Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 20 de 977
1.
Int J Biol Macromol ; 269(Pt 2): 131918, 2024 Jun.
Article En | MEDLINE | ID: mdl-38697418

Polygalacturonases (PGs) can modulate chemistry and mechanical properties of the plant cell wall through the degradation of pectins, one of its major constituents. PGs are largely used in food, beverage, textile, and paper industries to increase processes' performances. To improve the use of PGs, knowledge of their biochemical, structural and functional features is of prime importance. Our study aims at characterizing SmoPG1, a polygalacturonase from Selaginella moellendorffii, that belongs to the lycophytes. Transcription data showed that SmoPG1 was mainly expressed in S. moellendorffii shoots while phylogenetic analyses suggested that SmoPG1 is an exo-PG, which was confirmed by the biochemical characterization following its expression in heterologous system. Indeed, LC-MS/MS oligoprofiling using various pectic substrates identified galacturonic acid (GalA) as the main hydrolysis product. We found that SmoPG1 was most active on polygalacturonic acid (PGA) at pH 5, and that its activity could be modulated by different cations (Ca2+, Cu2+, Fe2+, Mg2+, Mn2+, Na2+, Zn2+). In addition, SmoPG1 was inhibited by green tea catechins, including (-)-epigallocatechin-3-gallate (EGCG). Docking analyses and MD simulations showed in detail amino acids responsible for the SmoPG1-EGCG interaction. Considering its expression yield and activity, SmoPG1 appears as a prime candidate for the industrial production of GalA.


Pectins , Polygalacturonase , Selaginellaceae , Polygalacturonase/metabolism , Polygalacturonase/chemistry , Polygalacturonase/genetics , Selaginellaceae/chemistry , Selaginellaceae/genetics , Selaginellaceae/enzymology , Pectins/metabolism , Pectins/chemistry , Phylogeny , Substrate Specificity , Molecular Docking Simulation , Amino Acid Sequence , Hydrogen-Ion Concentration , Hydrolysis , Hexuronic Acids
2.
Int J Biol Macromol ; 269(Pt 2): 132054, 2024 Jun.
Article En | MEDLINE | ID: mdl-38704063

In this study, we analyzed the pectin structure within the pulp of cassava. Cassava pectin, derived from cassava pulp treatment at 120 °C for 90 min, was separated into four fractions (CP-P, CP-SD1, CP-SD2F, and CP-SD2R) based on variations in water solubility, electrical properties, and molecular weights. Sugar composition analysis demonstrated an abundance of homogalacturonan (HG) in CP-P and CP-SD2F, rhamnogalacturonan I (RG-I) in CP-SD2R, and neutral sugars in CP-SD1. Because RG-I possesses a complex structure, we analyzed CP-SD2R using various pectinolytic enzymes. Galactose was the major sugar in CP-SD2R accounting for 49 %, of which 65 % originated from arabinogalactan I, 9 % from galactose and galactooligosaccharides, 5 % from arabinogalactan II, and 11 % from galactoarabinan. Seventy-four percent of arabinose in CP-SD2R was present as galactoarabinan. The methylation (DM) and acetylation (DAc) degrees of cassava pectin were 11 and 15 %, respectively. The HG and RG-I regions exhibited DAc values of 5 and 44 %, respectively, signifying the high DAc of RG-I compared to HG. Information derived from the structural analysis of cassava pectin will enable efficient degradation of pectin and cellulose, leading to the use of cassava pulp as a raw material for biorefineries.


Manihot , Pectins , Manihot/chemistry , Pectins/chemistry , Chemical Fractionation , Molecular Weight , Polygalacturonase/chemistry , Polygalacturonase/metabolism , Methylation , Solubility
3.
Int J Biol Macromol ; 267(Pt 2): 131565, 2024 May.
Article En | MEDLINE | ID: mdl-38614184

Endopolygalacturonases are crucial pectinases known for their efficient and sustainable pectin depolymerization activities. The present study identified a novel gene encoding endopolygalacturonase from an acidic mine tailing metagenome. The putative gene showed a maximum identity of 67.55 % with an uncharacterized peptide sequence from Flavobacterium fluvii. The gene was cloned and expressed in a heterologous host, E. coli. Biochemical characterization of the novel endopolygalacturonase enzyme variant (EPHM) showed maximum activity at 60 °C and at 5.0 pH, while retaining 50 % activity under the temperature and pH range of 20 °C to 70 °C for 6 h, and 3.0 to 10.0 for 3 h, respectively. The enzyme exhibited tolerance to different metal ions. EPHM was characterized for the depolymerization of methylated pectin into pectic oligosaccharides. Further, its utility was established for fruit juice clarification, as endorsed by high transmittance, significant viscosity reduction, and release of reducing sugars in the treated fruit juice samples.


