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Jasminum sambac is a well-known plant for its attractive and exceptional fragrance, the flowers of which are used to produce scented tea. Jasmonate (JA), an important plant hormone was first identified in Jasminum species. Jasmine plants contain abundant JA naturally, of which the molecular mechanisms of synthesis and accumulation are not clearly understood. Here, we report a telomere-to-telomere consensus assembly of a double-petal J. sambac genome along with two haplotype-resolved genomes. We found that gain-and-loss, positive selection, and allelic specific expression of aromatic volatile-related genes contributed to the stronger flower fragrance in double-petal J. sambac compared with single- and multi-petal jasmines. Through comprehensive comparative genomic, transcriptomic, and metabolomic analyses of double-petal J. sambac, we revealed the genetic basis of the production of aromatic volatiles and salicylic acid (SA), and the accumulation of JA under non-stress conditions. We identified several key genes associated with JA biosynthesis, and their non-stress related activities lead to extraordinarily high concentrations of JA in tissues. High JA synthesis coupled with low degradation in J. sambac results in accumulation of high JA under typical environmental conditions, similar to the accumulation mechanism of SA. This study offers important insights into the biology of J. sambac, and provides valuable genomic resources for further utilization of natural products.

Free and glycosidically bound volatiles are two essential aroma compounds contributing to the flavour of nectarine fruits. To explore the relationship between free and bound volatiles in nectarine fruits during postharvest storage, they were first harvested and then subjected to the temperatures of 1, 5, and 8°C for 35 d, and the changes in volatile compounds, β-glucosidase (β-Glu) activity, and the expression of UGT (UDP-glucosyltransferase) involved in the accumulation of bound linalool were determined. Results showed that nectarine fruits stored at 5°C had the lowest contents of free volatile compounds due to damage from chilling injury, and the contents of esters and lactones decreased at 1 and 5°C. The contents of bound volatiles increased during the early storage period, and decreased afterwards due to an increase in β-Glu activity. Corresponding to the higher contents of bound volatiles at 1°C, the β-Glu activity in nectarine fruits stored at 1°C was significantly lower than that in nectarine fruits stored at the other two temperatures.

Intestinal farnesoid X receptor (FXR) plays a critical role in alcohol-associated liver disease (ALD). We aimed to investigate whether alcohol-induced dysbiosis increased intestinal microRNA194 (miR194) that suppressed Fxr transcription and whether Lactobacillus rhamnosus GG-derived exosome-like nanoparticles (LDNPs) protected against ALD through regulation of intestinal miR194-FXR signaling in mice.Binge-on-chronic alcohol exposure mouse model was utilized. In addition to the decreased ligand-mediated FXR activation, alcohol feeding repressed intestinal Fxr transcription and increased miR194 expression. This transcriptional suppression of Fxr by miR194 was confirmed in intestinal epithelial Caco-2 cells and mouse enteriods. The alcohol feeding-reduced intestinal FXR activation was further demonstrated by the reduced FXR reporter activity in fecal samples and by the decreased fibroblast growth factor 15 (Fgf15) messenger RNA (mRNA) in intestine and protein levels in the serum, which caused an increased hepatic bile acid synthesis and lipogeneses. We further demonstrated that alcohol feeding increased-miR194 expression was mediated by taurine-upregulated gene 1 (Tug1) through gut microbiota regulation of taurine metabolism. Importantly, 3-day oral administration of LDNPs increased bile salt hydrolase (BSH)-harboring bacteria that decreased conjugated bile acids and increased gut taurine concentration, which upregulated Tug1, leading to a suppression of intestinal miR194 expression and recovery of FXR activation. Activated FXR upregulated FGF15 signaling and subsequently reduced hepatic bile acid synthesis and lipogenesis and attenuated ALD. These protective effects of LDNPs were eliminated in intestinal FxrOur results demonstrated that gut microbiota-mediated miR194 regulation contributes to ALD pathogenesis and to the protective effects of LDNPs through modulating intestinal FXR signaling.

