본 실험은 마이크로웨이브 처리가 상추 유묘의 생육 변화와 이차대사산물 함량의 변화를 알아보고자 수행되었다. 파종 후 3주째 상추 유묘에 2.45GHz 주파수와 200W의 마이크로 웨이브를 0, 4, 8 및 12초 동안 처리하고, 4주간 식물공장에서 재배한 후 생육 및 성분 분석을 수행하였다. 지하부와 지상부 의 생체중과 건물중, 엽면적, 엽장 및 엽수는 마이크로웨이브 처리시간이 증가할수록 감소하였다. 4초 처리구와 비교하여 12초 처리구에서 chlorophyll a, chlorophyll b 및 총 carotenoids 의 함량이 증가되었으며 총 페놀 함량은 감소하였다. 무처리 구와 비교하여 8초 처리구에서 총 플라보노이드 함량이 감소 하였다. 이러한 결과들은 산화적 스트레스에 의해 이차대사 산물 함량이 변화된 것으로 사료된다. 총 플라보노이드 함량 을 제외한 이차대사산물 함량은 각 처리구에서 무처리구와 비 교하여 유의한 차이가 없었지만, 각 처리구 사이의 유의한 차 이는 200W와 2.45GHz의 마이크로웨이브 처리가 4주 후 상 추의 이차대사산물 함량에 영향을 줄 수 있다는 것을 시사한다.
We investigated the detoxification strategies of Helicoverpa armigera and Heliothis virescens, which allow them to feed successfully on cotton plants that produce toxic gossypol as a chemical defense compound. First, we tested CYP6AE14, a proposed candidate enzyme for gossypol detoxification, for its ability to detoxify gossypol. In incubation assays with gossypol and heterologously expressed CYP6AE14 no metabolites were detected. Our data show that CYP6AE14 is not directly involved in gossypol metabolism, at least under the assay conditions tested, but rather takes part in the general stress response of the herbivores to plant toxins. Second, we discovered that H. armigera and H. virescens excrete a large proportion (50%) of unmetabolized gossypol in the feces, but additionally metabolize gossypol by glycosylation. Analysis of larval feces revealed three monoglycosylated and up to five diglycosylated gossypol isomers when larvae fed on gossypol-supplemented diet. Based on their expression patterns we selected H. armigera candidate UGT genes and functionally expressed the respective proteins in insect cells. In enzymatic assays, we showed that UGT41B3 and UGT40D1 are capable of glycosylating gossypol mainly to a diglycosylated gossypol isomer that is characteristic for H. armigera and is absent in H. virescens feces. We offer novel insights into the detoxification mechanism of the plant defensive toxin, gossypol, by two generalist herbivores.
Isaria farinosa (Hypocreales, Ascomycota) is a cosmopolitan entomopathogenic fungus affecting a wide range of arthropod hosts. It has mainly been studied as a insecticidal agent to control the agricultural pests. To investigate the useful secondary metabolite(SM) genes in Isaria farinosa C1012 strain, de novo assembly and genome mining were carried out. A whole genome sequencing with PacBio RSII system generated NGS reads greater than 4Gb, which were assembled into 16 contigs using FALCON program. The total size of genome was 33.36Mb. The N50 and N90 were 6,686,213 and 1,912,865bp, respectively. The assembled genome data was analyzed with antiSMASH3 program with a default setting to localize the gene region responsible for synthesizing SMs, such as non-ribosomal peptide synthetases (NRPS) and polyketide synthase (PKS). In this study, we predicted 16 NRPS, 13 PKS, and 9 PKS-NRPS hybrid gene clusters in I. farinosa genome.