Fruit and Vegetable Juices , Pectins , Polygalacturonase , Pectins/metabolism , Pectins/chemistry , Polygalacturonase/metabolism , Polygalacturonase/chemistry , Polygalacturonase/genetics , Fruit and Vegetable Juices/analysis , Hydrogen-Ion Concentration , Temperature , Cloning, Molecular , Polymerization , Oligosaccharides/chemistry
4.
Food Funct ; 15(9): 4887-4893, 2024 May 07.
Article En | MEDLINE | ID: mdl-38597504

Inhibition of galectin-3-mediated interactions by modified citrus pectin (MCP) could affect several rate-limiting steps in cancer metastasis, but the ability of MCP to antagonize galectin-8 function remains unknown. We hypothesized that MCP could bind to galectin-8 in addition to galectin-3. In this study, a combination of gradual ethanol precipitation and DEAE-Sepharose Fast Flow chromatography was used to isolate several fractions from MCP. The ability of these fractions to antagonize galectin-8 function was studied as well as the primary structure and initial structure-function relationship of the major active component MCP-30-3. The results showed that MCP-30-3 (168 kDa) was composed of Gal (13.8%), GalA (63.1%), GlcA (13.0%), and Glc (10.1%). MCP-30-3 could specifically bind to galectin-8, with an MIC value of 0.04 mg mL-1. After MCP-30-3 was hydrolyzed by ß-galactosidase or pectinase, its binding activity was significantly reduced. These results provide new insights into the interaction between MCP structure and galectin function, as well as the potential utility in the development of functional foods.


Galectins , Pectins , Pectins/chemistry , Pectins/pharmacology , Galectins/metabolism , Galectins/chemistry , Humans , Citrus/chemistry , Galectin 3/metabolism , Blood Proteins/chemistry , Blood Proteins/metabolism , Protein Binding , Polygalacturonase/chemistry , Polygalacturonase/metabolism
5.
Int J Biol Macromol ; 267(Pt 1): 131469, 2024 May.
Article En | MEDLINE | ID: mdl-38604432

Pectic polysaccharide is a bioactive ingredient in Chrysanthemum morifolium Ramat. 'Hangbaiju' (CMH), but the high proportion of HG domain limited its use as a prebiotic. In this study, hot water, cellulase-assisted, medium-temperature alkali, and deep eutectic solvent extraction strategies were firstly used to extract pectin from CMH (CMHP). CMHP obtained by cellulase-assisted extraction had high purity and strong ability to promote the proliferation of Bacteroides and mixed probiotics. However, 4 extraction strategies led to general high proportion of HG domain in CMHPs. To further enhance the dissolution and prebiotic potential of CMHP, pectinase was used alone and combined with cellulase. The key factor for the optimal extraction was enzymolysis by cellulase and pectinase in a mass ratio of 3:1 at 1 % (w/w) dosage. The optimal CMHP had high yield (15.15 %), high content of total sugar, and Bacteroides proliferative activity superior to inulin, which was probably due to the cooperation of complex enzyme on the destruction of cell wall and pectin structural modification for raised RG-I domain (80.30 %) with relatively high degree of branching and moderate HG domain. This study provided a green strategy for extraction of RG-I enriched prebiotic pectin from plants.


Bacteroides , Chrysanthemum , Pectins , Pectins/chemistry , Chrysanthemum/chemistry , Cell Proliferation/drug effects , Cellulase/chemistry , Cellulase/metabolism , Solubility , Polygalacturonase/chemistry , Polygalacturonase/metabolism
6.
Int J Biol Macromol ; 266(Pt 2): 131309, 2024 May.
Article En | MEDLINE | ID: mdl-38580019

