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1.
J Cell Sci ; 135(5)2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33912961

RESUMO

Septins colocalize with membrane sterol-rich regions and facilitate recruitment of cell wall synthases during wall remodeling. We show that null mutants missing an Aspergillus nidulans core septin present in hexamers and octamers (ΔaspAcdc11, ΔaspBcdc3 or ΔaspCcdc12) are sensitive to multiple cell wall-disturbing agents that activate the cell wall integrity MAPK pathway. The null mutant missing the octamer-exclusive core septin (ΔaspDcdc10) showed similar sensitivity, but only to a single cell wall-disturbing agent and the null mutant missing the noncore septin (ΔaspE) showed only very mild sensitivity to a different single agent. Core septin mutants showed changes in wall polysaccharide composition and chitin synthase localization. Mutants missing any of the five septins resisted ergosterol-disrupting agents. Hexamer mutants showed increased sensitivity to sphingolipid-disrupting agents. Core septins mislocalized after treatment with sphingolipid-disrupting agents, but not after ergosterol-disrupting agents. Our data suggest that the core septins are involved in cell wall integrity signaling, that all five septins are involved in monitoring ergosterol metabolism, that the hexamer septins are required for sphingolipid metabolism and that septins require sphingolipids to coordinate the cell wall integrity response.


Assuntos
Aspergillus nidulans , Septinas , Aspergillus nidulans/metabolismo , Parede Celular/metabolismo , Metabolismo dos Lipídeos , Septinas/genética , Septinas/metabolismo , Esfingolipídeos/metabolismo
2.
Food Chem ; 367: 130708, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34352692

RESUMO

In this study, we explored structural differences of five commercial samples of yeast ß-glucan. Samples were assayed for their ß-glucan content and the yeast storage carbohydrate, glycogen. The ß-glucan content ranged from 74% to 86%, the glycogen content varied from 0 to 20%. The linkage pattern of each sample was measured by the partially methylated alditol acetate method. This method showed that the samples varied from 1.9% to 9.2% branching. The side chain length distribution for each sample was analyzed by an alkaline degradation assay followed by ion chromatography. The side length distributions of the samples were shown to be similar. The samples were also analyzed by FT-IR and 1HNMR spectroscopy but it was difficult to derive quantitative differences in the samples by these methods. Our findings confirm that each proprietary source of yeast ß-glucan has a unique purity profile, branching, and linkage patterns that determine the chemical structure and composition.


Assuntos
Saccharomyces cerevisiae , beta-Glucanas , Parede Celular , Glucanos , Saccharomyces cerevisiae/genética , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Appl Microbiol Biotechnol ; 105(20): 7997-8007, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34596723

RESUMO

Agaricus bisporus is the most widely cultivated edible mushroom in the world. Strain quality has an important influence on the yield of A. bisporus, with strains that exhibit aging being a common problem during cultivation. However, little is known about the aging mechanisms of A. bisporus strain. In this study, the normal A. bisporus As2796 strain was compared to the aging A. bisporus As2796Y strain (which was previously discovered during cultivation). In the aging As2796Y mycelia, the mycelial growth rate and fruiting body yield were decreased and the chitin level and cell wall thickness were increased. Additionally, intracellular vacuoles increased, there was cytoplasmic shrinkage, and the sterol level which stabilizes the cell membrane decreased, which led to cytoplasmic outflow and the exudation of a large amount of yellow water from the mycelia. Additionally, there was increased electrolyte leakage. Furthermore, gas chromatography-mass spectrometry (GC/MS) was used to profile the metabolic changes in the aging As2796Y mycelia compared to the normal As2796 mycelia. A total of 52 differential metabolites were identified (75% were downregulated and 25% were upregulated in As2796Y). The reduction of many metabolites decreased the mycelial viability and the ability to maintain cell stability. Overall, this study is the first to report on the morphologic and metabolic changes in aged A. bisporus mycelia, which will aid future research on the mechanisms underlying A. bisporus mycelial aging.Key points• Aging of Agaricus bisporus strains will greatly reduce the fruiting body yield.• Aging of Agaricus bisporus strains can significantly change the cell structure of mycelia.• Many metabolites in the mycelium of aging spawn As2796Y significantly changed.