The wax apple (Syzygium samarangense) is an economically important fruit crop with great potential value to human health because it has rich antioxidant substances. Here, we presented one haplotype-resolved autotetraploid genome assembly of the wax apple with size of 1.59 Gb. Comparative genomic analysis revealed three rounds of whole-genome duplication (WGD) events, including two independent WGDs after WGT-γ. Resequencing analysis of 35 accessions partitioned these individuals into two distinct groups, including 28 landraces and seven cultivated species, and several selectively swept genes possibly contributed to fruit growth, includingKRP1-like, IAA17-like, GME-like, andFLACCA-likegenes. Transcriptome analysis in three different varieties during flower and fruit development identified key genes related to fruit size, sugar content, and male sterility. We foundAP2also affects the fruit size by regulating the sepal development in wax apples. The expression of sugar transport-related genes (SWEETs andSUTs) was high in ‘ZY’, likely contributing to a high level of sugar content. Male sterility in ‘Tub’ was associated with tapetal abnormalities due to the decreased expression ofDYT1, TDF1, andAMS, which affects the early tapetum development. The chromosome-scale genome and large-scale transcriptome data presented in this study offer new valuable resources for biological research onS. samarangense, and sheds new light on fruit size control, sugar metabolism, and male sterility regulatory metabolism in wax apple.

The lemon (Citrus limon; family Rutaceae) is one of the most important and popular fruits worldwide. Lemon also tolerates huanglongbing (HLB) disease, which is a devastating citrus disease. Here we produced a gap-free and haplotype-resolved chromosome-scale genome assembly of the lemon by combining Pacific Biosciences circular consensus sequencing, Oxford Nanopore 50-kb ultra-long, and high-throughput chromatin conformation capture technologies. The assembly contained nine-pair chromosomes with a contig N50 of 35.6 Mb and zero gaps, while a total of 633.0 Mb genomic sequences were generated. The origination analysis identified 338.5 Mb genomic sequences originating from citron (53.5%), 147.4 Mb from mandarin (23.3%), and 147.1 Mb from pummelo (23.2%). The genome included 30 528 protein-coding genes, and most of the assembled sequences were found to be repetitive sequences. Several significantly expanded gene families were associated with plant–pathogen interactions, plant hormone signal transduction, and the biosynthesis of major active components, such as terpenoids and flavor compounds. Most HLB-tolerant genes were expanded in the lemon genome, such as 2-oxoglutarate (2OG)/Fe(II)-dependent oxygenase and constitutive disease resistance 1, cell wall-related genes, and lignin synthesis genes. Comparative transcriptomic analysis showed that phloem regeneration and lower levels of phloem plugging are the elements that contribute to HLB tolerance in lemon. Our results provide insight into lemon genome evolution, active component biosynthesis, and genes associated with HLB tolerance.

Antimicrobial resistance-related infections of Gram-negative pathogens pose a huge threat to global public health. Lysins, peptidoglycan hydrolases from bacteriophages, are expected as an alternative weapon against drug-resistant bacteria. In the present study, we report a new lysin LysP53 from Acinetobacter baumannii phage 53. Bioinformatic analysis revealed that LysP53 contains a positively charged N-terminal region and a putative peptidase catalytic domain. In vitro biochemical experiments showed that LysP53 is active against multiple antibiotic-resistant Gram-negative bacteria, including A. baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli, with a reduction of 5 logs in viable A. baumannii number after exposure to 100 μg/mL LysP53 for 1 h. Further studies showed that LysP53 contains a functional antimicrobial peptide, i.e., N-terminal 33 aa, with a comparable spectrum of activity to LysP53. In an A. baumannii-associated mouse model of burn infection, a single dose of 14 μg/mouse LysP53 (57.6 μM) showed higher decolonization efficacy than 4 μg/mouse minocycline- (874 μM; p < 0.05) and buffer-treated groups (p

