepacia in response to chitosan antibacterial activity. We have conducted RNA expression analysis of drug efflux system by RT-PCR, membrane protein profiling by SDS-PAGE, and by LC-MS/MS analysis following the validation of selected membrane proteins by real-time PCR analysis. By RT-PCR analysis, it was found that orf3, orf9, and orf13 were expressed at detectable levels, which were similar to control, while rest of the orf did not express. Moreover, shotgun proteomics analysis revealed 21 proteins in chitosan-treated cells and 16 proteins in control. Among them 4 proteins were detected as shared proteins under control and chitosan-treated cells and 17 proteins as uniquely identified proteins under chitosan-treated cells. Among the catalog of uniquely identified proteins, there were proteins involved in electron transport chain and ATP synthase, metabolism of carbohydrates and adaptation to atypical conditions proteins which indicate that utilization and pattern of chitosan is diverse which might be responsible for its antibacterial effects on bacteria. Moreover, our results showed that RND drug efflux system, which display the ability to transport a variety of structurally unrelated drugs from a cell and consequently are capable of conferring resistance to a diverse range of chemotherapeutic agents, was not determined to play its role in response to chitosan. It might be lipopolysaccharides interaction with chitosan resulted in the destabilization of membrane protein to membrane lyses to cell death. Membrane proteome analysis were also validated by RT-qPCR analysis, which corroborated our results that of membrane proteins.

Antibacterial activity of chitosan against Burkholderia pseudomallei

“…Chitosan at a concentration of In those cases, effective concentrations of chitosan were 10-100 μg ml −1 (Fang et al, 2010). Activity of chitosan against B. cenocepacia, a multidrug-resistant pathogen that is difficult to eradicate, has also been demonstrated (Ibrahim et al, 2014). Leaving aside human pathogens, the apricot fruit-rot pathogen, B. seminalis, could be eradicated by treatment with chitosan at 2 mg ml −1 (Lou et al, 2011).…”

“…Another study on members of the same complex was conducted in sputum from cystic fibrosis (CF) patients in China (Fang et al., ). The third report focused on the multidrug‐resistant B. cenocepacia (Ibrahim et al., ). Chitosan can lethally damage bacterial cell membranes leading to the leakage of proteins, nucleic acids and other intracellular components.…”

“…The third report focused on the multidrug-resistant B. cenocepacia (Ibrahim et al, 2014). Chitosan can lethally damage bacterial cell membranes leading to the leakage of proteins, nucleic acids and other intracellular components.…”

Nanotechnological approaches for the development of novel antimicrobial strategies

“…On the other side, Ch has been demonstrated to inhibit the antimicrobial effect of a metallic nanomaterials, such as ZnNPs (Huh and Kwon 2011). The antimicrobial mode of action Ch NPs is not entirely understood (Ibrahim et al, 2014). Previous studies have indicated disruption of cell membrane functions (proteins inactivation, interfering with respiratory chain, drug efflux system and transport), resulting in membrane lysis and cell death (Bratlie et al, 2012).…”

Algal Nanoparticles: Synthesis and Biotechnological Potentials

“…The use of chitosan along with metal nanoparticles is not feasible since chitosan reduced the activity of metal nanoparticles such as Zn. It can be used in combination with antibiotics [76,78]. Even though some studies state that the interaction of cells with chitosan lead to membrane destabilization, followed by lysis and cell death, the detailed mode of action is unclear [79].…”