scholarly journals Identification and Characterization of Chalcone Isomerase Genes Involved in Flavonoid Production in Dracaena cambodiana

2021 ◽  
Vol 12 ◽  
Author(s):  
Jiahong Zhu ◽  
Wan Zhao ◽  
Rongshuang Li ◽  
Dong Guo ◽  
Huiliang Li ◽  
...  
Keyword(s):  
Transcriptional Profiling ◽  
Normal Growth ◽  
Growth Conditions ◽  
Ultraviolet B ◽  
Chalcone Isomerase ◽  
Enzyme Activity Assay ◽  
Dragon’S Blood ◽  
Dracaena Cambodiana ◽  
Key Enzyme

Dragon’s blood is a traditional medicine in which flavonoids are the main bioactive compounds; however, the underlying formation mechanism of dragon’s blood remains largely poorly understood. Chalcone isomerase (CHI) is the key enzyme in the flavonoid biosynthesis pathway. However, CHI family genes are not well understood in Dracaena cambodiana Pierre ex Gagnep, an important source plant of dragon’s blood. In this study, 11 CHI family genes were identified from D. cambodiana, and they were classified into three types. Evolutionary and transcriptional profiling analysis revealed that DcCHI1 and DcCHI4 might be involved in flavonoid production. Both DcCHI1 and DcCHI4 displayed low expression levels in stem under normal growth conditions and were induced by methyl jasmonate (MeJA), 6-benzyl aminopurine (6-BA, synthetic cytokinin), ultraviolet-B (UV-B), and wounding. The recombinant proteins DcCHI1 and DcCHI4 were expressed in Escherichia coli and purified by His-Bind resin chromatography. Enzyme activity assay indicated that DcCHI1 catalyzed the formation of naringenin from naringenin chalcone, while DcCHI4 lacked this catalytic activity. Overexpression of DcCHI1 or DcCHI4 enhanced the flavonoid production in D. cambodiana and tobacco. These findings implied that DcCHI1 and DcCHI4 play important roles in flavonoid production. Thus, our study will not only contribute to better understand the function and expression regulation of CHI family genes involved in flavonoid production in D. cambodiana but also lay the foundation for developing the effective inducer of dragon’s blood.

scholarly journals Characterization of the radiation desiccation response regulon of the radioresistant bacterium Deinococcus radiodurans by integrative genomic analyses.

2021 ◽  
Author(s):  
Nicolas Eugenie ◽  
Yvan Zivanovic ◽  
Gaelle Lelandais ◽  
Genevieve Coste ◽  
Claire Bouthier de la Tour ◽  
...  
Keyword(s):  
Deinococcus Radiodurans ◽  
Normal Growth ◽  
Growth Conditions ◽  
Rna Seq ◽  
Genome Wide ◽  
A Genome ◽  
Genomic Analyses ◽  
Number Of Genes ◽  
Wide Scale

Numerous genes are overexpressed in the radioresistant bacterium Deinococcus radiodurans after exposure to radiation or prolonged desiccation. The DdrO and IrrE proteins play a major role in regulating the expression of approximately predicted twenty of these genes. The transcriptional repressor DdrO blocks the expression of these genes under normal growth conditions. After exposure to genotoxic agents, the IrrE metalloprotease cleaves DdrO and relieves gene repression. Bioinformatic analyzes showed that this mechanism seems to be conserved in several species of Deinococcus, but many questions remain as such the number of genes regulated by DdrO. Here, by RNA-seq and CHiP-seq assays performed at a genome-wide scale coupled with bioinformatic analyses, we show that, the DdrO regulon in D. radiodurans includes many other genes than those previously described. These results thus pave the way to better understand the radioresistance mechanisms encoded by this bacterium.

scholarly journals (86) Isolation and Molecular Characterization of Putative Ascorbate Peroxidase from Citrus