Assuntos
Agaricus , Ascomicetos , Parede Celular , Micélio
4.
BMC Genomics ; 22(1): 638, 2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34479506

RESUMO

BACKGROUND: LncRNAs are extensively involved in plant biological processes. However, the lack of a comprehensive lncRNA landscape in moso bamboo has hindered the molecular study of lncRNAs. Moreover, the role of lncRNAs in secondary cell wall (SCW) biosynthesis of moso bamboo is elusive. RESULTS: For comprehensively identifying lncRNA throughout moso bamboo genome, we collected 231 RNA-Seq datasets, 1 Iso-Seq dataset, and 1 full-length cDNA dataset. We used a machine learning approach to improve the pipeline of lncRNA identification and functional annotation based on previous studies and identified 37,009 lncRNAs in moso bamboo. Then, we established a network of potential lncRNA-coding gene for SCW biosynthesis and identified SCW-related lncRNAs. We also proposed that a mechanism exists in bamboo to direct phenylpropanoid intermediates to lignin or flavonoids biosynthesis through the PAL/4CL/C4H genes. In addition, we identified 4 flavonoids and 1 lignin-preferred genes in the PAL/4CL/C4H gene families, which gained implications in molecular breeding. CONCLUSIONS: We provided a comprehensive landscape of lncRNAs in moso bamboo. Through analyses, we identified SCW-related lncRNAs and improved our understanding of lignin and flavonoids biosynthesis.


Assuntos
Parede Celular , Redes Reguladoras de Genes , Poaceae , RNA Longo não Codificante , Parede Celular/genética , Regulação da Expressão Gênica de Plantas , Poaceae/genética , RNA Longo não Codificante/genética , RNA de Plantas/genética
6.
J Hazard Mater ; 416: 125894, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492832

RESUMO

The chemistry of root cell wall of rice could be changed by inoculation of arbuscular mycorrhizal fungi (AMF). Hydroponic experiments were conducted to investigate the roles of such changes on cadmium (Cd) uptake and distribution in rice. Results showed that inoculation of AM fungus Rhizophagus intraradices (RI) significantly enhanced (p < 0.05) shoot biomass, plant height and root length of rice, and decreased Cd concentration in shoot and root under Cd stress. Moreover, Cd in root was mainly found in pectin and hemicellulose 1 (HC1) components of root cell wall. Inoculation of RI increased the levels of pectin, HC1 and lignin content, accompanied by the increments of L-phenylalanine ammonia-lyase (PAL) and pectin methylesterase (PME) activities. Results of Fourier transform infrared spectroscopy further showed that more hydroxyl and carboxyl groups in root cell wall were observed in mycorrhizal treatment, compared with control. This study demonstrates that cell wall components could be the locations for Cd fixation, which reduced Cd transportation from root to shoot. Inoculation of AMF may remodel root cell wall biosynthesis and affect the characteristics of Cd fixation. The entering and fixing mechanisms should be further studied.


Assuntos
Micorrizas , Oryza , Poluentes do Solo , Cádmio/análise , Parede Celular/química , Fungos , Raízes de Plantas/química , Poluentes do Solo/análise
7.
J Anim Sci ; 99(9)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34468760

