-
Frontiers in Plant Science 2021Flesh firmness of watermelon is an important quality trait for commercial fruit values, including fruit storability, transportability, and shelf life. To date, knowledge...
Flesh firmness of watermelon is an important quality trait for commercial fruit values, including fruit storability, transportability, and shelf life. To date, knowledge of the gene networks underlying this trait is still limited. Herein, we used weighted genes co-expression network analysis (WGCNA) based on correlation and the association of phenotypic data (cell wall contents) with significantly differentially expressed genes between two materials, a near isogeneic line "HWF" (with high average flesh firmness) and inbred line "203Z" (with low average flesh firmness), to identify the gene networks responsible for changes in fruit flesh firmness. We identified three gene modules harboring 354 genes; these gene modules demonstrated significant correlation with water-soluble pectin, cellulose, hemicellulose, and protopectin. Based on intramodular significance, eight genes involved in cell wall biosynthesis and ethylene pathway are identified as hub genes within these modules. Among these genes, two genes, (Cellulose synthase) and (Pectinesterase), were significantly correlated with cellulose ( = 0.83) and protopectin ( = 0.81); three genes, (ERF1), (Cellulose synthase), and (Galactosyltransferase), had a significant correlation with water-soluble pectin ( = 0.91), cellulose ( = 0.9), and protopectin ( = 0.92); and three genes, (ERF2a), (probable glycosyltransferase), and (Xyloglucan endotransglucosylase/hydrolase), were correlated with hemicellulose ( = 0.85), cellulose ( = 0.8), and protopectin ( = 0.8). This study generated important insights of biosynthesis of a cell wall structure and ethylene signaling transduction pathway, the mechanism controlling the flesh firmness changes in watermelon, which provide a significant source to accelerate future functional analysis in watermelon to facilitate crop improvement.
PubMed: 34239519
DOI: 10.3389/fpls.2021.630243 -
Frontiers in Plant Science 2021Arabinogalactan-proteins (AGPs) are members of the hydroxyproline-rich glycoprotein (HRGP) superfamily, a group of highly diverse proteoglycans that are present in the...
Arabinogalactan-proteins (AGPs) are members of the hydroxyproline-rich glycoprotein (HRGP) superfamily, a group of highly diverse proteoglycans that are present in the cell wall, plasma membrane as well as secretions of almost all plants, with important roles in many developmental processes. The role of GALT8 (At1g22015), a Glycosyltransferase-31 (GT31) family member of the Carbohydrate-Active Enzyme database (CAZy), was examined by biochemical characterization and phenotypic analysis of a mutant line. To characterize its catalytic function, GALT8 was heterologously expressed in tobacco leaves and its enzymatic activity tested. GALT8 was shown to be a β-(1,3)-galactosyltransferase (GalT) that catalyzes the synthesis of a β-(1,3)-galactan, similar to the activity of KNS4/UPEX1 (At1g33430), a homologous GT31 member previously shown to have this activity. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) confirmed the products were of 2-6 degree of polymerisation (DP). Previous reporter studies showed that is expressed in the central and synergid cells, from whence the micropylar endosperm originates after the fertilization of the central cell of the ovule. Homozygous mutants have multiple seedling phenotypes including significantly shorter hypocotyls and smaller leaf area compared to wild type (WT) that are attributable to defects in female gametophyte and/or endosperm development. was shown to partially complement the mutant phenotypes in genetic complementation assays suggesting a similar but not identical role compared to in β-(1,3)-galactan biosynthesis. Taken together, these data add further evidence of the important roles GT31 β-(1,3)-GalTs play in elaborating type II AGs that decorate AGPs and pectins, thereby imparting functional consequences on plant growth and development.
PubMed: 34113372
DOI: 10.3389/fpls.2021.678564 -
Food Science and Biotechnology Apr 2021In this study, the physiochemical and antioxidant properties of the soybean hulls from the genetically modified glyphosate-tolerant soybeans (line 40-3-2) and local...
