Paeonol Disrupts the Integrity of Aspergillus flavus Cell Walls via Releasing Surface Proteins, Inhibiting the Biosynthesis of β-1,3-Glucan and Promoting the Degradation of Chitin, and an Identification of Cell Surface Proteins

Paeonol can effectively inhibit Aspergillus flavus (A. flavus) via damaging cell walls. In this work, paeonol treatment remarkably destroyed both the outer amorphous layer and the inner fibrous layer of cell walls. Furthermore, FT-IR and XPS characterization showed that OH functional groups were altered and proteins in the outer layer were released. According to proteomic analysis, 605 proteins have been identified and annotated. The activities of β-1,3-glucan synthase and chitinase were prohibited and promoted, respectively, by paeonol treatment, however, the activities of β-1,3-glucanase and chitin synthase were not influenced. QRT-PCR results suggested that FKSP, CHIIII, and CHIV genes might be the antifungal targets of paeonol. In addition, paeonol can effectively restrain the pathogenicity of A. flavus on peanut butter. This study provided a new elucidation on the mode of action of paeonol against cell walls of A. flavus, facilitating the application of paeonol in the preservation of agricultural products.

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STUDIES ON BACTERIOPHAGES OF HEMOLYTIC STREPTOCOCCI

Journal of Experimental Medicine ◽

10.1084/jem.106.3.365 ◽

1957 ◽

Vol 106 (3) ◽

pp. 365-384 ◽

Cited By ~ 45

Author(s):

Richard M. Krause

Keyword(s):

Cell Wall ◽

Hyaluronic Acid ◽

Cell Walls ◽

Receptor Site ◽

Surface Proteins ◽

Phage Antibody ◽

Group A ◽

Phage Receptor ◽

Hyaluronic Acid Capsule ◽

Isolated Cell

The host ranges of bacteriophages for group A, types 1, 6, 12, and 25 and group C streptococci have been determined. The findings indicate that the susceptibility to these phages is primarily a group-specific phenomenon, although it is modified by several factors such as the hyaluronic acid capsule, lysogeny, and possibly the presence of surface proteins. Phage antibody studies indicate that while the group A phages are antigenically related, they are distinct from the group C phage. This is in agreement with the observation that group A phages are not specific for their homologous streptococcal types. The purified group C carbohydrate inactivates group C phage but not the group A phages, thus suggesting that the carbohydrate, a component of the cell wall, may serve as the phage receptor site. It has not been possible to inactivate the group A phages with group A carbohydrate. Phage lysis of groups A and C streptococci is accompanied by fragmentation of the cell wall since the C carbohydrate has been identified serologically and chemically in the supernate of centrifuged lysates. The immediate lysis of groups A and C hemolytic streptococci and their isolated cell walls by an accesory heat-labile lytic factor in fresh group C lysates is also described.

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Effect of Aspergillus flavus Fungal Elicitor on the Production of Terpenoid Indole Alkaloids in Catharanthus roseus Cambial Meristematic Cells

Molecules ◽

10.3390/molecules23123276 ◽

2018 ◽

Vol 23 (12) ◽

pp. 3276

Author(s):

Chuxin Liang ◽

Chang Chen ◽

Pengfei Zhou ◽

Lv Xu ◽

Jianhua Zhu ◽

...

Keyword(s):

Suspension Culture ◽

Aspergillus Flavus ◽

Catharanthus Roseus ◽

Indole Alkaloids ◽

Fungal Elicitor ◽

Control Group ◽

Terpenoid Indole Alkaloids ◽

Meristematic Cells ◽

Qrt Pcr ◽

Induction Process

This study reported the inducing effect of Aspergillus flavus fungal elicitor on biosynthesis of terpenoid indole alkaloids (TIAs) in Catharanthus roseus cambial meristematic cells (CMCs) and its inducing mechanism. According to the results determined by HPLC and HPLC-MS/MS, the optimal condition of the A. flavus elicitor was as follows: after suspension culture of C. roseus CMCs for 6 day, 25 mg/L A. flavus mycelium elicitor were added, and the CMC suspensions were further cultured for another 48 h. In this condition, the contents of vindoline, catharanthine, and ajmaline were 1.45-, 3.29-, and 2.14-times as high as those of the control group, respectively. Transcriptome analysis showed that D4H, G10H, GES, IRS, LAMT, SGD, STR, TDC, and ORCA3 were involved in the regulation of this induction process. The results of qRT-PCR indicated that the increasing accumulations of vindoline, catharanthine, and ajmaline in C. roseus CMCs were correlated with the increasing expression of the above genes. Therefore, A. flavus fungal elicitor could enhance the TIA production of C. roseus CMCs, which might be used as an alternative biotechnological resource for obtaining bioactive alkaloids.

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A multivariate statistical analysis approach to highlight molecular processes in plant cell walls through ATR FT-IR microspectroscopy: The role of the α-expansin PhEXPA1 in Petunia hybrida

Vibrational Spectroscopy ◽

10.1016/j.vibspec.2012.11.010 ◽

2013 ◽

Vol 65 ◽

pp. 36-43 ◽

Cited By ~ 16

Author(s):

F. Monti ◽

R. Dell’Anna ◽

A. Sanson ◽

M. Fasoli ◽

M. Pezzotti ◽

...