RESUMO

The main objective of this study was to evaluate the effect of peripartal administration of a commercially available nonspecific immune stimulant (mycobacterium cell wall fraction; MCWF [Amplimune, NovaVive Inc., Napanee, ON, Canada]) on the incidence of disease during early lactation and subsequent fertility of dairy cows. A second objective was to characterize the dynamics of circulating white blood cells (WBC) and metabolic markers following treatment administration. Cows in an United States Department of Agriculture (USDA) organic-certified dairy herd were blocked by parity and, based on sequential calving dates, randomly assigned to receive two injections (5 mL s.c.) of either a placebo (saline solution) as a control (CON; n = 71) or MCWF (n = 65) at enrollment (7 d before expected calving) and within 24 h after calving. Blood samples were collected from a subsample of the study population (MCWF = 16; CON = 18) for WBC count at enrollment, at day 2 post enrollment, and at days 1, 3, 7, and 14 after calving. Serum fatty acids, beta-hydroxybutyrate, and Ca concentrations were determined at days 1 and 7 postpartum (MCWF = 21; CON = 21). Main outcome variables included incidence risk of peripartal and early lactation health disorders and pregnancy at first artificial insemination (AI), at 100, and at 150 days in milk (DIM). In addition, the average daily milk yield up to 90 DIM and death and live culling before 305 DIM were compared. Treatment effects were assessed using multivariable logistic regression, time-to-event analyses, and repeated measures analysis of variance (ANOVA). A treatment effect on the incidence risk of some of the health disorders in the study was established. Incidence risk of metritis and clinical mastitis <28 DIM was smaller in MCWF than in CON cows (36.9% vs. 50.7% and 6.3% vs. 19.7%, respectively). On the contrary, the incidence risk of respiratory disease <28 DIM was smaller in CON (0%) than in MCWF (7.7%). Reproductive performance of multiparous cows was affected by MCWF administration: pregnancy at first AI and pregnancy at 100 and 150 DIM were greater in MCWF than in CON (35.6% vs. 19.2%; 51.1% vs. 25.0%; and 64.4% vs. 40.4%, respectively). Overall, median intervals from calving to pregnancy were 90 vs. 121 d in MCWF and CON cows, respectively. No treatment effects on the dynamics of circulating WBC or in postpartum metabolic status were established. No differences for milk yield or for the proportion of cows that survived up to 305 DIM were determined, although cows in MCWF left the herd earlier than cows in CON. In conclusion, incidence risks of metritis and mastitis in early lactation were smaller in cows receiving MCWF, whereas the incidence risk of respiratory disease was smaller in CON. Fertility significantly improved in MCWF compared with CON cows. As this study was performed in an organic-certified dairy, specific health and reproductive management practices may affect the external validity of the current findings.


Assuntos
Doenças dos Bovinos , Mycobacterium , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Parede Celular , Feminino , Fertilidade , Lactação , Leite , Período Pós-Parto , Gravidez , Reprodução
8.
Analyst ; 146(19): 5843-5847, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34570849

RESUMO

Instead of using the lipid II substrate that requires prior labelling with a radioactive isotope or fluorophore to probe the formation of peptidoglycan in bacterial transglycosylation, the released undecaprenyl pyrophosphate (UPP) product is quantitatively measured either using a terpyridine-zinc fluorescence turn-on sensor or simply by the second-order scattering effect of the in situ formed UPP-calcium complex. Both the assay methods are utilized to identify moenomycin A as a potent transglycosylase inhibitor with a consistent IC50 value.


Assuntos
Bactérias , Peptidoglicano , Parede Celular
9.
Plant Sci ; 311: 110984, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34482904

RESUMO

Perennial woody plants undergo a period of dormancy from the beginning of autumn until the end of spring. Whereas the molecular and physiological events that characterize dormancy release of buds have been described in detail, those occurring in woody tissues underneath the buds are mostly unknown. To bridge this gap, the mRNA populations of cane segments located underneath the bud were analyzed at bud dormancy (E-L 1) and at bud burst (E-L 4). They revealed an important reprogramming of gene expression suggesting that cell division, cell wall metabolism and the mobilization of sugars are the main metabolic and cellular events occurring in cane woody tissues at bud burst. Also, the upregulation of several genes of sugar metabolism, encoding starch- and sucrose-degrading enzymes and sugar transporters, correlates with the decrease in starch and soluble sugars in woody tissues concomitant with increased sucrose synthase and α-amylolytic biochemical activities. The latter is likely due to the VviAMY2 gene that encodes a functional α-amylase as observed after its heterologous expression in yeast. Taken together, these results are consistent with starch and sugar mobilization in canes being primarily involved in grapevine secondary growth initiation and supporting the growth of the emerging bud.


Assuntos
Parede Celular/metabolismo , Dormência de Plantas/genética , Dormência de Plantas/fisiologia , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/genética , Vitis/crescimento & desenvolvimento , Vitis/genética , Transporte Biológico/genética , Transporte Biológico/fisiologia , Divisão Celular/genética , Divisão Celular/fisiologia , Parede Celular/genética , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Portugal , RNA Mensageiro/metabolismo , Açúcares/metabolismo , alfa-Amilases/metabolismo
10.
Plant Sci ; 311: 111015, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34482918

