• ALGAE
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• v.35 no.2
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• pp.177-187
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• 2020

Cyanobacteria have been widely reported to produce a variety of UV-absorbing mycosporine-like amino acids (MAAs). Herein, we reported production of the unusual MAA, mycosporine-glycine-alanine (MGA) in the cyanobacterium Sphaerospermopsis torques-reginae ITEP-024 using a newly developed UHPLC-DAD-MS/HRMS (ultra-high performance liquid chromatography-diode array detection-high resolution tandem mass spectrometry) method. MGA had previously been first identified in a red-algae, but S. torques-reginae strain ITEP-024 is the first cyanobacteria to be reported as an MGA producer. Herein, the chemical structure of MGA is fully elucidated from one-dimensional / two-dimensional nuclear magnetic resonance and HRMS data analyses. MAAs are unusually produced constitutively in S. torques-reginae ITEP-024, and this production was further enhanced following UV-irradiance. It has been proposed that MAA biosynthesis proceeds in cyanobacteria from the pentose phosphate pathway intermediate sedoheptulose 7-phosphate. Annotation of a gene cluster encoded in the genome sequence of S. torques-reginae ITEP-024 supports these gene products could catalyse the biosynthesis of MAAs. However, addition of glyphosate to cultures of S. torques-reginae ITEP-024 abolished constitutive and ultra-violet radiation induced production of MGA, shinorine and porphyra-334. This finding supports involvement of the shikimic acid pathway in the biosynthesis of MAAs by this species.

• Journal of Microbiology and Biotechnology
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• v.31 no.1
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• pp.144-153
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• 2021

Organophosphorus nerve agents (OPNAs), including both G- and V-type nerve agents such as sarin, soman, tabun and VX, are extremely neurotoxic organophosphorus compounds. Catalytic bioscavengers capable of hydrolyzing OPNAs are under development because of the low protective effects and adverse side effects of chemical antidotes to OPNA poisoning. However, these bioscavengers have certain limitations for practical application, including low catalytic activity and narrow specificity. In this study, we generated a fusion-hybrid form of engineered recombinant human paraoxonase 1 (rePON1) and bacterial organophosphorus hydrolase (OPH), referred to as GV-hybrids, using a flexible linker to develop more promising catalytic bioscavengers against a broad range of OPNAs. These GV-hybrids were able to synergistically hydrolyze both G-type OPNA analogs (paraoxon: 1.7 ~ 193.7-fold, p-nitrophenyl diphenyl phosphate (PNPDPP): 2.3 ~ 33.0-fold and diisopropyl fluorophosphates (DFP): 1.4 ~ 22.8-fold) and V-type OPNA analogs (demeton-S-methyl (DSM): 1.9 ~ 34.6-fold and malathion: 1.1 ~ 4.2-fold above) better than their individual enzyme forms. Among the GV-hybrid clones, the GV7 clone showed remarkable improvements in the catalytic activity toward both G-type OPNA analogs (kcat/Km (106 M-1 min-1): 59.8 ± 0.06 (paraoxon), 5.2 ± 0.02 (PNPDPP) and 47.0 ± 6.0 (DFP)) and V-type OPNA analogs (kcat/Km (M-1 min-1): 504.3 ± 48.5 (DSM) and 1324.0 ± 47.5 (malathion)). In conclusion, we developed GV-hybrid forms of rePON1 and bacterial OPH mutants as effective and suitable catalytic bioscavengers to hydrolyze a broad range of OPNA analogs.

• Journal of The Korean Society of Grassland and Forage Science
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• v.28 no.3
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• pp.193-202
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• 2008

In Korea, domestic consumption of barley as a cereal crop has been decreasing since the 1980s. It has been considered that winter-season crop production could enhance the global competitiveness of domestic livestock industry by providing better quality fodder to livestock and enhancing field use rate. Therefore, the purpose of barley cultivation for cereal food production has been recently replaced by the production of forage barley. Consequently, the area of barley cultivation for forage is markedly increasing in Korea. Forage barley is cultivars especially as forage for cattle. While any type of barley can be used as forage for feeding cattle, forage barleys deliver a higher dry matter yield than conventional feed barley. We have developed forage barley cultivars with cattle's favorite characters such as smooth awn, hood and auricleless types. Cultivar Wooho, Yuyeon, and Dami have smooth awn, hood type spike, and auricleless type plant. We also developed rough awn type barley cultivars, such as Yongyang, Sunwoo, Sangweon, and Soman, showing earlymaturing and high-yielding. They showed about 12 to 10 ton ha－1 in dry matter yield (average 33 ton $ha^{-1}$ in fresh matter yield). And these were evaluated by forage quality which showed a higher grade of silage quality (TDN, ADF, NDF, CP, etc.) for whole crop barley use. Based on these results, it indicated that barley with smooth awn, hooded, and auricleless could be suitable sources in breeding for whole crop forage use.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.4
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• pp.458-463
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• 2015

This study was conducted to investigate the mixed seeding of 5 forage barley varieties (youngyang, yuyeon, dami, wooho, soman) with 1 malting barley variety (hopum). Yield of the mixed seeding was compared with each single seeding and variety combinations. Yield of mixed seeding combination was higher than each single seeding. In mixed seeding of 'Youngyang' and 'Hopum' (50% and 50% ratio), 'Yuyeon' and 'Hopum' (70% and 30% ratio), 'Dami' and 'Hopum' (50% and 50% ratio), 'Wooho' and 'Hopum' (50% and 50% ratio) were higher yield of dry weight than yield of other mixed ratios. Most of all, mixed seeding of 'Dami' and 'Hopum' were high yield mixed seeding (ratios of 50% each other). In generally, the yields of barley mixed seeding with malting barley 'Hopum' were high production. The forage quality of mixed seeding combination was higher than any each single seeding. 'Youyeon' 50% and 'Hopum' 50% ratio was more higher TDN content (69.2%) than any other mixed combination.