HortScience ◽  
2006 ◽  
Vol 41 (4) ◽  
pp. 1021D-1021
Author(s):  
Madhurababu Kunta ◽  
H. Sonia del Rio ◽  
Eliezer Louzada
Keyword(s):  
Ascorbate Peroxidase ◽  
Normal Growth ◽  
Stress Conditions ◽  
Full Length ◽  
Homology Search ◽  
Reading Frame ◽  
Key Enzyme ◽  
Differential Display Reverse Transcription ◽  
Polymerase Chain

Reactive oxygen species (ROS) are continuously produced during the normal aerobic metabolism and also under environmental stress conditions. They are the major damaging factors to the photosynthetic machinery under stress conditions and need to be scavenged for the normal growth of the plant. Ascorbate peroxidase (APX) is the key enzyme in detoxifying H2O2, one of ROS from chloroplast and cytosol. A cDNA encoding a putative APXcit was isolated from mature `Dancy' tangerine (Citrus reticulata Blanco) juice vesicles using differential display reverse transcription-polymerase chain reaction (RT-PCR). Subsequently, full-length APXcit cDNA clone and genomic clone were obtained and sequenced. The full-length APXcit sequence is composed by 1082-bp nucleotides, including an open reading frame (ORF) of 753 bp, encoding a protein of 250 amino acids (27 kDa). The 5' un-translated region (UTR) of the APXcit gene consisted of 91 nucleotides and the 3' UTR consisted of 238 nucleotides. Homology search for APXcit at GenBank database showed high similarity to APX from several plant species.

scholarly journals Characterization of the Radiation Desiccation Response Regulon of the Radioresistant Bacterium Deinococcus radiodurans by Integrative Genomic Analyses

Cells ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2536
Author(s):  
Nicolas Eugénie ◽  
Yvan Zivanovic ◽  
Gaelle Lelandais ◽  
Geneviève Coste ◽  
Claire Bouthier de la Tour ◽  
...  
Keyword(s):  
Deinococcus Radiodurans ◽  
Transcriptional Repressor ◽  
Normal Growth ◽  
Growth Conditions ◽  
Rna Seq ◽  
Dna And Rna ◽  
Genomic Analyses ◽  
Number Of Genes ◽  
Genome Level

Numerous genes are overexpressed in the radioresistant bacterium Deinococcus radiodurans after exposure to radiation or prolonged desiccation. It was shown that the DdrO and IrrE proteins play a major role in regulating the expression of approximately twenty genes. The transcriptional repressor DdrO blocks the expression of these genes under normal growth conditions. After exposure to genotoxic agents, the IrrE metalloprotease cleaves DdrO and relieves gene repression. At present, many questions remain, such as the number of genes regulated by DdrO. Here, we present the first ChIP-seq analysis performed at the genome level in Deinococcus species coupled with RNA-seq, which was achieved in the presence or not of DdrO. We also resequenced our laboratory stock strain of D. radiodurans R1 ATCC 13939 to obtain an accurate reference for read alignments and gene expression quantifications. We highlighted genes that are directly under the control of this transcriptional repressor and showed that the DdrO regulon in D. radiodurans includes numerous other genes than those previously described, including DNA and RNA metabolism proteins. These results thus pave the way to better understand the radioresistance pathways encoded by this bacterium and to compare the stress-induced responses mediated by this pair of proteins in diverse bacteria.

scholarly journals Autophagy-dependent ribosomal RNA degradation is essential for maintaining nucleotide homeostasis during C. elegans development

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Yubing Liu ◽  
Wei Zou ◽  
Peiguo Yang ◽  
Li Wang ◽  
Yan Ma ◽  
...  
Keyword(s):  
Ribosomal Rna ◽  
Ribosomal Proteins ◽  
De Novo ◽  
Normal Growth ◽  
Growth Conditions ◽  
Rna Degradation ◽  
Pyrimidine Nucleotides ◽  
C Elegans ◽  
Key Enzyme ◽  
Simultaneous Loss