RESUMO

In the current climate change scenario, understanding crops' physiological performance under water shortage is crucial to overcome drought periods. Although the implication of leaf water relations maintaining leaf turgor and stomatal functioning under water deprivation has been suggested, the relationships between photosynthesis and osmotic and elastic adjustments remain misunderstood. Similarly, only few studies in dicotyledonous analysed how changes in cell wall composition affected photosynthesis and leaf water relations under drought. To induce modifications in photosynthesis, leaf water relations and cell wall composition, Hordeum vulgare and Triticum aestivum were subjected to different water regimes: control (CL, full irrigation), moderate and severe water deficit stress (Mod WS and Sev WS, respectively). Water shortage decreased photosynthesis mainly due to stomatal conductance (gs) declines, being accompanied by reduced osmotic potential at full turgor (πo) and increased bulk modulus of elasticity (ε). Whereas both species enhanced pectins when intensifying water deprivation, species-dependent adjustments occurred for cellulose and hemicelluloses. From these results, we showed that πo and ε influenced photosynthesis, particularly, gs. Furthermore, the (Cellulose+Hemicelluloses)/Pectins ratio determined ε and mesophyll conductance (gm) in grasses, presenting the lowest pectins content within angiosperms. Thus, we highlight the relevance of cell wall composition regulating grasses physiology during drought acclimation.


Assuntos
Parede Celular/química , Desidratação/fisiopatologia , Secas , Hordeum/fisiologia , Fotossíntese/fisiologia , Folhas de Planta/fisiologia , Triticum/fisiologia , Água/metabolismo , Mudança Climática , Produtos Agrícolas/fisiologia
11.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34544876

RESUMO

Aspergillus fumigatus is a human opportunistic pathogen showing emerging resistance against a limited repertoire of antifungal agents available. The GTPase Rho1 has been identified as an important regulator of the cell wall integrity signaling pathway that regulates the composition of the cell wall, a structure that is unique to fungi and serves as a target for antifungal compounds. Rom2, the guanine nucleotide exchange factor to Rho1, contains a C-terminal citron homology (CNH) domain of unknown function that is found in many other eukaryotic genes. Here, we show that the Rom2 CNH domain interacts directly with Rho1 to modulate ß-glucan and chitin synthesis. We report the structure of the Rom2 CNH domain, revealing that it adopts a seven-bladed ß-propeller fold containing three unusual loops. A model of the Rho1-Rom2 CNH complex suggests that the Rom2 CNH domain interacts with the Rho1 Switch II motif. This work uncovers the role of the Rom2 CNH domain as a scaffold for Rho1 signaling in fungal cell wall biosynthesis.


Assuntos
Aspergillus fumigatus/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Parede Celular/fisiologia , Proteínas Fúngicas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Aspergillus fumigatus/genética , Aspergillus fumigatus/crescimento & desenvolvimento , Fatores de Transcrição de Zíper de Leucina Básica/química , Fatores de Transcrição de Zíper de Leucina Básica/genética , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/genética , Conformação Proteica , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais , Proteínas rho de Ligação ao GTP/química , Proteínas rho de Ligação ao GTP/genética
12.
Int J Mol Sci ; 22(17)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34502129

RESUMO

Size control is a fundamental question in biology, showing incremental complexity in plants, whose cells possess a rigid cell wall. The phytohormone auxin is a vital growth regulator with central importance for differential growth control. Our results indicate that auxin-reliant growth programs affect the molecular complexity of xyloglucans, the major type of cell wall hemicellulose in eudicots. Auxin-dependent induction and repression of growth coincide with reduced and enhanced molecular complexity of xyloglucans, respectively. In agreement with a proposed function in growth control, genetic interference with xyloglucan side decorations distinctly modulates auxin-dependent differential growth rates. Our work proposes that auxin-dependent growth programs have a spatially defined effect on xyloglucan's molecular structure, which in turn affects cell wall mechanics and specifies differential, gravitropic hypocotyl growth.


Assuntos
Glucanos/metabolismo , Ácidos Indolacéticos/metabolismo , Células Vegetais/metabolismo , Desenvolvimento Vegetal , Fenômenos Fisiológicos Vegetais , Xilanos/metabolismo , Arabidopsis/fisiologia , Parede Celular/metabolismo , Imunofluorescência , Regulação da Expressão Gênica de Plantas , Glucanos/química , Ervilhas/fisiologia , Transdução de Sinais , Xilanos/química
13.
Int J Mol Sci ; 22(18)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34576062

