Optimization of abiotic factors for improved growth and extracellular production of recombinant fungal phytase in sesame hairy root cultures

CRISPR/Cas9-Mediated Efficient Targeted Mutagenesis in Sesame (Sesamum indicum L.)

The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) system has been widely utilized for targeted genome modification in a wide range of species. It is a powerful genome editing technology, providing significant benefits for gene functional research and molecular breeding. However, to date, no study has applied this genome editing tool to sesame (Sesamum indicum L.), one of the most ancient and important oil crops used widely in diverse industries such as food and medicine. Herein, the CRISPR/Cas9 system along with hairy root transformation was used to induce targeted mutagenesis in sesame. Two single guide RNAs (sgRNAs) were designed to target two sesame cytochrome P450 genes (CYP81Q1 and CYP92B14), which are the key biosynthetic gene of sesamin and sesamolin, respectively. Sequencing data illustrated the expected InDel mutations at the target sites, with 90.63 and 93.33% mutation frequency in CYP81Q1 and CYP92B14, respectively. The most common editing event was single nucleotide deletion and insertion. Sequencing of potential off-target sites of CYP92B14-sgRNA showed no off-target events in cases of three mismatches. High-performance liquid chromatography analysis showed that sesamin and sesamolin biosynthesis was effectively disrupted in the mutated hairy roots, confirming the crucial role of CYP81Q1 and CYP92B14 in sesame lignan biosynthesis. These results demonstrated that targeted mutagenesis was efficiently created by the CRISPR/Cas9 system, and CRISPR/Cas9 coupled with hairy root transformation is an effective tool for assessing gene functions in sesame.

Establishment and elicitation of transgenic root culture of Plantago lanceolata and evaluation of its anti-bacterial and cytotoxicity activity

Hairy root induction in Plantago lanceolata was optimized to take advantage of transformed root cultures. The highest frequency of transformation was achieved using leaf explant, A4 strain, pre-cultivation of explant, 150 µM Acetosyringone, 5 min inoculation, half-strength Murashige and Skoog basal medium as co-cultivation, and half-strength Gamborg's basal medium as a selective medium with 3% sucrose. Among the studied compound encompassing gallic acid, catalpol and apigenin, only the production of gallic acid in hairy roots was affected by 20 mg L^-1 AgNO₃ and 100 mg L^-1 chitosan at 24 hr which yielded 7.63, 4.76-fold increase in its content, respectively. The methanolic extracts of hairy roots elicited by 20 mg L^-1 AgNO₃ exhibited anti-bacterial activity (MIC and MBC = 25 mg mL^-1) against Klebsiella pneumoniae, Proteus vulgaris and Salmonella typhi and anti-bacterial potential of non-elicited hairy roots of P. lanceolata (MIC = 25 mg mL^-1 and MBC = 35 mg mL^-1) were more active against Klebsiella pneumoniae and P. vulgaris than other bacteria. The methanolic extracts of the P. lanceolata hairy roots demonstrated significant cytotoxic activity on colorectal carcinoma cell line (SW-480) with IC₅₀ = 250.65 ± 6.8 µg mL^-1 in comparison to human embryonic kidney (HEK-293) with IC₅₀ = 5263.65 ± 4.6 µg mL^-1. Plantago lanceolata hairy roots showed important biological activity explaining its role in traditional medicine.

Simultaneous quantitative detection of 12 pathogens using high-resolution CE-SSCP

Several methods based on screening for a 16S ribosomal RNA gene marker have been developed for rapid and sensitive detection of pathogenic microorganisms. One such method, CE-based SSCP (CE-SSCP), has enormous potential because the technique can separate sequence variants using a simple procedure. However, conventional CE-SSCP systems have limited resolution and cannot separate most 16S ribosomal RNA gene-specific markers unless combined with additional modification steps. A high-resolution CE-SSCP system that uses a poly(ethyleneoxide)-poly(propyleneoxide)-poly(ethyleneoxide) triblock copolymer matrix was recently developed and shown to effectively separate highly similar PCR products. In this study, we developed a method based on a high-resolution CE-SSCP system using a poly(ethyleneoxide)-poly(propyleneoxide)-poly(ethyleneoxide) triblock copolymer that is capable of simultaneous and quantitative detection of 12 clinically important pathogens. Pathogen markers were amplified by PCR using universal primers and separated by CE-SSCP; each marker peak was well separated at baseline and showed a characteristic mobility, allowing easy identification of pathogens. A series of experiments using different amounts of genomic pathogen DNA showed that the method had a limit of detection of 0.31-1.56 pg and a dynamic range of approximately 10(2). These results indicate that high-resolution CE-SSCP systems have considerable potential in the clinical diagnosis of bacteria-induced diseases.