In this study, the physiochemical and antioxidant properties of the soybean hulls from the genetically modified glyphosate-tolerant soybeans (line 40-3-2) and local cultivar northeast soybeans were investigated. The levels of fat, total phenolic, total extractable pectin and soluble dietary fiber in northeast soybeans hulls were less than that in glyphosate-tolerant soybeans hulls, respectively. The antioxidant capacity of total phenolic, water soluble pectin, and soluble dietary fiber showed that DPPH free radical scavenging activities of glyphosate-tolerant soybeans hulls were 118.23, 57.34 and 197.22 μg AAE/g, which were 2.3, 1.2 and 9.4 times of northeast soybeans hulls, respectively ( < 0.05), and FRAP of glyphosate-tolerant soybeans hulls were 401.67, 747.51 and 328.53 μg AAE/g, which were 1.8, 8.7 and 4.8 times of northeast soybeans hulls ( < 0.05). Glyphosate-tolerant soybeans hulls extract showed the stronger antioxidant activity, which was positively correlated with total phenolic content (r = 0.890, = 0.001). It provides evidence on developing value-added utilization of hulls, soybean processing by-products, as nutraceuticals or functional food ingredients.
PubMed: 33936841
DOI: 10.1007/s10068-021-00894-z -
Molecules (Basel, Switzerland) Mar 2021The biological activity of apple pectin extracted conventionally or enzymatically using endo-xylanase and endo-cellulase, was tested in vitro. The analyses were...
The biological activity of apple pectin extracted conventionally or enzymatically using endo-xylanase and endo-cellulase, was tested in vitro. The analyses were performerd in tetraplicates and the statistical significance of the differences were assessed using ANOVA, Tukey post hoc and LSD (the least significant difference) tests. Multivariate regression analysis was applied to determine the structural components that have a crucial importance for antioxidant and antitumor properties of pectins. The pectins extracted by enzymes contained up to four times more ferulic acid and showed twice as great ability to neutralize free radicals and Fe(III) reduction. The antiradical potential positively correlated with phenols, fucose and rhamnose content. In the assays performed on HT-29 human adenocarcinoma and B16F10 melanoma cell cultures, the "green" pectins, contrary to acid isolated ones, exhibited remarkable anti-neoplastic potential while being nontoxic to nontransformed L929 cell line. The pectins in the dose of 1 mg/mL were capable of inhibiting adhesion (max 23.1%), proliferation (max 40.4%), invasion (max 76.9%) and anchorage-independent growth (max 90%) of HT-29 cells (significance level < 0.001). These pectin preparations were slightly less active towards B16F10 cells. The enzyme-isolated apple pectins may be useful as a functional food additive and an ingredient of the ointment formulas for post-surgical melanoma treatment.
Topics: Antineoplastic Agents; Antioxidants; Apoptosis; Cell Proliferation; Cellulase; Colonic Neoplasms; Endo-1,4-beta Xylanases; Humans; Malus; Melanoma; Pectins; Tumor Cells, Cultured
PubMed: 33800895
DOI: 10.3390/molecules26051434 -
Theranostics 2021Anti-PD-1-based immunotherapy has emerged as a promising therapy for several cancers. However, it only benefits a small subset of colorectal cancer (CRC) patients....