Ribosome degradation through the autophagy-lysosome pathway is crucial for cell survival during nutrient starvation, but whether it occurs under normal growth conditions and contributes to animal physiology remains unaddressed. In this study, we identified RNST-2, a C. elegans T2 family endoribonuclease, as the key enzyme that degrades ribosomal RNA in lysosomes. We found that loss of rnst-2 causes accumulation of rRNA and ribosomal proteins in enlarged lysosomes and both phenotypes are suppressed by blocking autophagy, which indicates that RNST-2 mediates autophagic degradation of ribosomal RNA in lysosomes. rnst-2(lf) mutants are defective in embryonic and larval development and are short-lived. Remarkably, simultaneous loss of RNST-2 and de novo synthesis of pyrimidine nucleotides leads to complete embryonic lethality, which is suppressed by supplements of uridine or cytidine. Our study reveals an essential role of autophagy-dependent degradation of ribosomal RNA in maintaining nucleotide homeostasis during animal development.

scholarly journals Characterization of Bacillus anthracis-Like Bacteria Isolated from Wild Great Apes from Côte d'Ivoire and Cameroon

2006 ◽  
Vol 188 (15) ◽  
pp. 5333-5344 ◽  
Author(s):  
Silke R. Klee ◽  
Muhsin Özel ◽  
Bernd Appel ◽  
Christophe Boesch ◽  
Heinz Ellerbrok ◽  
...  
Keyword(s):  
Bacillus Anthracis ◽  
Protective Antigen ◽  
Normal Growth ◽  
Growth Conditions ◽  
Penicillin G ◽  
Molecular Features ◽  
Close Relationship ◽  
Resistance To Penicillin ◽  
Relationship Of

ABSTRACT We present the microbiological and molecular characterization of bacteria isolated from four chimpanzees and one gorilla thought to have died of an anthrax-like disease in Côte d'Ivoire and Cameroon. These isolates differed significantly from classic Bacillus anthracis by the following criteria: motility, resistance to the gamma phage, and, for isolates from Cameroon, resistance to penicillin G. A capsule was expressed not only after induction by CO2 and bicarbonate but also under normal growth conditions. Subcultivation resulted in beta-hemolytic activity and gamma phage susceptibility in some subclones, suggesting differences in gene regulation compared to classic B. anthracis. The isolates from Côte d'Ivoire and Cameroon showed slight differences in their biochemical characteristics and MICs of different antibiotics but were identical in all molecular features and sequences analyzed. PCR and Southern blot analyses confirmed the presence of both the toxin and the capsule plasmid, with sizes corresponding to the B. anthracis virulence plasmids pXO1 and pXO2. Protective antigen was expressed and secreted into the culture supernatant. The isolates possessed variants of the Ba813 marker and the SG-749 fragment differing from that of classic B. anthracis strains. Multilocus sequence typing revealed a close relationship of our atypical isolates with both classic B. anthracis strains and two uncommonly virulent Bacillus cereus and Bacillus thuringiensis isolates. We propose that the newly discovered atypical B. anthracis strains share a common ancestor with classic B. anthracis or that they emerged recently by transfer of the B. anthracis plasmids to a strain of the B. cereus group.

scholarly journals A Novel Bvg-Repressed Promoter Causesvrg-Like Transcription offim3but Does Not Result in the Production of Serotype 3 Fimbriae in Bvg−ModeBordetella pertussis

2018 ◽  
Vol 200 (20) ◽  
Author(s):  
Qing Chen ◽  
Gloria Lee ◽  
Candice Craig ◽  
Victoria Ng ◽  
Paul E. Carlson ◽  
...  
Keyword(s):  
Bordetella Pertussis ◽  
Transcriptional Profiling ◽  
Phase Variation ◽  
Normal Growth ◽  
Growth Conditions ◽  
Anomalous Behavior ◽  
Content Type ◽  
Fimbrial Subunit ◽  
Stable Production ◽  
High Level

