http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Ting Lei,Suping Gao,Xiao Lin,Kaihui Zhang,Yingqi Liu,Wenji Li,Di Hu,Xiaofang Yu,Mingyan Jiang,Qibing Chen,Ying Sun 한국원예학회 2021 Horticulture, Environment, and Biotechnology Vol.62 No.2
This study selected Dendrobium offi cinale protocorms as the experimental material and used diff erent light-quality treatmentsand calcium signalling inhibitors to explore the mechanism of the biological response of calcium to light quality. The results indicate that a 1:3 red:blue (R:B) light ratio promotes the accumulation of biomass and polysaccharides in theprotocorm. Nevertheless, this eff ect can be entirely counteracted by calmodulin (CaM) inhibitors and calcium ion-chelatingagents. The possible mechanisms of this eff ect are as follows: (1) The Ca 2+ -CaM signal-regulated photosynthetic apparatusis improved by the R:B 1:3 light, increasing the CaM content and Ca 2+ -ATPase activity. Thus, R:B 1:3 light increases thedevelopment of the photosynthetic apparatus in the D. offi cinale protocorm, enhances its photosynthetic productivity, andpromotes the activities of sucrose phosphatase; accordingly, biomass and sucrose accumulation increase. (2) R:B 1:3 lightenhances Ca 2+ -CaM signalling and regulates glycometabolic processes to promote the activities of sucrose synthase, thusincreasing fructose and glucose levels and providing suffi cient synthetic precursors to promote polysaccharide production.
( Wensong Jin ),( Hui Lin ),( Huifang Gao ),( Zewang Guo ),( Jiahuan Li ),( Quanming Xu ),( Shujing Sun ),( Kaihui Hu ),( Jung-kul Lee ),( Liaoyuan Zhang ) 한국미생물생명공학회(구 한국산업미생물학회) 2019 Journal of microbiology and biotechnology Vol.29 No.4
N-acyl-homoserine lactone quorum sensing (AHL-QS) has been shown to regulate many physiological behaviors in Serratia marcescens MG1. In the current study, the effects of AHL-QS on the biosynthesis of acid and neutral products by S. marcescens MG1 and its isogenic ΔswrI with or without supplementing exogenous N-hexanoyl-L-homoserine lactone (C<sub>6</sub>-HSL) were systematically investigated. The results showed that swrI disruption resulted in rapid pH drops from 7.0 to 4.8, which could be restored to wild type by supplementing C<sub>6</sub>-HSL. Furthermore, fermentation product analysis indicated that ΔswrI could lead to obvious accumulation for acidogenesis products such as lactic acid and succinic acid, especially excess acetic acid (2.27 g/l) produced at the early stage of fermentation, whereas solventogenesis products by ΔswrI appeared to noticeably decrease by an approximate 30% for acetoin during 32-48 h and by an approximate 20% for 2,3-butanediol during 24-40 h, when compared to those by wild type. Interestingly, the excess acetic acid produced could be removed in an AHL-QS-independent manner. Subsequently, quantitative real-time PCR was used to determine the mRNA expression levels of genes responsible for acidogenesis and solventogenesis and showed consistent results with those of product synthesis. Finally, by close examination of promoter regions of the analyzed genes, four putative luxI box-like motifs were found upstream of genes encoding acetyl-CoA synthase, lactate dehydrogenase, α-acetolactate decarboxylase, and Lys-like regulator. The information from this study provides a novel insight into the roles played by AHL-QS in switching from acidogenesis to solventogenesis in S. marcescens MG1.