Anti-PD-1-based immunotherapy has emerged as a promising therapy for several cancers. However, it only benefits a small subset of colorectal cancer (CRC) patients. Mounting data supports the pivotal role of gut microbiota in shaping immune system. Pectin, a widely consumed soluble fiber, has been reported to ameliorate the imbalance of gut microbiota. Therefore, we aimed to explore the effect and the underlying mechanisms of pectin in improving anti-PD-1 mAb efficacy. The C57BL/6 mice were treated with a broad-spectrum antibiotic (ATB) cocktail to depleted endogenous gut microbiota and subsequently humanized with feces from healthy controls or newly diagnosed CRC patients. The antitumor efficacies of anti-PD-1 mAb combined with or without pectin were assessed using these mice. Flow cytometry and immunohistochemistry (IHC) were conducted to investigate the tumor immune microenvironment after treatment. The gut microbiota profiles and short-chain fatty acids (SCFAs) levels were determined by 16S ribosomal RNA (16S rRNA) gene sequencing and gas chromatography-mass spectrometry (GC-MS), respectively. The effect of gut microbiota on anti-PD-1 mAb efficacy after pectin supplement was further tested by fecal microbiota transplantation (FMT). The anti-PD-1 mAb efficacy was largely impaired in the mice humanized with feces from newly diagnosed CRC patients compared to those from healthy controls. However, pectin significantly enhanced the anti-PD-1 mAb efficacy in the tumor-bearing mice humanized with CRC patient gut microbiota. Flow cytometry and IHC analysis revealed increased T cell infiltration and activation in the tumor microenvironment of mice treated with anti-PD-1 mAb plus pectin. In vivo depletion of CD8 T cells diminished the anti-tumor effect of anti-PD-1 mAb combined with pectin. 16S rRNA gene sequencing showed that pectin significantly increased gut microbial diversity and beneficially regulated microbial composition. In addition, we identified unique bacterial modules that were significantly enriched in the anti-PD-1 mAb + pectin group, which composed of butyrate-producing bacteria indicative of good response to immunotherapy. Meanwhile, GC-MS showed that pectin altered the level of SCFA butyrate. Furthermore, butyrate, a main product of dietary fiber in gut microbial fermentation, was found to be sufficient to promote T cells infiltration and thus enhance the efficacy of anti-PD-1 mAb. In addition, FMT demonstrated the effects of pectin were dependent on gut microbiota. Importantly, the beneficial effects of pectin were confirmed in the mice humanized with gut microbiota from patient with resistance to anti-PD-1 mAb. Pectin facilitated the anti-PD-1 mAb efficacy in CRC via regulating the T cell infiltration in the tumor microenvironment, which was potentially mediated by the metabolite butyrate.
Topics: Aged; Animals; Antibodies, Monoclonal; Bacteria; CD8-Positive T-Lymphocytes; Cell Line, Tumor; Colorectal Neoplasms; Fatty Acids, Volatile; Feces; Female; Gastrointestinal Microbiome; Humans; Male; Mice; Mice, Inbred C57BL; Pectins; Programmed Cell Death 1 Receptor; RNA, Ribosomal, 16S; Tumor Microenvironment
PubMed: 33754054
DOI: 10.7150/thno.54476 -
BioMed Research International 2021Antiseptic wound ointments are widely used to treat dermal wounds that are microbially contaminated. Polygalacturonic acid (PG)+caprylic acid (CAP) is a novel...
Antiseptic wound ointments are widely used to treat dermal wounds that are microbially contaminated. Polygalacturonic acid (PG)+caprylic acid (CAP) is a novel combination that has been shown to eradicate biofilms. We developed a novel PG+CAP ointment and compared the biofilm eradication capability and cytotoxicity of PG+CAP with that of commercially available antiseptic wound ointments. We used a well-established biofilm model to quantitatively assess the eradication of organisms following exposure to the wound ointments for 2 hours. PG+CAP ointment completely eradicated , multidrug-resistant , and methicillin-resistant biofilms, whereas MediHoney, polyhexamethylene biguanide (PHMB), and benzalkonium chloride (BZK) ointments failed to eradicate all biofilms within 2 hours. We assessed cytotoxicity by exposing L-929 fibroblasts to extracts of each ointment; Trypan blue exclusion was used to assess cell viability, and Alamar blue conversion was used to assess metabolic function. After exposure to PG+CAP and MediHoney, fibroblast viability was 96.23% and 95.23%, respectively (Trypan blue), and was comparable to untreated cells (98.77%). PHMB and BZK showed reduced viability (83.25% and 77.83%, respectively, < 0.05). Metabolic activity results followed a similar pattern. Cytotoxicity of PG+CAP ointment towards erythrocytes was comparable to saline. PG+CAP ointment seems to be safe and can rapidly eradicate microbial biofilm; thus, PG+CAP ointment merits further in vivo testing as a potential antimicrobial wound ointment.
