scholarly journals Plant-derived antifungal agent poacic acid targets β-1,3-glucan

2015 ◽  
Vol 112 (12) ◽  
pp. E1490-E1497 ◽  
Author(s):  
Jeff S. Piotrowski ◽  
Hiroki Okada ◽  
Fachuang Lu ◽  
Sheena C. Li ◽  
Li Hinchman ◽  
...  
Keyword(s):  
Cell Wall ◽  
Antifungal Agent ◽  
Alternaria Solani ◽  
Phytophthora Sojae ◽  
Antifungal Compound ◽  
Fermentation Inhibitors ◽  
Lignocellulosic Hydrolysates ◽  
Renewable Biomass

A rise in resistance to current antifungals necessitates strategies to identify alternative sources of effective fungicides. We report the discovery of poacic acid, a potent antifungal compound found in lignocellulosic hydrolysates of grasses. Chemical genomics using Saccharomyces cerevisiae showed that loss of cell wall synthesis and maintenance genes conferred increased sensitivity to poacic acid. Morphological analysis revealed that cells treated with poacic acid behaved similarly to cells treated with other cell wall-targeting drugs and mutants with deletions in genes involved in processes related to cell wall biogenesis. Poacic acid causes rapid cell lysis and is synergistic with caspofungin and fluconazole. The cellular target was identified; poacic acid localized to the cell wall and inhibited β-1,3-glucan synthesis in vivo and in vitro, apparently by directly binding β-1,3-glucan. Through its activity on the glucan layer, poacic acid inhibits growth of the fungi Sclerotinia sclerotiorum and Alternaria solani as well as the oomycete Phytophthora sojae. A single application of poacic acid to leaves infected with the broad-range fungal pathogen S. sclerotiorum substantially reduced lesion development. The discovery of poacic acid as a natural antifungal agent targeting β-1,3-glucan highlights the potential side use of products generated in the processing of renewable biomass toward biofuels as a source of valuable bioactive compounds and further clarifies the nature and mechanism of fermentation inhibitors found in lignocellulosic hydrolysates.

In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

1978 ◽  
Vol 36 (2) ◽  
pp. 434-435
Author(s):  
D. Reis ◽  
B. Vian ◽  
J. C. Roland
Keyword(s):  
Cell Wall ◽  
Self Assembly ◽  
Plant Cell Wall ◽  
Higher Plants ◽  
Three Dimensional ◽  
Cytochemical Study ◽  
Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

scholarly journals Ibudilast Mitigates Delayed Bone Healing Caused by Lipopolysaccharide by Altering Osteoblast and Osteoclast Activity

2021 ◽  
Vol 22 (3) ◽  
pp. 1169
Author(s):  
Yuhan Chang ◽  
Chih-Chien Hu ◽  
Ying-Yu Wu ◽  
Steve W. N. Ueng ◽  
Chih-Hsiang Chang ◽  
...  
Keyword(s):  
Cell Wall ◽  
Bone Formation ◽  
Cancellous Bone ◽  
Bone Healing ◽  
Bone Bridge ◽  
Cell Wall Components ◽  
Osteoclast Activity ◽  
Wall Components

Bacterial infection in orthopedic surgery is challenging because cell wall components released after bactericidal treatment can alter osteoblast and osteoclast activity and impair fracture stability. However, the precise effects and mechanisms whereby cell wall components impair bone healing are unclear. In this study, we characterized the effects of lipopolysaccharide (LPS) on bone healing and osteoclast and osteoblast activity in vitro and in vivo and evaluated the effects of ibudilast, an antagonist of toll-like receptor 4 (TLR4), on LPS-induced changes. In particular, micro-computed tomography was used to reconstruct femoral morphology and analyze callus bone content in a femoral defect mouse model. In the sham-treated group, significant bone bridge and cancellous bone formation were observed after surgery, however, LPS treatment delayed bone bridge and cancellous bone formation. LPS inhibited osteogenic factor-induced MC3T3-E1 cell differentiation, alkaline phosphatase (ALP) levels, calcium deposition, and osteopontin secretion and increased the activity of osteoclast-associated molecules, including cathepsin K and tartrate-resistant acid phosphatase in vitro. Finally, ibudilast blocked the LPS-induced inhibition of osteoblast activation and activation of osteoclast in vitro and attenuated LPS-induced delayed callus bone formation in vivo. Our results provide a basis for the development of a novel strategy for the treatment of bone infection.