Alcohol‐associated liver disease (ALD) is a major cause of mortality. Gut barrier dysfunction–induced bacterial translocation and endotoxin release contribute to the pathogenesis of ALD. Probiotic Lactobacillus rhamnosus GG (LGG) is known to be beneficial on experimental ALD by reinforcing the intestinal barrier function. In this study, we aim to investigate whether the protective effects of LGG on intestinal barrier function is mediated by exosome‐like nanoparticles (ELNPs) released by LGG. Intestinal epithelial cells and macrophages were treated with LGG‐derived ELNPs (LDNPs) isolated from LGG culture. LDNPs increased tight junction protein expression in epithelial cells and protected from the lipopolysaccharide‐induced inflammatory response in macrophages. Three‐day oral application of LDNPs protected the intestine from alcohol‐induced barrier dysfunction and the liver from steatosis and injury in an animal model of ALD. Co‐administration of an aryl hydrocarbon receptor (AhR) inhibitor abolished the protective effects of LDNPs, indicating that the effects are mediated, at least in part, by intestinal AhR signaling. We further demonstrated that LDNP administration increased intestinal interleukin‐22‐Reg3 and nuclear factor erythroid 2‐related factor 2 (Nrf2)–tight junction signaling pathways, leading to the inhibition of bacterial translocation and endotoxin release in ALD mice. This protective effect was associated with LDNP enrichment of bacterial tryptophan metabolites that are AhR agonists. Conclusions: Our results suggest that the beneficial effects of LGG and their supernatant in ALD are likely mediated by bacterial AhR ligand–enriched LDNPs that increase Reg3 and Nrf2 expression, leading to the improved barrier function. These findings provide a strategy for the treatment of ALD and other gut barrier dysfunction–associated diseases.

Jasminum sambac is a well-known plant for its attractive and exceptional flower fragrance, and the flowers are used to produce scented tea. Jasmonate (JA), an important plant hormone was first identified in Jasminum species. Jasmine plants contain abundant JA naturally, of which the molecular mechanisms of synthesis and accumulation are not clearly understood. Here, we report a telomere-to-telomere consensus assembly of double-petal J. sambac genome along with two haplotype-resolved genomes. We found that gain-and-loss, positive selection, and allelic specific expression of aromatic votatile related genes contributed to the stronger flower fragrance in double-petal J. sambac compared with single- and multi-petal jasmines. Through comprehensive comparative genomic, transcriptomic, and metabolomic analyses of double-petal J. sambac, we revealed the genetic basis of the production of aromatic volatiles, salicylic acid (SA) and the accumulation of JA under non-stress conditions. We identified several key genes associated with JA biosynthesis, and their non-stress related activities lead to extraordinarily high concentrations of JA in tissues. High JA synthesis coupled with low degradation in J. sambac results in the accumulation of plentiful JA under typical environmental conditions, similar accumulation mechanism of SA. This study offers important insights into the biology of J. sambac, and provides valuable genomic resources for further utilization of natural products.

In this work, a single integrating sphere system was applied to characterize the optical absorption (μ