Topics: Animals; Anti-Infective Agents, Local; Biofilms; Candida albicans; Caprylates; Cell Line; Methicillin-Resistant Staphylococcus aureus; Mice; Ointments; Pectins; Pseudomonas aeruginosa
PubMed: 33708989
DOI: 10.1155/2021/2710484 -
BMC Plant Biology Jan 2021Physical seed dormancy is an important trait in legume domestication. Although seed dormancy is beneficial in wild ecosystems, it is generally considered to be an...
BACKGROUND
Physical seed dormancy is an important trait in legume domestication. Although seed dormancy is beneficial in wild ecosystems, it is generally considered to be an undesirable trait in crops due to reduction in yield and / or quality. The physiological mechanism and underlying genetic factor(s) of seed dormancy is largely unknown in several legume species. Here we employed an integrative approach to understand the mechanisms controlling physical seed dormancy in common bean (Phaseolus vulgaris L.).
RESULTS
Using an innovative CT scan imaging system, we were able to track water movements inside the seed coat. We found that water uptake initiates from the bean seed lens. Using a scanning electron microscopy (SEM) we further identified several micro-cracks on the lens surface of non-dormant bean genotypes. Bulked segregant analysis (BSA) was conducted on a bi-parental RIL (recombinant inbred line) population, segregating for seed dormancy. This analysis revealed that the seed water uptake is associated with a single major QTL on Pv03. The QTL region was fine-mapped to a 118 Kb interval possessing 11 genes. Coding sequence analysis of candidate genes revealed a 5-bp insertion in an ortholog of pectin acetylesterase 8 that causes a frame shift, loss-of-function mutation in non-dormant genotype. Gene expression analysis of the candidate genes in the seed coat of contrasting genotypes indicated 21-fold lower expression of pectin acetylesterase 8 in non-dormant genotype. An analysis of mutational polymorphism was conducted among wild and domesticated beans. Although all the wild beans possessed the functional allele of pectin acetylesterase 8, the majority (77%) of domesticated beans had the non-functional allele suggesting that this variant was under strong selection pressure through domestication.
CONCLUSIONS
In this study, we identified the physiological mechanism of physical seed dormancy and have identified a candidate allele causing variation in this trait. Our findings suggest that a 5-bp insertion in an ortholog of pectin acetylesterase 8 is likely a major causative mutation underlying the loss of seed dormancy during domestication. Although the results of current study provide strong evidences for the role of pectin acetylesterase 8 in seed dormancy, further confirmations seem necessary by employing transgenic approaches.
Topics: Chromosome Mapping; Chromosomes, Plant; Crops, Agricultural; Domestication; Ecosystem; Esterases; Genotype; Microscopy, Electron, Scanning; Mutagenesis, Insertional; Phaseolus; Phenotype; Plant Dormancy; Plant Proteins; Quantitative Trait Loci; Seeds; Water
PubMed: 33482732
DOI: 10.1186/s12870-021-02837-6 -
Scientific Reports Dec 2020Contemplating the exemplary benefits of pectin on human health, we precisely characterized and evaluated the antibacterial and anticancer activities from purified...
Contemplating the exemplary benefits of pectin on human health, we precisely characterized and evaluated the antibacterial and anticancer activities from purified Mulberry Fruit Pectins (MFP). Here, we tested BR-2 and S-13 varieties of mulberry fruit pectins against six bacterial strains and two human cancer cell lines (HT-29 and Hep G-2), using MIC and an in vitro cell-based assay respectively. The BR-2 mulberry fruit pectin performs superior to S-13 by inhibiting strong bacterial growth (MIC = 500-1000 μg/mL) against tested bacterial strains and cytotoxic activities at the lowest concentration (10 µg/ml) against the Hep G-2 cell line. However, both tested drugs failed to exhibit cytotoxicity on the human colon cancer cell line (HT-29). Based on molecular interaction through docking, pectin binds effectively with the receptors (1e3g, 3t0c, 5czz, 6j7l, 6v40, 5ibs, 5zsy, and 6ggb) and proven to be a promising antimicrobial and anti-cancer agents. The pursuit of unexploited drugs from mulberry fruit pectin will potentially combat against bacterial and cancer diseases. Finally, future perspectives of MFP for the treatment of many chronic diseases will help immensely due to their therapeutic properties.