scholarly journals Efeito de extratos vegetais de plantas do Cerrado para controle de pinta-preta em tomateiro

2018 ◽  
Vol 44 (2) ◽  
pp. 189-192
Author(s):  
Bruna Fukumoto Kobayashi ◽  
Daniel Rufino Amaral
Keyword(s):  
Alternaria Solani

RESUMO A “Mancha de Alternaria” causada pelo fungo Alternaria solani é uma das principais e mais frequentes doenças que incidem na cultura do tomate. Manifesta-se nas hastes, caule e principalmente nas folhas, e em alta severidade. Causa desfolha e também pode provocar infecções nos frutos, tornando-os impróprios para comercialização. Para controle da doença, os defensivos sintéticos ainda são os mais utilizados. Visando a diminuição da toxicidade ao meio ambiente e à saúde humana, surge a busca pela utilização de produtos alternativos para o controle de doenças. O objetivo do trabalho foi avaliar o efeito de extratos vegetais para o controle de Alternaria solani na cultura do tomateiro: in vivo e in vitro. O experimento foi conduzido em duas etapas: 1- in vivo (em casa de vegetação em sistema hidropônico) e 2- in vitro (em laboratório). Os tratamentos utilizados na primeira etapa foram: 1- Testemunha (sem aplicação); 2- Extrato de Assa peixe; 3- Extrato de Aroeirinha; 4- Extrato de Pata de Vaca do Cerrado; 5- Extrato de Murici, sendo estes na concentração de 10% do extrato diluído em água e outra testemunha no qual foi aplicado um fungicida (Piraclostrobina). O delineamento experimental foi em blocos ao acaso com quatro repetições. Na segunda etapa, o experimento foi conduzido em delineamento inteiramente casualizado, sendo os mesmos tratamentos da primeira, exceto o tratamento comercial. Observou-se que os extratos a base de Aroeirinha e Assa Peixe, proporcionaram controle de mancha de alternaria em plantas de tomate no experimento in vivo. Já para o experimento in vitro, pode-se observar que o extrato de Murici e Aroeirinha diminuíram o crescimento micelial do fungo.

Spilanthol as a promising antifungal alkylamide for the treatment of vulvovaginal candidiasis

2021 ◽  
Author(s):  
Rodrigo L Fabri ◽  
Jhamine C O Freitas ◽  
Ari S O Lemos ◽  
Lara M Campos ◽  
Irley O M Diniz ◽  
...  
Keyword(s):  
Cell Wall ◽  
Candida Albicans ◽  
Antifungal Activity ◽  
Cell Membrane ◽  
Multidrug Resistant ◽  
Fungal Strain ◽  
Vulvovaginal Candidiasis ◽  
Biofilm Matrix

Abstract Spilanthol is a bioactive alkylamide from the native Amazon plant species, Acmella oleracea. However, antifungal activities of spilanthol and its application to the therapeutic treatment of candidiasis remains to be explored. This study sought to evaluate the in vitro and in vivo antifungal activity of spilanthol previously isolated from A. oleracea (spilanthol(AcO)) against Candida albicans ATCC® 10231™, a multidrug-resistant fungal strain. Microdilution methods were used to determine inhibitory and fungicidal concentrations of spilanthol(AcO). In planktonic cultures, the fungal growth kinetics, yeast cell metabolic activity, cell membrane permeability and cell wall integrity were investigated. The effect of spilanthol(AcO) on the proliferation and adhesion of fungal biofilms was evaluated by whole slide imaging and scanning electron microscopy. The biochemical composition of the biofilm matrix was also analyzed. In parallel, spilanthol(AcO) was tested in vivo in an experimental vulvovaginal candidiasis model. Our in vitro analyses in C. albicans planktonic cultures detected a significant inhibitory effect of spilanthol(AcO), which affects both yeast cell membrane and cell wall integrity, interfering with the fungus growth. C. albicans biofilm proliferation and adhesion, as well as, carbohydrates and DNA in biofilm matrix were reduced after spilanthol(AcO) treatment. Moreover, infected rats treated with spilanthol(AcO) showed consistent reduction of both fungal burden and inflammatory processes compared to the untreated animals. Altogether, our findings demonstrated that spilanthol(AcO) is an bioactive compound against planktonic and biofilm forms of a multidrug resistant C. albicans strain. Furthermore, spilanthol(AcO) can be potentially considered for therapeutical treatment of vulvovaginal candidiasis caused by C. albicans. Lay Abstract This study sought to evaluate the antifungal activity of spilanthol against Candida albicans ATCC® 10 231™, a multidrug-resistant fungal strain. Our findings demonstrated that spilanthol(AcO) can be potentially considered for therapeutical treatment of vulvovaginal candidiasis caused by C. albicans.