Enzymatic degradation of plant biomass requires the coordinated action of various enzymes. In this study, the production of reducing sugars from pectic substrates and sugar beet pulp (SBP) was investigated and compared using commercial enzyme preparations, including M2, pectinase (E1), Viscozyme L (V-L) and L-40. V-L, a cellulolytic enzyme mix produced by Aspergillus sp. was further evaluated as the most robust enzyme cocktail with the strongest SBP degradation ability in terms of the release of monosaccharides, methanol, and acetate from SBP. Mass-spectrometry-based proteomics analysis of V-L revealed 156 individual proteins. Of these, 101 proteins were annotated as containing a carbohydrate-active enzyme module. Notably, of the 50 most abundant proteins, ca. 44 % were predicted to be involved in pectin degradation. To reveal the role of individual putative key enzymes in pectic substrate decomposition, two abundant galacturonases (PglA and PglB), were heterologously expressed in Pichia pastoris and further characterized. PglA and PglB demonstrated maximum activity at 57 °C and 68 °C, respectively, and exhibited endo-type cleavage patterns towards polygalacturonic acid. Further studies along this line may lead to a better understanding of efficient SBP degradation and may help to design improved artificial enzyme mixtures with lower complexity for future application in biotechnology.


Pectins , Proteomics , Pectins/metabolism , Proteomics/methods , Substrate Specificity , Polygalacturonase/metabolism , Polygalacturonase/chemistry , Beta vulgaris/chemistry , Beta vulgaris/metabolism , Aspergillus/enzymology
7.
Molecules ; 29(5)2024 Feb 28.
Article En | MEDLINE | ID: mdl-38474547

Enzymatic hydrolysis using pectinase is critical for producing high-yield and quality sea buckthorn juice. This study determined the optimal temperature, time, and enzyme dosage combinations to guide manufacturers. A temperature of 60 °C, hydrolysis time of 3 h, and 0.3% enzyme dosage gave 64.1% juice yield-25% higher than without enzymes. Furthermore, monitoring physicochemical properties reveals enzyme impacts on composition. Higher dosages increase soluble solids up to 15% and soluble fiber content by 35% through cell wall breakdown. However, excessive amounts over 0.3% decrease yields. Pectin concentration also declines dose-dependently, falling by 91% at 0.4%, improving juice stability but needing modulation to retain viscosity. Electrochemical fingerprinting successfully differentiates process conditions, offering a rapid quality control tool. Its potential for commercial inline use during enzymatic treatment requires exploration. Overall, connecting optimized parameters to measured effects provides actionable insights for manufacturers to boost yields, determine enzyme impacts on nutrition/functionality, and introduce novel process analytical technology. Further investigations of health properties using these conditions could expand sea buckthorn juice functionality.


Hippophae , Polygalacturonase , Polygalacturonase/metabolism , Hippophae/metabolism , Temperature , Fruit/chemistry , Hydrolysis
8.
Int J Biol Macromol ; 264(Pt 1): 130476, 2024 Apr.
Article En | MEDLINE | ID: mdl-38428761

A whole-cell biocatalyst was developed by genetically engineering pectinase PG5 onto the cell surface of Pichia pastoris using Gcw12 as the anchoring protein. Whole-cell PG5 eliminated the need for enzyme extraction and purification, while also exhibiting enhanced thermal stability, pH stability, and resistance to proteases in vitro compared to free PG5. Magnetic resonance mass spectrometry analysis revealed that whole-cell PG5 efficiently degraded citrus pectin, resulting in the production of a mixture of pectin oligosaccharides. The primary components of the mixture were trigalacturonic acid, followed by digalacturonic acid and tetragalacturonic acid. Supplementation of citrus pectin with whole-cell PG5 resulted in a more pronounced protective effect compared to free PG5 in alleviating colitis symptoms and promoting the integrity of the colonic epithelial barrier in a mouse model of dextran sulfate sodium-induced colitis. Hence, this study demonstrates the potential of utilizing whole-cell pectinase as an effective biocatalyst to promote intestinal homeostasis in vivo.