RESUMO

Drought is a severe environmental stress that exerts negative effects on plant growth. In trees, drought leads to reduced secondary growth and altered wood anatomy. The mechanisms underlying wood stress adaptation are not well understood. Here, we investigated the physiological, anatomical, hormonal, and transcriptional responses of poplar to strong drought. Drought-stressed xylem was characterized by higher vessel frequencies, smaller vessel lumina, and thicker secondary fiber cell walls. These changes were accompanied by strong increases in abscisic acid (ABA) and antagonistic changes in salicylic acid in wood. Transcriptional evidence supported ABA biosynthesis and signaling in wood. Since ABA signaling activates the fiber-thickening factor NST1, we expected upregulation of the secondary cell wall (SCW) cascade under stress. By contrast, transcription factors and biosynthesis genes for SCW formation were down-regulated, whereas a small set of cellulose synthase-like genes and a huge array of genes involved in cell wall modification were up-regulated in drought-stressed wood. Therefore, we suggest that ABA signaling monitors normal SCW biosynthesis and that drought causes a switch from normal to "stress wood" formation recruiting a dedicated set of genes for cell wall biosynthesis and remodeling. This proposition implies that drought-induced changes in cell wall properties underlie regulatory mechanisms distinct from those of normal wood.


Assuntos
Reguladores de Crescimento de Plantas/genética , Populus/genética , Transcrição Genética , Madeira/genética , Parede Celular/genética , Secas , Regulação da Expressão Gênica de Plantas/genética , Populus/crescimento & desenvolvimento , Estresse Fisiológico/genética , Ativação Transcricional/genética , Madeira/crescimento & desenvolvimento , Xilema/genética , Xilema/crescimento & desenvolvimento
14.
Front Cell Infect Microbiol ; 11: 679792, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34568085

RESUMO

Binding to plasminogen (Plg) enables bacteria to associate with and invade host tissues. The cell wall protein PbsP significantly contributes to the ability of group B streptococci, a frequent cause of invasive infection, to bind Plg. Here we sought to identify the molecular regions involved in the interactions between Plg and PbsP. The K4 Kringle domain of the Plg molecule was required for binding of Plg to whole PbsP and to a PbsP fragment encompassing a region rich in methionine and lysine (MK-rich domain). These interactions were inhibited by free L-lysine, indicating the involvement of lysine binding sites in the Plg molecule. However, mutation to alanine of all lysine residues in the MK-rich domain did not decrease its ability to bind Plg. Collectively, our data identify a novel bacterial sequence that can interact with lysine binding sites in the Plg molecule. Notably, such binding did not require the presence of lysine or other positively charged amino acids in the bacterial receptor. These data may be useful for developing alternative therapeutic strategies aimed at blocking interactions between group B streptococci and Plg.


Assuntos
Lisina , Plasminogênio , Sítios de Ligação , Parede Celular/metabolismo , Lisina/metabolismo , Plasminogênio/metabolismo , Ligação Proteica , Streptococcus agalactiae
15.
FASEB J ; 35(9): e21778, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34383971

RESUMO

As a result of the relatively few available antifungals and the increasing frequency of resistance to them, the development of novel antifungals is increasingly important. The plant natural product poacic acid (PA) inhibits ß-1,3-glucan synthesis in Saccharomyces cerevisiae and has antifungal activity against a wide range of plant pathogens. However, the mode of action of PA is unclear. Here, we reveal that PA specifically binds to ß-1,3-glucan, its affinity for which is ~30-fold that for chitin. Besides its effect on ß-1,3-glucan synthase activity, PA inhibited the yeast glucan-elongating activity of Gas1 and Gas2 and the chitin-glucan transglycosylase activity of Crh1. Regarding the cellular response to PA, transcriptional co-regulation was mediated by parallel activation of the cell-wall integrity (CWI) and high-osmolarity glycerol signaling pathways. Despite targeting ß-1,3-glucan remodeling, the transcriptional profiles and regulatory circuits activated by caspofungin, zymolyase, and PA differed, indicating that their effects on CWI have different mechanisms. The effects of PA on the growth of yeast strains indicated that it has a mode of action distinct from that of echinocandins, suggesting it is a unique antifungal agent.