scholarly journals Keefektifan Bakteri dan Khamir Asal Air Rendaman Kompos dalam Menekan Perkembangan Penyakit Bercak Coklat (Alternaria solani Sorr.) pada Tomat

Agrikultura ◽  
2020 ◽  
Vol 31 (1) ◽  
pp. 52
Author(s):  
Noor Istifadah ◽  
Putu Ghita Novilaressa ◽  
Fitri Widiantini ◽  
Sri Hartati
Keyword(s):  
Alternaria Solani

Penyakit bercak coklat yang disebabkan oleh jamur Alternaria solani Sorr. merupakan salah satu penyakit penting pada tanaman tomat. Cara pengendalian penyakit bercak coklat yang biasa dilakukan adalah dengan penyemprotan fungisida sintetik. Mengingat berbagai dampak negatif dari penggunaan pestisida yang terus-menerus, maka perlu dikembangakan cara pengendalian ramah lingkungan seperti pengendalian secara biologi. Bakteri dan jamur merupakan mikrob yang berpotensi sebagai agens biokontrol penyakit tanaman. Salah satu sumber dari agens antagonis patogen tanaman adalah air rendaman kompos. Paper ini mendiskusikan hasil penelitian yang mengevaluasi kemampuan bakteri mikrob yang diisolasi dari air rendaman kompos berbahan dasar kotoran sapi dan domba untuk menghambat pertumbuhan A. solani in vitro dan menekan penyakit yang disebabkan patogen tersebut pada buah dan tanaman tomat. Percobaan secara in vitro menggunakan Rancangan Acak Lengkap, sementara pengujian pada buah dan tanaman tomat menggunakan Rancangan Acak Kelompok. Isolasi mikrob dari air rendaman kompos berbahan dasar kotoran sapi dan domba menghasilkan 35 isolat, yang mana 11 isolat (enam isolat bakteri dan lima isolat khamir) dapat menghambat pertumbuhan A. solani secara in vitro sebesar 79,3%-84,2% dengan zona hambat sebesar 0,0-28,3 mm. Pada pengujian secara in vivo, lima isolat non-patogenik (dua isolat bakteri dan tiga isolat khamir) dapat menekan penyakit bercak coklat pada buah tomat sebesar 100% dan pada daun tomat sebesar 77,5%-98,1%. Isolat-isolat ini berpotensi untuk dikembangkan lebih lanjut sebagai agens biokontrol penyakit bercak coklat pada tanaman tomat.

The yeast acid phosphatase can enter the secretory pathway without its N-terminal signal sequence

1987 ◽  
Vol 7 (9) ◽  
pp. 3306-3314
Author(s):  
S Silve ◽  
M Monod ◽  
A Hinnen ◽  
R Haguenauer-Tsapis
Keyword(s):  
Cell Wall ◽  
Acid Phosphatase ◽  
Gene Product ◽  
Secretory Pathway ◽  
Signal Sequence ◽  
In Vitro Mutagenesis ◽  
Heterologous System ◽  
Pho5 Gene

