Increases in the numbers of immunocompromised patients and the emergence of drug-resistance fungal pathogens have led to the need for new, safe, efficacious antifungal agents. In this study, we designed a histidine-lysine-lysine (HKK) motif and synthesized six HKK peptides with repetitions of the motif. These peptides showed length-dependent antifungal activity against drug-susceptible and drug-resistant fungal pathogens via membranolytic or non-membranolytic action. None of the peptides were cytotoxic to rat erythrocytes or NIH3T3 mouse embryonic fibroblasts. Short-length peptides were directly translocated in fungal cytosol and reacted with mitochondria, resulting in apoptosis. Membrane-permeabilizing activity occurred in the presence of long peptides, and peptides were able to transfer to the cytosol and induce reactive oxygen species. Our results suggest that peptides composed only of cationic amino acids may be good candidates as antifungal agents.
In South Korea, LM crops are not allowed to grow locally, but have been allowed to be imported as food and feed purposes. Currently, the typical LMO imports are continuously increasing in the region of South Korea. In 2014, we carried out a review of the environmental release monitoring of LM maize (Zea mays L.) in Gyeonggi-do of South Korea, and analyzed volunteer samples using strip test kits and polymerase chain reaction (PCR) methods. We thereby collected 44 volunteers of released LM maize in 169 locations around ports, from roadsides, feed factories and stockbreeding farmhouses. We found 4 positive samples at 3 sites using strip test kits. Based on the PCR analysis, the LM maize plants were found using event-specific primers. These results suggested that our monitoring is necessary to detect the presence of released LM maize in the natural environment of South Korea.
The effect of amplifying growth-related receptor signaling, through overexpression of receptors, on growth regulation in animals was examined. Transgenic mice lines were produced by DNA microinjection using the metallothionein promoter ligated to either the growth hormone receptor (GHR) or IGF-1 receptor (IGF-1R) genes (3 GHR founders and 3 IGF-1R founders). Transgenic mouse lines were estimated to contain approximately 4 to 20 copies of transgenes per cell by Southern blot analysis. Founder mice of each transgenic line transmitted transgenes into F1 and F2 pups with Mendelian ratio. Double transgenic (IGF-1R/GHR) mice were produced by the mating between nine pairs of IGF-1R and GHR hemizygous transgenic F1 mice. The transmission patterns in the 78 F2 pups produced from these matings were 20 with no transgene (25.6%), 17 with the IGF-1R gene (21.8%), 25 with the GHR gene (32.1%), and 16 with both GHR and IGF-1R genes (20.5%). The mRNA expression of transgenes using RT-PCR with the specific primers for IGF-IR and GHR genes was checked in tissues of transgenic mice. Double transgenic mice with IGF-IR and GHR genes expressed more mRNAs of transgenes than non-transgenic or single transgenic mice. Growth of double transgenic mice was fastest compared with single transgenic mice containing IGF-1R or GHR genes. And GHR transgenic mice grew faster than IGF-1R transgenic mice. When body weights of 15 transgenic mice for each transgenic line were measured at 4, 10, and 14 weeks after birth, double transgenic mice were significantly heavier compared with non-transgenic control mice at each stage (24 to 30% heavier in double transgenic mice; 15 to 20% heavier in single transgenic mice, P < 0.05). These results suggest that overexpression of growth-related receptor genes could promote the growth of transgenic animals with an additive effect.
Abstract The insecticidal toxin gene of Bacillus thuringiensis ( Bt ) is the most commonly used to develop insect‐resistant living modified organisms (LMOs). Insecticidal proteins produced in transgenic plants are released into the soil from the roots. In this study, possible effects of crystal 1Ac (Cry1Ac) protein on the soil microbial community in Korea were studied. To purify the insoluble Cry1Ac protein expressing Escherichia coli cells, we performed repeated sonication and PBS washing of the insoluble part and Cry1Ac protein was isolated in soluble form from the insoluble form using 100 mM Na 2 CO 3 buffer (pH 9.6) without affinity bead. Also, size‐exclusion chromatography (SEC) was performed to increase the purity of the isolated Cry1Ac protein. The final protein product was identified as Cry1Ac protein through MALDI‐TOF. Insecticidal activity of Cry1Ac protein was demonstrated through the death of Plutella xylostella treated with Cry1Ac protein. Purely isolated Cry1Ac protein showed the same insecticidal activity as Cry1Ac expressed in LM crops. To investigate the change of soil microbial distribution using maize field soils treated with Cry1Ac protein, we isolated high quality metagenomic DNAs from buffer‐ and Cry1Ac protein‐treated soil groups, and analyzed the distribution of soil microorganisms through next‐generation sequencing (NGS) analysis. NGS results showed a similar microbial distribution in both buffer‐ and Cry1Ac protein‐treated samples. These results suggest a useful risk assessment method for domestic targeted insect and soil microorganisms using the Cry1Ac protein.
Objective HPV Test [Invader Technology/Real-Time PCR] is a molecular genetic test performed for confirming the presence of infection by detecting 14 types of HPV and additionally, for classifying types 16 and 18 genotypes. Methods It was assessed using 8 domestic databases including Korea Med and Ovid-MEDLINE, Ovid-EMBASE. 1,214 works were identified. Of them, animal experimental or studies not published in Korean or English were excluded. Total of 23 literatures composed of 8 literatures for Invader Technology and 15 literatures on Real-Time PCR were included in the final assessment. Two reviewers screened all references independently, for assessing included articles quality and extracted data. Results Index tests were assessed to be a safe test, since it does not impart direct harm to the patients as it is conducted outside the patients body by collecting uterus cervical cells. Effectiveness was assessed by diagnostic accuracy, concordance rate, detection rate. Diagnostic accuracy of Invader Technology with sequencing was high (sensitivity=0.89, specificity=0.92). As the result of comparison between Invader Technology and Hybrid Capture 2(HC2), the false positive rate of index test (5.8%) was lower than HC2 (5.5–21.9%). The concordance rate was 83.1%-94.0%. Diagnostic accuracy of Real-Time PCR with DNA chip was high level (sensitivity=0.96, specificity=1.00). Rate of concordance between Real-Time PCR and HC2 was in the range of 82.6–98.3%, with DNA chip was in the range of 66.7–98.3%. Conclusion These tests are safety. Also, there are the effectiveness of additional diagnosis for genotypes 16 and 18, high level of concordance with the existing tests and high level of detection of HPV genotypes 16 and 18 in high risk group.