Colitis , Polygalacturonase , Saccharomycetales , Animals , Mice , Polygalacturonase/genetics , Polygalacturonase/metabolism , Intestinal Barrier Function , Colitis/chemically induced , Colitis/drug therapy , Colitis/metabolism , Pectins/pharmacology , Pectins/metabolism , Dietary Supplements
9.
Enzyme Microb Technol ; 177: 110424, 2024 Jun.
Article En | MEDLINE | ID: mdl-38479075

In this work, the polygalacturonase (TL-PG1) from the thermophilic fungus Thermomyces lanuginosus was heterologously produced for the first time in the yeast Komagataella phaffii. The TL-PG1 was successfully expressed under the control of the AOX1 promoter and sequentially purified by His-tag affinity. The purified recombinant pectinase exhibited an activity of 462.6 U/mL toward polygalacturonic acid under optimal conditions (pH 6 and 55 ˚C) with a 2.83 mg/mL and 0.063 µmol/minute for Km and Vmax, respectively. When used as supplementation for biomass hydrolysis, TL-PG1 demonstrated synergy with the enzymatic cocktail Ctec3 to depolymerize orange citrus pulp, releasing 1.43 mg/mL of reducing sugar. In addition, TL-PG1 exhibited efficiency in fabric bioscouring, showing potential usage in the textile industry. Applying a protein dosage of 7 mg/mL, the time for the fabric to absorb water was 19.77 seconds (ten times faster than the control). Adding the surfactant Triton to the treatment allowed the reduction of the enzyme dosage by 50% and the water absorption time to 6.38 seconds. Altogether, this work describes a new versatile polygalacturonase from T. lanuginosus with the potential to be employed in the hydrolysis of lignocellulosic biomass and bioscouring.


Fungal Proteins , Polygalacturonase , Saccharomycetales , Biomass , Eurotiales/enzymology , Eurotiales/genetics , Fungal Proteins/genetics , Fungal Proteins/metabolism , Hydrolysis , Kinetics , Polygalacturonase/metabolism , Polygalacturonase/genetics , Recombinant Proteins/metabolism , Recombinant Proteins/genetics , Saccharomycetales/genetics , Saccharomycetales/enzymology , Saccharomycetales/metabolism , Textile Industry , Textiles
10.
Int J Biol Macromol ; 266(Pt 2): 130968, 2024 May.
Article En | MEDLINE | ID: mdl-38521324

The investigation aims to determine the effect of enzymatic and alkali treatments on Sambucus ebulus L. stem fiber. For this purpose, Sambucus ebulus L. stem fibers were treated with alkali, cellulase, and pectinase enzymes. An image processing technique was developed and implemented to calculate the average thicknesses of Sambucus ebulus L. fibers. The thickness of alkali, cellulase and pectinase enzyme treated fibers was determined as 478.62 µm, 808.28 µm and 478.20 µm, respectively. Scanning electron microscopy analysis illustrated that enzymatic and alkali treatments lead to the breakage of fiber structure. Furthermore, enzymatic and alkali treatments induce variations in elemental ingredients. All treatments increased the crystallinity index of Sambucus ebulus L. fiber from 72 % (raw fiber) to 83 % (alkali treated), 75.2 % (cellulase enzyme treated) and 86.3 % (pectinase enzyme treated) due to the hydrolysis of hemicellulose. Fourier transform infrared analysis indicated that there are no significant differences in functional groups. Thermogravimetric analysis shows that enzymatic and alkali treatments improve final degradation temperature of the fiber. Mechanical behaviors of cellulase enzyme-treated fiber decrease compared to raw fiber, while pectinase enzyme and alkali treatment cause to improve mechanical properties. Tensile strength of samples was determined as 76.4 MPa (cellulase enzyme treated fiber), 210 MPa (pectinase enzyme treated fiber) and 240 MPa (alkali treated fiber). Young's modules of cellulase enzyme, pectinase enzyme and alkali treated fibers were predicted as 5.5 GPa, 13.1 GPa and 16.6 GPa. Elongation at break of samples was calculated as 5.5 % (cellulase enzyme treated fiber), 6.5 % (pectinase enzyme treated fiber) and 6 % (alkali treated fiber). The results suggest that enzymatic and alkali treatments can modify the functional and structural attributes of Sambucus ebulus L. fiber.


Alkalies , Cellulase , Polygalacturonase , Sambucus , Cellulase/metabolism , Cellulase/chemistry , Polygalacturonase/chemistry , Polygalacturonase/metabolism , Sambucus/chemistry , Alkalies/chemistry , Hydrolysis , Chemical Phenomena , Polysaccharides/chemistry
11.
Science ; 383(6684): 732-739, 2024 Feb 16.
Article En | MEDLINE | ID: mdl-38359129

