Development of a transcription factor decoy-nanocarrier system as a successful inhibitor of Enterococcus faecalis virulence in vitro and in vivo.

Enterococcus faecalis is a troublesome nosocomial pathogen that acquired resistance to most available antimicrobial agents. Antivirulence agents represent an unconventional treatment approach. Here, transcription factor decoy (TFD)-loaded cationic liposomes (TLL) were developed as an inhibitor of the Fsr quorum-sensing system and its associated virulence traits, in E. faecalis. The consensus sequence of the FsrA binding site was found conserved among 651 E. faecalis annotated genomes. The TFD was synthesized as an 82 bp DNA duplex, containing the conserved binding sequence, and loaded onto cationic liposomes. The optimum loading capacity, mean particle size, and zeta potential of the TLL were characterized. The developed TLL lacked any effect on E. faecalis growth and significantly inhibited the in vitro production of the proteolytic enzymes controlled by the Fsr system; gelatinase and serine protease, in a concentration-dependent manner. This inhibition was accompanied by a significant reduction in the transcription levels of FsrA-regulated genes (fsrB, gelE, and sprE). The developed TLL were safe as evidenced by the nonhemolytic effect on human RBCs and the negligible cytotoxicity on human skin fibroblast cells. Moreover, in the larvae infection model, TLL displayed a significant abolish in the mortality rates of Galleria mellonella larvae infected with E. faecalis. In conclusion, the developed TLL offer a new safe strategy for combating E. faecalis infection through the inhibition of quorum-sensing-mediated virulence; providing a platform for the development of similar agents to combat many other pathogens.

Alterations in Biomarkers Associated with Sterility in Pectinophora gossypiella (Saunders) Induced by Gamma Irradiation

ABSTRACT Nowadays, radiation technology is widely used to produce changes in Biosystems. The goal of this work is to determine the variation induced male Pectinophora gossypiella in gamma-irradiated as pupae using 50Gy and 150Gy. Comparing elements composition and DNA (using RAPD-PCR) between substerile 50Gy and the sterile dose 150Gy in P. gossypiella showed variation between them. Potassium (K) was the most abundant elements in unirradiated and irradiated males followed by magnesium (Mg). The percentage of heavy metals as copper, zinc, and cadmium concurrent with K was directly proportional to the radiation dose. While the percentage of Mg, Phosphorous and calcium decreased as the radiation dose increased. The results also revealed that some extra bands appeared and others disappeared, as a result of irradiation. The appearance of extra bands may be due to the repair mechanism of the irradiation damaged DNA. The banding patterns obtained and the dendrograms drawn on the basis of presence and absence of bands revealed that 150Gy irradiated pupae are more different from the unirradiated pupae than the 50Gy irradiated pupae. It was concluded that the sterile male technique could be used as a benefit tool in controlling P. gossypiella.

Changes occurred in the testes and DNA pattern of males wax moth (Galleria mellonella) first generation as a result of irradiation of their parents.

Nowadays, the sterile insect technique is broadly used as a pest control measure. Therefore, the present study was conducted to investigate the alteration occurred in testes and DNA pattern as an effect of inherited sterility. Full grown pupae of the wax moth, Galleria mellonella were irradiated with 80 and 160 Gy of γ irradiation. The size of the testes was decreased by increasing of γ irradiation dose. Also, the size of the testes was decreased in F 1 males comparing with the size of the testes of both the parents and the untreated control. The effects of γ rays on the DNA patterns of adult male parents and F 1 males showed alterations among the controls, the treated parents and F 1 individuals. Exposure to radiation caused very frequently the appearance of some extra bands and the deficiency of others in the arbitrary random amplified polymorphic DNA-polymerase chain reaction amplification patterns of the irradiated insects.

Alterations in Biomarkers Associated with Sterility in Pectinophora gossypiella (Saunders) Induced by Gamma Irradiation

ABSTRACT Nowadays, radiation technology is widely used to produce changes in Biosystems. The goal of this work is to determine the variation induced male Pectinophora gossypiella in gamma-irradiated as pupae using 50Gy and 150Gy. Comparing elements composition and DNA (using RAPD-PCR) between substerile 50Gy and the sterile dose 150Gy in P. gossypiella showed variation between them. Potassium (K) was the most abundant elements in unirradiated and irradiated males followed by magnesium (Mg). The percentage of heavy metals as copper, zinc, and cadmium concurrent with K was directly proportional to the radiation dose. While the percentage of Mg, Phosphorous and calcium decreased as the radiation dose increased. The results also revealed that some extra bands appeared and others disappeared, as a result of irradiation. The appearance of extra bands may be due to the repair mechanism of the irradiation damaged DNA. The banding patterns obtained and the dendrograms drawn on the basis of presence and absence of bands revealed that 150Gy irradiated pupae are more different from the unirradiated pupae than the 50Gy irradiated pupae. It was concluded that the sterile male technique could be used as a benefit tool in controlling P. gossypiella.