Keyword(s):

Statistical Analysis ◽

Multivariate Statistical Analysis ◽

Cell Walls ◽

Petunia Hybrida ◽

Plant Cell Walls ◽

Molecular Processes ◽

Multivariate Statistical ◽

Ft Ir ◽

Ir Microspectroscopy

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Surface proteins of two aflatoxin-producing isolates of Aspergillus flavus and Aspergillus parasiticus mycelia. 1. A comparative immunochemical profile

Journal of Agricultural and Food Chemistry ◽

10.1021/jf00021a027 ◽

1992 ◽

Vol 40 (9) ◽

pp. 1610-1612 ◽

Cited By ~ 2

Author(s):

Joseph N. Neucere ◽

Abul H. J. Ullah ◽

Thomas E. Cleveland

Keyword(s):

Aspergillus Flavus ◽

Aspergillus Parasiticus ◽

Surface Proteins

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A combined FT-IR microscopy and principal component analysis on softwood cell walls

Carbohydrate Polymers ◽

10.1016/s0144-8617(03)00013-4 ◽

2003 ◽

Vol 52 (4) ◽

pp. 449-453 ◽

Cited By ~ 55

Author(s):

Ritsuko Hori ◽

Junji Sugiyama

Keyword(s):

Principal Component Analysis ◽

Cell Walls ◽

Principal Component ◽

Component Analysis ◽

Ir Microscopy ◽

Ft Ir

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Effect of benomyl and diazinon on acquired azole resistance in Aspergillus flavus and expression of mdr1 and cyp51c genes

Current Medical Mycology ◽

10.18502/cmm.5.2.1158 ◽

2019 ◽

Author(s):

Maryam Akbari Dana ◽

Seyed Jamal Hashemi ◽

Roshanak Daei Ghazvini ◽

Sadegh Khodavesi ◽

Mona Modiri ◽

...

Keyword(s):

Drug Resistance ◽

Amphotericin B ◽

Aspergillus Flavus ◽

Morphological Changes ◽

Agricultural Products ◽

Sensitive Species ◽

Agricultural Pesticides ◽

Expression Of Genes ◽

Resistant Strains

Background and Purpose: Aspergillus flavus is an important pathogen in immunodeficient patients. Due to the abundance of this fungus in nature, fungicides are commonly used to preserve and maintain agricultural products. Long-term exposure to these pesticides can lead to the induction of drug resistance in this fungus. Materials and Methods: For the purpose of the study, 10 strains of A. flavus ATCC 204304 were cultured in benomyl and diazinon pesticides at the concentrations of 62.5, 125, 250.500, 750, 1000, 1500, 2000, and 2500 mg/L in nine steps. Morphological changes and resistance to voriconazole, itraconazole, and amphotericin B were evaluated at the end of each step. Subsequently, changes in the expression of mdr1 and cyp51C genes were studied in the strains showing drug resistance. Results: The results showed that during the nine stages of the adjacency of strains with benomyl and diazinon at different concentrations, resistance to voriconazole, itraconazole, and amphotericin B in these toxins increased by 30% and 10%, respectively. In addition, the microscopic examination of resistant strains revealed the absence of sporulation, and only mycelium was found. Macroscopically, the color of the colonies changed from green to white. Furthermore, the investigation of the expression of mdr1 and cyp51c genes in these strains showed a decrease and increase in adjacency with diazinon and benomyl, respectively. Conclusion: As the findings indicated, exposure to agricultural pesticides can lead to the incidence of morphological changes and resistance to amphotericin B, itraconazole, and voriconazole in the sensitive species of A. flavus by altering the expression of genes involved in drug resistance.

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Impact of Silver Nanoparticles on Gene Expression in Aspergillus Flavus Producer Aflatoxin B1

Open Access Macedonian Journal of Medical Sciences ◽

10.3889/oamjms.2018.117 ◽

2018 ◽

Vol 6 (4) ◽

pp. 600-605 ◽

Cited By ~ 2

Author(s):

Mohamed Mahmoud Deabes ◽

Wagdy Khalil Bassaly Khalil ◽

Ashraf Gamil Attallah ◽

Tarek Ahmed El-Desouky ◽

Khayria Mahmoud Naguib

Keyword(s):

Silver Nanoparticles ◽

Aspergillus Flavus ◽

Aflatoxin B1 ◽

Inhibitory Effect ◽

Aflatoxin Biosynthesis ◽

Qrt Pcr ◽

Methyltransferase Gene ◽

Polymerase Chain ◽

Yeast Extract Sucrose ◽

Quantitative Pcr Assay

AIM: In this study, we evaluated the effect of silver nanoparticles (AgNPs) on the production of aflatoxin B1 (AFB1) through assessment the transcription activity of aflatoxin biosynthesis pathway genes in Aspergillus flavus ATCC28542.MATERIAL AND METHODS: The mRNAs were quantitative by Real Time-polymerase chain reaction (qRT-PCR) of A. flavus grown in yeast extract sucrose (YES) medium containing AgNPs. Specific primers that are involved in the AFB1 biosynthesis which highly specific to A. flavus, O-methyltransferase gene (omt-A), were designed and used to detect the fungus activity by quantitative PCR assay. The AFB1 production (from A. flavus growth) which effected by AgNPs were measured in YES medium by high-pressure liquid chromatography (HPLC).RESULTS: The AFB1 produced by A. flavus have the highest reduction with 1.5 mg -100 ml of AgNPs were added in media those records 88.2%, 67.7% and 83.5% reduction by using AgNP HA1N, AgNP HA2N and AgNP EH, respectively. While on mycelial growth give significantly inhibitory effect. These results have been confirmed by qRT-PCR which showed that culture of A. flavus with the presence of AgNPs reduced the expression levels of omt-A gene.CONCLUSION: Based on the results of the present study, AgNPs inhibit growth and AFB1 produced by Aspergillus flavus ATCC28542. This was confirmed through RT-PCR approach showing the effect of AgNPs on omt-A gene involved in aflatoxin biosynthesis.

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