Polygalacturonase-inhibiting proteins (PGIPs) interact with pathogen-derived polygalacturonases to inhibit their virulence-associated plant cell wall-degrading activity but stimulate immunity-inducing oligogalacturonide production. Here we show that interaction between Phaseolus vulgaris PGIP2 (PvPGIP2) and Fusarium phyllophilum polygalacturonase (FpPG) enhances substrate binding, resulting in inhibition of the enzyme activity of FpPG. This interaction promotes FpPG-catalyzed production of long-chain immunoactive oligogalacturonides, while diminishing immunosuppressive short oligogalacturonides. PvPGIP2 binding creates a substrate binding site on PvPGIP2-FpPG, forming a new polygalacturonase with boosted substrate binding activity and altered substrate preference. Structure-based engineering converts a putative PGIP that initially lacks FpPG-binding activity into an effective FpPG-interacting protein. These findings unveil a mechanism for plants to transform pathogen virulence activity into a defense trigger and provide proof of principle for engineering PGIPs with broader specificity.


Fusarium , Phaseolus , Plant Immunity , Plant Proteins , Polygalacturonase , Virulence Factors , Immunity, Innate , Plant Proteins/metabolism , Polygalacturonase/metabolism , Virulence Factors/metabolism , Fusarium/immunology , Fusarium/pathogenicity , Phaseolus/immunology , Phaseolus/microbiology
12.
Sci Rep ; 14(1): 5037, 2024 02 29.
Article En | MEDLINE | ID: mdl-38424450

The filamentous Thermoascus aurantiacus fungus characterized by its thermophilic nature, is recognized as an exceptional producer of various enzymes with biotechnological applications. This study aimed to explore biotechnological applications using polygalacturonase (PG) derived from the Thermoascus aurantiacus PI3S3 strain. PG production was achieved through submerged fermentation and subsequent purification via ion-exchange chromatography and gel filtration methods. The crude extract exhibited a diverse spectrum of enzymatic activities including amylase, cellulase, invertase, pectinase, and xylanase. Notably, it demonstrated the ability to hydrolyze sugarcane bagasse biomass, corn residue, and animal feed. The purified PG had a molecular mass of 36 kDa, with optimal activity observed at pH 4.5 and 70 °C. The activation energy (Ea) was calculated as 0.513 kJ mol-1, highlighting activation in the presence of Ca2+. Additionally, it displayed apparent Km, Vmax, and Kcat values of at 0.19 mg mL-1, 273.10 U mL-1, and 168.52 s-1, respectively, for hydrolyzing polygalacturonic acid. This multifunctional PG exhibited activities such as denim biopolishing, apple juice clarification, and demonstrated both endo- and exo-polygalacturonase activities. Furthermore, it displayed versatility by hydrolyzing polygalacturonic acid, carboxymethylcellulose, and xylan. The T. aurantiacus PI3S3 multifunctional polygalacturonase showed heightened activity under acidic pH, elevated temperatures, and in the presence of calcium. Its multifunctional nature distinguished it from other PGs, significantly expanding its potential for diverse biotechnological applications.


Saccharum , Thermoascus , Polygalacturonase/metabolism , Thermoascus/metabolism , Cellulose , Multifunctional Enzymes , Saccharum/metabolism , Hydrogen-Ion Concentration , Enzyme Stability , Temperature
13.
Food Chem ; 441: 138298, 2024 May 30.
Article En | MEDLINE | ID: mdl-38199103

Food quality is greatly impacted by traditional heat methods for polygalacturonase (PG) inactivation; therefore, it's imperative to develop a novel infrared (IR) inactivation approach and identify its mechanism. Utilizing molecular dynamics (MD) simulation, this study verified the PG's activity, structure, active sites, and substrate channel under the single thermal and non-thermal effects of IR. PG activity was significantly reduced by IR, and structure was unfolded by increasing random coils (65.62 %) and decreasing ß-sheets (29.11 %). MD data indicated that the relative locations of PG's active sites were altered by both IR effects, and the enzyme-substrate channel was shortened (10.53 % at 18 µm and 15.79 % at 80 °C). The thermal effect of IR on the inactivation of PG was significantly more pronounced than its non-thermal effect. This study unveiled the mechanism by which the infrared disrupted PG's activity, active sites, and substrate channels; thus, it expanded the infrared technique's efficacy in enzyme control.