ABSTRACTInBordetella pertussis, two serologically distinct fimbriae, FIM2 and FIM3, undergo on/off phase variation independently of each other via variation in the lengths of C stretches in the promoters for their major subunit genes,fim2andfim3. These two promoters are also part of the BvgAS virulence regulon and therefore, if in an on configuration, are activated by phosporylated BvgA (BvgA~P) under normal growth conditions (Bvg+mode) but not in the Bvg−mode, inducible by growth in medium containing MgSO4or other compounds, termed modulators. In theB. pertussisTohama I strain (FIM2+FIM3−), thefim3promoter is in the off state. However, a high level of transcription of thefim3gene is observed in the Bvg−mode. In this study, we provide an explanation for this anomalous behavior by defining a Bvg-repressed promoter (BRP), located approximately 400 bp upstream of the Pfim3transcriptional start. Although transcription of thefim3gene in the Bvg−mode resulted in Fim3 translation, as measured by LacZ translational fusions, no accumulation of Fim3 protein was detectable. We propose that Fim3 protein resulting from translation of mRNA driven by BRP in the Bvg−mode is unstable due to a lack of the fimbrial assembly apparatus encoded by thefimBCgenes, located within thefhaoperon, and therefore is not expressed in the Bvg−mode.IMPORTANCEInBordetella pertussis, the promoter Pfim3-15C for the major fimbrial subunit genefim3is activated by the two-component system BvgAS in the Bvg+mode but not in the Bvg−mode. However, many transcriptional profiling studies have shown thatfim3is transcribed in the Bvg−mode even when Pfim3is in a nonpermissive state (Pfim3-13C), suggesting the presence of a reciprocally regulated element upstream of Pfim3. Here, we provide evidence that BRP is the cause of this anomalous behavior offim3. Although BRP effectsvrg-like transcription offim3in the Bvg−mode, it does not lead to stable production of FIM3 fimbriae, because expression of the chaperone and usher proteins FimB and FimC occurs only in the Bvg+mode.

scholarly journals Protein O-Mannosyltransferases B and C Support Hyphal Development and Differentiation in Aspergillus nidulans

2009 ◽  
Vol 8 (10) ◽  
pp. 1465-1474 ◽  
Author(s):  
Masatoshi Goto ◽  
Yuka Harada ◽  
Takuji Oka ◽  
Sho Matsumoto ◽  
Kaoru Takegawa ◽  
...  
Keyword(s):  
Aspergillus Nidulans ◽  
Morphological Characteristics ◽  
Normal Growth ◽  
Growth Conditions ◽  
Osmotic Stabilizer ◽  
Genes Encoding ◽  
Development And Differentiation ◽  
Encoding Protein ◽  
Slow Growing

ABSTRACT Aspergillus nidulans possesses three pmt genes encoding protein O-d-mannosyltransferases (Pmt). Previously, we reported that PmtA, a member of the PMT2 subfamily, is involved in the proper maintenance of fungal morphology and formation of conidia (T. Oka, T. Hamaguchi, Y. Sameshima, M. Goto, and K. Furukawa, Microbiology 150:1973-1982, 2004). In the present paper, we describe the characterization of the pmtA paralogues pmtB and pmtC. PmtB and PmtC were classified as members of the PMT1 and PMT4 subfamilies, respectively. A pmtB disruptant showed wild-type (wt) colony formation at 30°C but slightly repressed growth at 42°C. Conidiation of the pmtB disruptant was reduced to approximately 50% of that of the wt strain; in addition, hyperbranching of hyphae indicated that PmtB is involved in polarity maintenance. A pmtA and pmtB double disruptant was viable but very slow growing, with morphological characteristics that were cumulative with respect to either single disruptant. Of the three single pmt mutants, the pmtC disruptant showed the highest growth repression; the hyphae were swollen and frequently branched, and the ability to form conidia under normal growth conditions was lost. Recovery from the aberrant hyphal structures occurred in the presence of osmotic stabilizer, implying that PmtC is responsible for the maintenance of cell wall integrity. Osmotic stabilization at 42°C further enabled the pmtC disruptant to form conidiophores and conidia, but they were abnormal and much fewer than those of the wt strain. Apart from the different, abnormal phenotypes, the three pmt disruptants exhibited differences in their sensitivities to antifungal reagents, mannosylation activities, and glycoprotein profiles, indicating that PmtA, PmtB, and PmtC perform unique functions during cell growth.

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