The repressible Saccharomyces cerevisiae acid phosphatase (APase) coded by the PHO5 gene is a cell wall glycoprotein that follows the yeast secretory pathway. We used in vitro mutagenesis to construct a deletion (delta SP) including the entire signal sequence and four amino acids of the mature sequence of APase. An APase-deficient yeast strain was transformed with a high-copy-number plasmid carrying the PHO5/delta SP gene. When expressed in vivo, the PHO5/delta SP gene product accumulated predominantly as an inactive, unglycosylated form located inside the cell. A large part of this unglycosylated precursor underwent proteolytic degradation, but up to 30% of it was translocated, core glycosylated, and matured by the addition of mannose residues, before reaching the cell wall. It appears, therefore, that the signal sequence is important for efficient translocation and core glycosylation of yeast APase but that it is not absolutely necessary for entry of the protein into the yeast secretory pathway. mRNA obtained by in vitro transcription of PHO5 and PHO5/delta SP genes were translated in vitro in the presence of either reticulocyte lysate and dog pancreatic microsomes or yeast lysate and yeast microsomes. The PHO5 gene product was translocated and core glycosylated in the heterologous system and less efficiently in the homologous system. We were not able to detect any translocation or glycosylation of PHO5/delta SP gene product in the heterologous system, but a very small amount of core suppression of glycosylated material could be evidenced in the homologous system.

Abstract 3: Apolipoprotein A-I Inhibits Streptococcal Cell Wall-Induced Arthritis in the Rat in an ABCA1-dependent Manner

2013 ◽  
Vol 33 (suppl_1) ◽  
Author(s):  
Ben J Wu ◽  
Kwok L Ong ◽  
Sudichhya Shrestha ◽  
Kang Chen ◽  
Philip J Barter ◽  
...  
Keyword(s):  
Cell Wall ◽  
Inflammatory Cytokine ◽  
Density Lipoprotein ◽  
Joint Inflammation ◽  
Chronic Inflammatory Disease ◽  
Dependent Manner ◽  
Tlr2 Expression ◽  
Streptococcal Cell Wall

Introduction. Arthritis is a chronic inflammatory disease characterized by joint inflammation and destruction, reduced high-density lipoprotein (HDL) levels, and increased cardiovascular risk. Objective To determine if apolipoprotein (apo) A-I, the main HDL apolipoprotein, prevents joint inflammation in arthritis. Methods and Results In vivo: Arthritis was induced in female Lewis rats with a single 15 mg/kg intraperitoneal streptococcal cell wall peptidoglycan-polysaccharide (PG-PS) injection and quantified as a combined forepaw and hindpaw inflammation score. Arthritis progressed from an initial, acute phase of joint inflammation during the first 4 days post-PG-PS administration to remission by day 8, followed by chronic joint inflammation up to sacrifice at day 21. Two intravenous infusions of lipid-free apoA-I (8 mg/kg) 24 h pre- and 24 h post-PG-PS injection reduced the acute and chronic joint inflammation by 63±9% at day 3 and by 61±8% at day 21. Infusion of apoA-I at days 7, 9 and 11 post-PG-PS injection reduced the chronic response by 43±11% at day 21. ApoA-I infusions at 24 h prior to and at days 1, 7, 9, 11 post-PG-PS injection reduced joint inflammation by 61±5% at day 3 and by 90±5% at day 21 (p<0.05 for all vs saline infusion). These beneficial effects of apoA-I were accompanied by a reduced inflammatory white blood cell count, reduced pro-inflammatory cytokine levels in synovial fluid, and reduced macrophage accumulation, toll-like receptor 2 (TLR2) and inflammatory cytokine expression in synovial tissue. In vitro: Human monocyte-derived macrophages (HMDMs) were pre-incubated with lipid-free apoA-I, then stimulated with PG-PS (20 μg/mL). Pre-incubation with apoA-I inhibited PG-PS-induced TLR2 and MyD88, a TLR2 adapter protein, expression. Nuclear factor-κB activation and pro-inflammatory cytokine production were also attenuated. These anti-inflammatory effects of apoA-I were abolished in HMDMs transfected with ATP-binding cassette transporter 1 (ABCA1) siRNA. Conclusions These findings establish that apoA-I attenuates PG-PS induced arthritis in the rat. These effects may involve ABCA-1 and inhibition of TLR2 expression and activation.

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