Alcoholic liver disease (ALD) is associated with gut dysbiosis and hepatic inflammasome activation. While it is known that antimicrobial peptides (AMPs) play a critical role in the regulation of bacterial homeostasis in ALD, the functional role of AMPs in the alcohol-induced inflammasome activation is unclear. The aim of this study was to determine the effects of cathelicidin-related antimicrobial peptide (CRAMP) on inflammasome activation in ALD. CRAMP knockout (Camp-/-) and wild-type (WT) mice were subjected to binge-on-chronic alcohol feeding and synthetic CRAMP peptide was administered. Serum/plasma and hepatic tissue samples from human subjects with alcohol use disorder and/or alcoholic hepatitis were analyzed. CRAMP deficiency exacerbated ALD with enhanced inflammasome activation as shown by elevated serum interleukin (IL)-1β levels. Although Camp-/- mice had comparable serum endotoxin levels compared to WT mice after alcohol feeding, hepatic lipopolysaccharide (LPS) binding protein (LBP) and cluster of differentiation (CD) 14 were increased. Serum levels of uric acid (UA), a Signal 2 molecule in inflammasome activation, were positively correlated with serum levels of IL-1β in alcohol use disorder patients with ALD and were increased in Camp-/- mice fed alcohol. In vitro studies showed that CRAMP peptide inhibited LPS binding to macrophages and inflammasome activation stimulated by a combination of LPS and UA. Synthetic CRAMP peptide administration decreased serum UA and IL-1β concentrations and rescued the liver from alcohol-induced damage in both WT and Camp-/- mice. In summary, CRAMP exhibited a protective role against binge-on-chronic alcohol-induced liver damage via regulation of inflammasome activation by decreasing LPS binding and UA production. CRAMP administration may represent a novel strategy for treating ALD. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Specialized metabolites not only play important roles in biotic and abiotic stress adaptation of tea plants (Camellia sinensis (L.) O. Kuntze) but also contribute to the unique flavor of tea, the most important nonalcoholic beverage. However, the molecular networks and major genes that regulate specialized metabolites in tea plants are not well understood. Here, we constructed a population-level pan-transcriptome of the tea plant leaf using second-leaf transcriptome data from 134 accessions to investigate global expression differences in the population, expression presence or absence variations (ePAVs), and differentially expressed genes (DEGs) between pure Camellia sinensis var. assamica (CSA) and pure Camellia sinensis var. sinensis (CSS) accessions. Next, we used a genome-wide association study, a quantitative trait transcript study, and a transcriptome-wide association study to integrate genotypes, accumulation levels of specialized metabolites, and expression levels of pan-transcriptome genes to identify candidate regulatory genes for flavor-related metabolites and to construct a regulatory network for specialized metabolites in tea plants. The pan-transcriptome contains 30 482 expressed genes, 4940 and 5506 of which were newly annotated from a de novo transcriptome assembly without a reference and a genome reference-based assembly, respectively. DEGs and ePAVs indicated that CSA and CSS were clearly differentiated at the population transcriptome level, and they were closely related to abiotic tolerance and secondary metabolite synthesis phenotypes of CSA and CSS based on gene annotations. The regulatory network contained 212 specialized metabolites, 3843 candidate genes, and 3407 eQTLs, highlighting many pleiotropic candidate genes, candidate gene-rich eQTLs, and potential regulators of specialized metabolites. These included important transcription factors in the AP2/ERF-ERF, MYB, WD40, and bHLH families. CsTGY14G0001296, an ortholog of AtANS, appeared to be directly related to variation in proanthocyanins in the tea plant population, and the CsTGY11G0002074 gene encoding F3′5′H was found to contribute to the biased distribution of catechins between pure CSAs and pure CSSs. Together, these results provide a new understanding of the metabolite diversity in tea plants and offer new insights for more effective breeding of better-flavored tea varieties.

Antimicrobial resistance-related infections of Gram-negative pathogens pose a huge threat to global public health. Lysins, peptidoglycan hydrolases from bacteriophages, are expected as an alternative weapon against drug-resistant bacteria. In the present study, we report a new lysin LysP53 from

Alcohol consumption and obesity are known risk factors of steatohepatitis. Here, we report that the deficiency of CRAMP (cathelicidin-related antimicrobial peptide—gene name: Camp) is protective against a high-fat diet (HFD) plus acute alcohol (HFDE)-induced liver injury. HFDE markedly induced liver injury and steatosis in WT mice, which were attenuated in Camp–/– mice. Neutrophil infiltration was lessened in the liver of Camp–/– mice. HFDE feeding dramatically increased epididymal white adipose tissue (eWAT) mass and induced adipocyte hypertrophy in WT mice, whereas these effects were attenuated by the deletion of Camp. Furthermore, Camp–/– mice had significantly increased eWAT lipolysis, evidenced by up-regulated expression of lipolytic enzymes, adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL). The depletion of Camp also increased uncoupling protein 1 (UCP1)-dependent thermogenesis in the brown adipose tissue (BAT) of mice. HFDE fed Camp–/– mice had elevated protein levels of fibroblast growth factor 21 (FGF21) in the eWAT, with an increased adiponectin production, which had been shown to alleviate hepatic fat deposition and inflammation. Collectively, we have demonstrated that Camp–/– mice are protected against HFD plus alcohol-induced liver injury and steatosis through FGF21/adiponectin regulation. Targeting CRAMP could be an effective approach for prevention/treatment of high-fat diet plus alcohol consumption-induced steatohepatitis.