Topics: Anti-Bacterial Agents; Cytotoxins; Drug Screening Assays, Antitumor; Fruit; HT29 Cells; Hep G2 Cells; Humans; Molecular Docking Simulation; Morus; Pectins
PubMed: 33311512
DOI: 10.1038/s41598-020-78086-8 -
Carbohydrate Polymers Jan 2021Pectins have anti-inflammatory effects via Toll-like receptor (TLR) inhibition in a degree of methyl-esterification-(DM)-dependent manner. However, pectins also vary in...
Pectins have anti-inflammatory effects via Toll-like receptor (TLR) inhibition in a degree of methyl-esterification-(DM)-dependent manner. However, pectins also vary in distribution of methyl-esters over the galacturonic-acid (GalA) backbone (Degree of Blockiness - DB) and impact of this on anti-inflammatory capacity is unknown. Pectins mainly inhibit TLR2-1 but magnitude depends on both DM and DB. Low DM pectins (DM18/19) with both low (DB86) and high DB (DB94) strongly inhibit TLR2-1. However, pectins with intermediate DM (DM43/DM49) and high DB (DB60), but not with low DB (DB33), inhibit TLR2-1 as strongly as low DM. High DM pectins (DM84/88) with DB71 and DB91 do not inhibit TLR2-1 strongly. Pectin-binding to TLR2 was confirmed by capture-ELISA. In human macrophages, low DM and intermediate DM pectins with high DB inhibited TLR2-1 induced IL-6 secretion. Both high number and blockwise distribution of non-esterified GalA in pectins are responsible for the anti-inflammatory effects via inhibition of TLR2-1.
Topics: Anti-Inflammatory Agents; Cell Line; Chromatography, High Pressure Liquid; Esterification; Esters; Hexuronic Acids; Humans; Inflammation; Macrophages; Pectins; Toll-Like Receptor 2
PubMed: 33152851
DOI: 10.1016/j.carbpol.2020.117093 -
Ecotoxicology and Environmental Safety Dec 2020Cell wall (CW) plays an important role in Cd accumulation in roots of metal-tolerant plants, including rice. The role of CW polysaccharides, especially pectin, in...
Cell wall (CW) plays an important role in Cd accumulation in roots of metal-tolerant plants, including rice. The role of CW polysaccharides, especially pectin, in binding Cd in roots of a high Cd accumulating (HA) rice line of Lu527-8 and a non-high Cd accumulating (NHA) rice line of Lu527-4 was investigated in this study. About 59%-63% of Cd in roots of the two rice lines was bound to CWs, indicating that CW was the main site for Cd accumulation in roots of the two rice lines. Cd adsorbed on the root CWs of the HA was 1.1-1.2 times more than that of the NHA, demonstrating the root CWs of the HA showed greater Cd binding ability. Cd exposure induced more Cd accumulation in pectin and hemicellulose in the HA. In particular, up to 65% of Cd accumulation in root CWs of the HA was observed in pectin. The removal of pectin lead to a 50% decrease for the amounts of Cd adsorption on root CWs of the HA, indicating that pectin was the major binding site for Cd in root CWs of the HA. The HA showed greater pectin methylesterase activities, resulting in lower degree of pectin methylesterification along with more low-methylesterified pectins in root CWs than the NHA. The more accumulation of low-methylesterified pectins in CWs induced by Cd contributed greatly to the high Cd accumulation in roots of the HA rice line of Lu527-8.
Topics: Adsorption; Bioaccumulation; Cadmium; Cell Wall; Oryza; Pectins; Plant Roots; Polysaccharides; Soil Pollutants
PubMed: 32890925
DOI: 10.1016/j.ecoenv.2020.111210