Molecular Dynamics Simulation , Polygalacturonase , Polygalacturonase/metabolism
14.
Bioresour Technol ; 394: 130283, 2024 Feb.
Article En | MEDLINE | ID: mdl-38163489

The current research discusses a multidimensional bioprocess development, that includes bioprospecting, strain improvement, media optimisation, and applications of the extracted enzyme. A potent alkalophilic polygalacturonase (PG) producing bacterial strain was isolated and identified as a novel Glutamicibacter sp. Furthermore, strain improvement by UV and chemical mutagenesis not only improved the enzyme (PGmut) production but also enhanced its temperature optima from 37 °C to 50 °C. The use of solid substrate fermentation, followed bystatistical optimisation through PB and RSM, substantially increasedPGmut production. A 10-fold increase in enzyme production (632 U/gm) was observed when sugarcane bagasse with a pH of 10.5, 66.8 % moisture, and an inoculum size of 10.15 % was used. The model's accuracy was supported by p-value (p < 0.0001), and an R2 of 0.9940. A pilot-scale experiment, demonstrated ≈ 62,229 U/100 gm PG activity. Additionally, the enzyme's efficacy in demucilization of coffee beans, and bioscouring of jute fibre indicated that it is a valuable biocatalyst.


Polygalacturonase , Saccharum , Polygalacturonase/metabolism , Cellulose , Bioprospecting , Saccharum/metabolism , Fermentation
15.
Int J Biol Macromol ; 254(Pt 1): 127804, 2024 Jan.
Article En | MEDLINE | ID: mdl-37913880

Pectin, a complex natural macromolecule present in primary cell walls, exhibits high structural diversity. Pectin is composed of a main chain, which contains a high amount of partly methyl-esterified galacturonic acid (GalA), and numerous types of side chains that contain almost 17 different monosaccharides and over 20 different linkages. Due to this peculiar structure, pectin exhibits special physicochemical properties and a variety of bioactivities. For example, pectin exhibits strong bioactivity only in a low molecular weight range. Many different degrading enzymes, including hydrolases, lyases and esterases, are needed to depolymerize pectin due to its structural complexity. Pectin degradation involves polygalacturonases/rhamnogalacturonases and pectate/pectin lyases, which attack the linkages in the backbone via hydrolytic and ß-elimination modes, respectively. Pectin methyl/acetyl esterases involved in the de-esterification of pectin also play crucial roles. Many α-L-rhamnohydrolases, unsaturated rhamnogalacturonyl hydrolases, arabinanases and galactanases also contribute to heterogeneous pectin degradation. Although numerous microbial pectin-degrading enzymes have been described, the mechanisms involved in the coordinated degradation of pectin through these enzymes remain unclear. In recent years, the degradation of pectin by Bacteroides has received increasing attention, as Bacteroides species contain a unique genetic structure, polysaccharide utilization loci (PULs). The specific PULs of pectin degradation in Bacteroides species are a new field to study pectin metabolism in gut microbiota. This paper reviews the scientific information available on pectin structural characteristics, pectin-degrading enzymes, and PULs for the specific degradation of pectin.


Pectins , Polysaccharides , Pectins/chemistry , Polysaccharides/metabolism , Esterases/metabolism , Bacteroides/metabolism , Polygalacturonase/metabolism
16.
Int J Mol Sci ; 24(23)2023 Nov 30.
Article En | MEDLINE | ID: mdl-38069295

Polygalacturonase (PG) is one of the largest families of hydrolytic enzymes in plants. It is involved in the breakdown of pectin in the plant cell wall and even contributes to peel cracks. Here, we characterize PGs and outline their expression profiles using the available reference genome and transcriptome of Akebia trifoliata. The average length and exon number of the 47 identified AktPGs, unevenly assigned on 14 chromosomes and two unassembled contigs, were 5399 bp and 7, respectively. The phylogenetic tree of 191 PGs, including 47, 57, 51, and 36 from A. trifoliata, Durio zibethinus, Actinidia chinensis, and Vitis vinifera, respectively, showed that AktPGs were distributed in all groups except group G and that 10 AktPGs in group E were older, while the remaining 37 AktPGs were younger. Evolutionarily, all AktPGs generally experienced whole-genome duplication (WGD)/segmental repeats and purifying selection. Additionally, the origin of conserved domain III was possibly associated with a histidine residue (H) substitute in motif 8. The results of both the phylogenetic tree and expression profiling indicated that five AktPGs, especially AktPG25, could be associated with the cracking process. Detailed information and data on the PG family are beneficial for further study of the postharvest biology of A. trifoliata.