To obtain a novel multifunctional flame retardant material, Triphenyl phosphate (TPP) was used as the capsule material to microencapsulate diatomite/ammonium polyphosphate (Dia/APP). The novel multifunctional material Dia-APP-TPP could effectively improve the flame retardancy of unsaturated polyester resin (UPR). The desired structure of Dia-APP-TPP was clearly observed through Fourier Transform Infrared (FTIR), X-ray Photoelectron Spectroscopy (XPS) and Scanning electron microscopy (SEM). The combustion behavior, thermal property and mechanical performance of UPR/Dia-APP-TPP composites were also investigated. Incorporation of Dia-APP-TPP into UPR greatly enhanced the flame retardancy and thermal stability of the composites. Remarkably, with 20 wt% of Dia-APP-TPP, UPR-2 successfully achieved UL-94 V-0 rating and the LOI value increased from 19.2% to 26.6%. Besides, the CCT test showed that the THR value of UPR-2 decreased by 33.9% compared with that of pure UPR. The results of this study also confirmed that a novel and feasible strategy can be used to obtain a microencapsulation flame retardant.

African swine fever (ASF) is a highly contagious viral disease of domestic pigs and wild boars. For disease surveillance and control, we developed a rapid and easy luciferase immunoprecipitation assay (MB-LIPS) to detect ASF virus (ASFV) antibody. The MB-LIPS is based on magnetic beads modified with protein A/G and the recombinant fusion protein of ASFV p30 and luciferase, where p30 functioned as the recognition element and luciferase as the signal component. Incubation and washing could be finished automatically on a machine with magnetic rods. Under optimal conditions, the MB-LIPS showed 96.3% agreement to a commercial enzyme-linked immunosorbent assay (ELISA) kit for detecting ASFV antibody in swine sera. Analyzing serial dilutions of a swine serum sample showed that the MP-LIPS assay was 4 times more sensitive than the ELISA kit. The whole run of the MB-LIPS could be completed within 30 min. With its high sensitivity and simple operation, the MB-LIPS platform has great potential to be used for the detection of ASFV antibody and ASF control in small labs and farms.

The rapid spread and emergence of multidrug-resistant Acinetobacter baumannii and other pathogenic Gram-negative bacteria spurred scientists and clinicians to look for alternative therapeutic agents to conventional antibiotics. In the present study, an A. baumannii bacteriophage p54 was isolated and characterized. Morphological and genome analysis revealed that bacteriophage p54 belongs to Myoviridae family with a genome size of 165,813 bps. A novel endolysin, namely LysAB54, showing low similarity with other well-known related endolysins, was cloned, expressed, and characterized from the bacteriophage p54. LysAB54 showed significant bactericidal activity against multidrug-resistant A. baumannii and other Gram-negative bacteria, including Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli, in the absence of outer membrane permeabilizers. Based on all those observations, LysAB54 could represent a potential agent for the treatment of multidrug-resistant Gram-negative superbugs.

In the present study, we developed a phage-based real-time quantitative PCR (qPCR ) methodology for sensitive diagnosis of bloodstream infection (BSI) caused by Acinetobacter baumannii (A. baumannii). An isolated A. baumannii phage p53 was used for Taqman qPCR through detecting phage replication in live A. baumannii cells in serum samples. At the phage concentration of 103 PFU/mL, the sensitive detection of A. baumannii (down to 10 CFU in 100 μL serum) has been obtained within 4 h in spiked serum samples without bacteria isolation and DNA extraction. Subsequent testing of 22 simulated serum samples spiked by different strains has shown that the results from the phage-based Taqman qPCR method have 100% agreement with the spiked concentrations of the bacteria. The assay built in this study, gathering all the advantages for detections of high rapidity, high sensitivity, good specificity, being able to detect only live bacteria not dead bacteria and no DNA extraction or purifications, can be developed to detecting other bacterial pathogens in serum or other complicated samples through switching to other types of phages and realize the rapid and sensitive detection of bacteria in BSI, which would potentially be applied for fast diagnosis in sepsis clinically.