Assuntos
Antifúngicos/farmacologia , Parede Celular/efeitos dos fármacos , Ácidos Cumáricos/farmacologia , Glicerol/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Estilbenos/farmacologia , Transcrição Genética/efeitos dos fármacos , beta-Glucanas/farmacologia , Caspofungina/farmacologia , Parede Celular/genética , Parede Celular/metabolismo , Quitina/farmacologia , Equinocandinas/farmacologia , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/genética , Concentração Osmolar , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transcrição Genética/genética
16.
BMC Genomics ; 22(1): 589, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34348651

RESUMO

BACKGROUND: The Botryosphaeriaceae are important plant pathogens, but also have the ability to establish asymptomatic infections that persist for extended periods in a latent state. In this study, we used comparative genome analyses to shed light on the genetic basis of the interactions of these fungi with their plant hosts. For this purpose, we characterised secreted hydrolytic enzymes, secondary metabolite biosynthetic gene clusters and general trends in genomic architecture using all available Botryosphaeriaceae genomes, and selected Dothideomycetes genomes. RESULTS: The Botryosphaeriaceae genomes were rich in carbohydrate-active enzymes (CAZymes), proteases, lipases and secondary metabolic biosynthetic gene clusters (BGCs) compared to other Dothideomycete genomes. The genomes of Botryosphaeria, Macrophomina, Lasiodiplodia and Neofusicoccum, in particular, had gene expansions of the major constituents of the secretome, notably CAZymes involved in plant cell wall degradation. The Botryosphaeriaceae genomes were shown to have moderate to high GC contents and most had low levels of repetitive DNA. The genomes were not compartmentalized based on gene and repeat densities, but genes of secreted enzymes were slightly more abundant in gene-sparse regions. CONCLUSION: The abundance of secreted hydrolytic enzymes and secondary metabolite BGCs in the genomes of Botryosphaeria, Macrophomina, Lasiodiplodia, and Neofusicoccum were similar to those in necrotrophic plant pathogens and some endophytes of woody plants. The results provide a foundation for comparative genomic analyses and hypotheses to explore the mechanisms underlying Botryosphaeriaceae host-plant interactions.


Assuntos
Ascomicetos , Ascomicetos/genética , Parede Celular , Endófitos , Família Multigênica , Filogenia , Plantas
17.
J Agric Food Chem ; 69(33): 9571-9584, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34378924

RESUMO

Fungal cell wall synthesizing enzymes or remodeling enzymes represent key factors for the interaction of plant pathogen and antifungal agents, which are regarded as potential biocontrol agents. In this study, a novel endo-ß-1,3-glucanase from Magnaporthe oryzae was expressed and characterized. The expression of MoGluB was significantly upregulated after 2 days of liquid culture and 48 h after infection, indicating that it may be involved in cell wall reconstitution. Purified MoGluB exhibited high activity on insoluble ß-glucans, with a specific activity of 8.18 U/mg toward yeast glucan at pH 9.0 and 50 °C. MoGluB hydrolyzed pachymaran and yeast glucan into oligosaccharides dominated by laminaripentaose, suggesting that it is an endo-ß-1,3-glucanase. Incubation of 8 µg of MoGluB with 106 spores/mL resulted in the inhibition of conidial germination and appressorium formation of M. oryzae, illustrating effective biocontrol activity. Hydrolysates of pachymaran induced the expression of defense genes restricting M. oryzae infection in rice plants, indicating an immunostimulatory effect of MoGluB hydrolysates.


Assuntos
Ascomicetos , Magnaporthe , Oryza , Parede Celular , Proteínas Fúngicas/genética , Doenças das Plantas
18.
J Microbiol ; 59(9): 840-847, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34383247

RESUMO

Endolysin, a peptidoglycan hydrolase derived from bacteriophage, has been suggested as an alternative antimicrobial agent. Many endolysins on staphylococcal phages have been identified and applied extensively against Staphylococcus spp. Among them, LysK-like endolysin, a well-studied staphylococcal endolysin, accounts for most of the identified endolysins. However, relatively little interest has been paid to LysKunlike endolysin and a few of them has been characterized. An endolysin LysSAP33 encoded on bacteriophage SAP33 shared low homology with LysK-like endolysin in sequence by 41% and domain composition (CHAP-unknown CBD). A green fluorescence assay using a fusion protein for LysSAP33_CBD indicated that the CBD domain (157-251 aa) was bound to the peptidoglycan of S. aureus. The deletion of LysSAP33_CBD at the C-terminal region resulted in a significant decrease in lytic activity and efficacy. Compared to LysK-like endolysin, LysSAP33 retained its lytic activity in a broader range of temperature, pH, and NaCl concentrations. In addition, it showed a higher activity against biofilms than LysK-like endolysin. This study could be a helpful tool to develop our understanding of staphylococcal endolysins not belonging to LysK-like endolysins and a potential biocontrol agent against biofilms.