Genes, Plant , Polygalacturonase , Phylogeny , Polygalacturonase/metabolism , Transcriptome , Plants/metabolism
17.
PeerJ ; 11: e16399, 2023.
Article En | MEDLINE | ID: mdl-38050608

Wheat is the second most important staple crop grown and consumed worldwide. Temperature fluctuations especially the cold stress during the winter season reduces wheat growth and grain yield. Psychrotolerant plant growth-promoting rhizobacteria (PGPR) may improve plant stress-tolerance in addition to serve as biofertilizer. The present study aimed to isolate and identify PGPR, with the potential to tolerate cold stress for subsequent use in supporting wheat growth under cold stress. Ten psychrotolerant bacteria were isolated from the wheat rhizosphere at 4 °C and tested for their ability to grow at wide range of temperature ranging from -8 °C to 36 °C and multiple plant beneficial traits. All bacteria were able to grow at 4 °C to 32 °C temperature range and solubilized phosphorus except WR23 at 4 °C, whereas all the bacteria solubilized phosphorus at 28 °C. Seven bacteria produced indole-3-acetic acid at 4 °C, whereas all produced indole-3-acetic acid at 28 °C. Seven bacteria showed the ability to fix nitrogen at 4 °C, while all the bacteria fixed nitrogen at 28 °C. Only one bacterium showed the potential to produce cellulase at 4 °C, whereas four bacteria showed the potential to produce cellulase at 28 °C. Seven bacteria produced pectinase at 4 °C, while one bacterium produced pectinase at 28 °C. Only one bacterium solubilized the zinc at 4 °C, whereas six bacteria solubilized the zinc at 28 °C using ZnO as the primary zinc source. Five bacteria solubilized the zinc at 4 °C, while seven bacteria solubilized the zinc at 28 °C using ZnCO3 as the primary zinc source. All the bacteria produced biofilm at 4 °C and 28 °C. In general, we noticed behavior of higher production of plant growth-promoting substances at 28 °C, except pectinase assay. Overall, in vitro testing confirms that microbes perform their inherent properties efficiently at optimum temperatures rather than the low temperatures due to high metabolic rate. Five potential rhizobacteria were selected based on the in vitro testing and evaluated for plant growth-promoting potential on wheat under controlled conditions. WR22 and WR24 significantly improved wheat growth, specifically increasing plant dry weight by 42% and 58%, respectively. 16S rRNA sequence analysis of WR22 showed 99.78% similarity with Cupriavidus campinensis and WR24 showed 99.9% similarity with Enterobacter ludwigii. This is the first report highlighting the association of C. campinensis and E. ludwigii with wheat rhizosphere. These bacteria can serve as potential candidates for biofertilizer to mitigate the chilling effect and improve wheat production after field-testing.


Alphaproteobacteria , Cellulases , Triticum/genetics , RNA, Ribosomal, 16S/genetics , Polygalacturonase/metabolism , Bacteria/genetics , Phosphorus/metabolism , Alphaproteobacteria/genetics , Nitrogen/metabolism , Zinc/metabolism , Cellulases/metabolism
18.
J Food Sci ; 88(9): 3725-3736, 2023 Sep.
Article En | MEDLINE | ID: mdl-37548624

Low-temperature storage is a widely used method for peach fruit storage. However, the impact of PpCBFs on pectin degradation during low-temperature storage is unclear. As such, in this study, we stored the melting-flesh peach cultivar "Fuli" at low temperature (LT, 6°C) and room temperature (RT, 25°C) to determine the effect of different temperatures on its physiological and biochemical changes. Low-temperature storage can inhibit the softening of "Fuli" peaches by maintaining the stability of the cell wall. It was found that the contents of water-soluble pectin and ionic-soluble pectin in peach fruit stored at RT were higher than those stored at LT. The enzyme activities of polygalacturonase (PG), pectate lyase (PL), and pectin methylesterase (PME) were all inhibited by LT. The expressions of PpPME3, PpPL2, and PpPG were closely related to fruit firmness, but PpCBF2 and PpCBF3 showed higher expression levels at LT than RT. The promoters of PpPL2 and PpPG contain the DER motif, which suggested that PpCBF2 and PpCBF3 might negatively regulate their expression by directly binding to their promoters. These results indicated that LT may maintain firmness by activating PpCBFs to repress pectin-degradation-related enzyme genes during storage.