A series of flame-retardant unsaturated polyester resin (UPR) were prepared by the addition of dimethyl methylphosphonate (DMMP) with various amounts of aluminum hydroxide (ATH) or ammonium polyphosphate (APP) as the flame retardants. The combustion resistance effects of ATH/DMMP and APP/DMMP systems were evaluated by limiting oxygen index test and vertical burning test (UL-94). The thermal properties of UPR were investigated by thermogravimetric analysis. The structure of char was observed by scanning electron microscopy. DMMP incorporated with ATH or APP improved the flame retardancy and thermal properties of UPR. However, the fire-retardant mechanism of these two systems were different: The ATH/DMMP system provided synergistic effect in charring property of the UPR, produced great amount of residual char, and thus revealed the excellent flame retardancy. The APP/DMMP system further improved the flame retardancy of the UPR due to the change in the residual char structure rather than the increase...

Background Accurate and rapid identification of ventilator associated or nosocomial pneumonia caused by Acinetobacter baumannii ( A. baumannii ) could improve the treatment.Methods In current study, we developed a phage-based real-time quantitative PCR (qPCR) combined with enrichment culture for rapid and specific detection of viable A. baumannii in sputum from lung infections. Through short-term plate incubation, bacteria can be enriched and the DNA polymerase reaction disturbance of sputum can be decreased greatly. This approach is based on detecting phage replication in live A. baumannii cells through Taqman qPCR.Results Through the built detection system, down to 1 CFU of A. baumannii can be detected within 6 h in spiked sputum samples without any steps of bacteria isolation and DNA extraction. The established method was then applied to detecting both A. baumannii in simulated sputum with 100% agreement with the spiked amount of the bacteria and one clinical sputum sample from an 80-year-old male lung infection patient caused by A. baumannii with perfect accuracy, demonstrating that the assay developed in this study has the merits of high rapidity, high sensitivity, good specificity and being able to detect live bacteria not dead bacteria.Conclusions The assay is a potentially clinical method for diagnosis of bacterial pneumonia infection caused by A. baumannii or other bacterial infection in sputum or complicated samples through switching to other types of phages.

Background and aims Cholestatic liver disease is characterized by gut dysbiosis and excessive toxic hepatic bile acids (BAs). Modification of gut microbiota and repression of BA synthesis are potential strategies for the treatment of cholestatic liver disease. The purpose of this study was to examine the effects and to understand the mechanisms of the probiotic Lactobacillus rhamnosus GG (LGG) on hepatic BA synthesis, liver injury, and fibrosis in bile duct ligation (BDL) and multidrug resistance protein 2 knockout (Mdr2-/- ) mice. Approach and results Global and intestine-specific farnesoid X receptor (FXR) inhibitors were used to dissect the role of FXR. LGG treatment significantly attenuated liver inflammation, injury, and fibrosis with a significant reduction of hepatic BAs in BDL mice. Hepatic concentration of taurine-β-muricholic acid (T-βMCA), an FXR antagonist, was markedly increased in BDL mice and reduced in LGG-treated mice, while chenodeoxycholic acid, an FXR agonist, was decreased in BDL mice and normalized in LGG-treated mice. LGG treatment significantly increased the expression of serum and ileum fibroblast growth factor 15 (FGF-15) and subsequently reduced hepatic cholesterol 7α-hydroxylase and BA synthesis in BDL and Mdr2-/- mice. At the molecular level, these changes were reversed by global and intestine-specific FXR inhibitors in BDL mice. In addition, LGG treatment altered gut microbiota, which was associated with increased BA deconjugation and increased fecal and urine BA excretion in both BDL and Mdr2-/- mice. In vitro studies showed that LGG suppressed the inhibitory effect of T-βMCA on FXR and FGF-19 expression in Caco-2 cells. Conclusion LGG supplementation decreases hepatic BA by increasing intestinal FXR-FGF-15 signaling pathway-mediated suppression of BA de novo synthesis and enhances BA excretion, which prevents excessive BA-induced liver injury and fibrosis in mice.

Melamine cyanurate (MCA) and triphenyl phosphate (TPP) were added in unsaturated polyester resin (UPR) and the combustion behaviour were investigated. Flame retardant and thermal stability were investigated through limiting oxygen index test (LOI), vertical burning test (UL-94) and thermogravimetric analysis (TGA). The scanning electron microscopy (SEM) and TGA analyses showed that the char yield was increased by the introduction of MCA and TPP system. Therefore, a profound flame retardant effect was obtained as MCA and TPP were added to UPR.