Antisense RNA, the modified CRISPR-Cas9, and metal/metal oxide nanoparticles to inactivate pathogenic bacteria

Abstract

Finding efficient therapeutic strategies to fight antibiotic-resistant bacteria is a complicated affair specifically in the therapy of chronic bacterial infections related to hospital-acquired infections. Recently, three major antibacterial systems based on antisense RNA, CRISPR-Cas9, and metal/metal oxide nanoparticles particularly silver (Ag) nanoparticles have shown more effective antibacterial activity compared to conventional antibiotics. ROS generation, attachment to the cell membrane, disruption of bacterial envelop, inactivation of electron transport chain, decreasing the local pH, modulation of cell signaling, and denaturation of biological macromolecules such as proteins and nucleic acids have been found as the main antibacterial functions of Ag nanoparticles. Antisense RNA, a single-stranded RNA, can hybridize with complementary genes in messenger RNA (mRNA) followed by blockage translation of these genes into proteins. Moreover, CRISPR (clustered regularly interspaced short palindromic repeats) is a family of viral DNA sequences derived from bacteriophages, which can target and destroy foreign DNA by nuclease activity. There are 2 classes and 6 subtypes (I-VI) of CRISPR-Cas systems, which may be engineered as potential antibacterial agents to target specific sequences. Therefore, here, recent advances and challenges for the antibacterial application of these three therapeutic agents are presented.

Evaluation of Active Pulmonary Tuberculosis Among Women With Diabetes

“…Three persons (4.92%) of the diabetic-TB patients and 1 person (1.59%) of nondiabetic-TB patients had upper lower left part reticulonodular infiltration in their chest graph (p=0.4). One person (1.64%) of the diabetic-TB patients had left upper and lower zone fibrosis in their chest radiography and none of the non-diabetic-TB patients had left upper& lower zone fibrosis (p=0.5) (Table 1- 5).…”

“…Recently, finding an effective therapy for hindering bacterial, fungal, and viral infections have obtained high attention [1][2][3][4][5]. Tuberculosis is a kind of bacterial infection that is caused by Mycrobacterium tuberculosis [6].…”

Surface modification of SiO2 nanoparticles for bacterial decontaminations of blood products

“…As shown in Figure 2, other components of the bacterial envelope, including capsule, fimbriae, pilus, flagellum, teichoic acid and lipoteichoic acid of Grampositive bacteria, and lipopolysaccharide of Gram-negative bacteria could be targeted by functionalized SiO2NPs [68]. In order to achieve synergistic antimicrobial activity against bacteria or viruses, antibacterial or antiviral agents such as metals, metal oxide NPs or antibiotics can be employed to functionalize SiO2NPs to produce reactive oxygen species (ROS) that can then damage biological macromolecules (Figure 3e) [70][71][72]. The use of organosilane-based coupling agents is the main way to prepare different derivatives of SiO2NPs (Figure 3a-3d) [58,73].…”

Determination of efflux activity in Enterococci by Hoechst accumulation assay and the role of zinc oxide nanoparticles in inhibition of this activity

“…However, the exact mechanism has not been completely defined. In review studies by Alavi et al [ 15 , 16 ] on antibacterial properties of NPs, various mechanisms were pointed out, including increase in the permeability of antibiotics into the cells, pore creation and membrane destruction, prevention of biofilm formation, inactivation of electron transfer chain, production of reactive oxygen species (ROS), denaturation of macromolecules, and effect on cellular signals. Taken together, more potential of ZnONPs than CCCP in dye accumulation, suggests that it can be a suitable candidate for anti-efflux studies in future.…”