Assuntos
Endopeptidases/metabolismo , Fagos de Staphylococcus/enzimologia , Staphylococcus aureus/virologia , Proteínas Virais/metabolismo , Sequência de Aminoácidos , Parede Celular/metabolismo , Parede Celular/virologia , Endopeptidases/química , Endopeptidases/genética , Peptidoglicano/metabolismo , Alinhamento de Sequência , Fagos de Staphylococcus/química , Fagos de Staphylococcus/genética , Fagos de Staphylococcus/fisiologia , Staphylococcus aureus/metabolismo , Proteínas Virais/química , Proteínas Virais/genética
19.
Nat Commun ; 12(1): 4975, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404791

RESUMO

Plant cell wall hydrolysates contain not only sugars but also substantial amounts of acetate, a fermentation inhibitor that hinders bioconversion of lignocellulose. Despite the toxic and non-consumable nature of acetate during glucose metabolism, we demonstrate that acetate can be rapidly co-consumed with xylose by engineered Saccharomyces cerevisiae. The co-consumption leads to a metabolic re-configuration that boosts the synthesis of acetyl-CoA derived bioproducts, including triacetic acid lactone (TAL) and vitamin A, in engineered strains. Notably, by co-feeding xylose and acetate, an enginered strain produces 23.91 g/L TAL with a productivity of 0.29 g/L/h in bioreactor fermentation. This strain also completely converts a hemicellulose hydrolysate of switchgrass into 3.55 g/L TAL. These findings establish a versatile strategy that not only transforms an inhibitor into a valuable substrate but also expands the capacity of acetyl-CoA supply in S. cerevisiae for efficient bioconversion of cellulosic biomass.


Assuntos
Parede Celular/metabolismo , Engenharia Metabólica , Polissacarídeos/metabolismo , Saccharomyces cerevisiae/metabolismo , Acetilcoenzima A/metabolismo , Biomassa , Reatores Biológicos , Fermentação , Lignina , Pironas/metabolismo , Saccharomyces cerevisiae/genética , Vitamina A/metabolismo , Xilose/metabolismo
20.
BMC Plant Biol ; 21(1): 384, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34416854

RESUMO

BACKGROUND: C. sinensis is an important economic crop with fluoride over-accumulation in its leaves, which poses a serious threat to human health due to its leaf consumption as tea. Recently, our study has indicated that cell wall proteins (CWPs) probably play a vital role in fluoride accumulation/detoxification in C. sinensis. However, there has been a lack in CWP identification and characterization up to now. This study is aimed to characterize cell wall proteome of C. sinensis leaves and to develop more CWPs related to stress response. A strategy of combined cell wall proteomics and N-glycoproteomics was employed to investigate CWPs. CWPs were extracted by sequential salt buffers, while N-glycoproteins were enriched by hydrophilic interaction chromatography method using C. sinensis leaves as a material. Afterwards all the proteins were subjected to UPLC-MS/MS analysis. RESULTS: A total of 501 CWPs and 195 CWPs were identified respectively by cell wall proteomics and N-glycoproteomics profiling with 118 CWPs in common. Notably, N-glycoproteomics is a feasible method for CWP identification, and it can enhance CWP coverage. Among identified CWPs, proteins acting on cell wall polysaccharides constitute the largest functional class, most of which might be involved in cell wall structure remodeling. The second largest functional class mainly encompass various proteases related to CWP turnover and maturation. Oxidoreductases represent the third largest functional class, most of which (especially Class III peroxidases) participate in defense response. As expected, identified CWPs are mainly related to plant cell wall formation and defense response. CONCLUSION: This was the first large-scale investigation of CWPs in C. sinensis through cell wall proteomics and N-glycoproteomics. Our results not only provide a database for further research on CWPs, but also an insight into cell wall formation and defense response in C. sinensis.


Assuntos
Camellia sinensis/química , Parede Celular/química , Fluoretos/análise , Glicoproteínas/análise , Folhas de Planta/química , Proteínas de Plantas/análise , China , Produtos Agrícolas/química , Proteômica
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