Prunus persica , Prunus persica/metabolism , Temperature , Fruit/metabolism , Pectins/metabolism , Polygalacturonase/genetics , Polygalacturonase/metabolism , Cell Wall/metabolism
19.
Lett Appl Microbiol ; 76(8)2023 Aug 02.
Article En | MEDLINE | ID: mdl-37496205

The main goal of this study was to examine the efficiency of a newly isolated fungus from quince, Aspergillus tubingensis FAT43, to produce the pectinolytic complex using agricultural and industrial waste as the substrate for solid state fermentation. Sugar beet pulp was the most effective substrate inducer of pectinolytic complex synthesis out of all the waste residues examined. For endo-pectinolytic and total pectinolytic activity, respectively, statistical optimization using Placked-Burman Design and Optimal (Custom) Design increased production by 2.22 and 2.15-fold, respectively. Liquification, clarification, and an increase in the amount of reducing sugar in fruit juices (apple, banana, apricot, orange, and quince) processed with pectinolytic complex were identified. Enzymatic pre-treatment considerably increases yield (14%-22%) and clarification (90%). After enzymatic treatment, the best liquefaction was observed in orange juice, whereas the best clarification was obtained in apricot juice. Additionally, the pectinolytic treatment of apricot juice resulted in the highest increase in reducing sugar concentration (11%) compared to all other enzymatically treated juices. Optimizing the production of a highly active pectinolytic complex and its efficient utilization in the processing of fruit juices, including the generation of an increasing amount of waste, are the significant outcomes of this research.


Fruit and Vegetable Juices , Polygalacturonase , Fermentation , Polygalacturonase/chemistry , Polygalacturonase/metabolism , Sugars
20.
J Anim Sci ; 1012023 Jan 03.
Article En | MEDLINE | ID: mdl-37422800

Enzymatic modification of canola meal (CM) is a potential method to enhance its nutritional value as it can depolymerize nonstarch polysaccharides (NSP) and mitigate its potential antinutritive properties. Based on the previous studies, pectinase A (PA), pectinase B (PB), xylanase B (XB), and invertase (Inv) were used for the enzymatic modifications. The highest NSP depolymerization ratio was obtained when 4 g/kg of each PA, PB, and XB, and 0.2 g/kg of Inv were used during 48 h incubation at 40 °C. In the current study, changes in pH, simple sugars, sucrose, oligosaccharides, and NSP contents during the enzymatic modification (CM+E) of CM were measured and compared to Control (CM) without enzymes addition or with the addition of bacteriostat sodium azide (CM+E+NaN3). The results showed that spontaneous fermentation occurred during incubation. After incubation, the pH of the slurry decreased, lactic acid was produced, phytate disappeared, and the concentration of simple sugars decreased substantially. The NSP of the slurry was progressively depolymerized by the enzyme blend. The chemical composition and nutritive value of enzymatically-modified CM (ECM) were evaluated. Ross 308 broilers were randomly assigned to 18 cages of six birds each for the standardized ileal amino acid digestibility (SIAAD) and nitrogen-corrected apparent metabolizable energy (AMEn) assay. A corn/soybean meal-based basal diet formulated to meet Ross 308 breeder recommendations and two test diets contained 70% of the basal diet and 30% of CM or ECM, respectively, were fed to Ross 308 from 13 to 17 d of age. No difference was observed between SIAAD of CM and ECM. The AMEn value of ECM was 2118.0 kcal/kg on a dry matter basis which was 30.9% greater (P < 0.05) than the CM.


Canola meal (CM) is a coproduct of canola oil production which is a valuable protein source for animal nutrition. Its nutritive value can be further enhanced through enzymatic treatment. This process also triggers the fermentation, which results in a decrease in slurry pH, production of lactic acid, disappearance of phytate, and reduction in simple sugars concentration. Moreover, the enzyme blend progressively depolymerized the nonstarch polysaccharides (NSP) of the slurry. No difference was observed between standardized ileal amino acid digestibility of CM and enzymatically-modified CM. The enzymatic modification improved the nitrogen-corrected apparent metabolizable energy of CM for broiler chickens by 30.9%.


Brassica napus , Chickens , Animals , Chickens/metabolism , Polygalacturonase/metabolism , Digestion , Animal Feed/analysis , Energy Metabolism , Brassica napus/chemistry , Diet/veterinary , Polysaccharides/metabolism , Nutritive Value , Amino Acids/metabolism , Animal Nutritional Physiological Phenomena
...