scholarly journals DEGRADASI DINDING SEL Phytophthora capsici OLEH ENZIM KARBOSI METIL SELULASE ASAL Trichoderma harzianum

2020 ◽  
Vol 9 (2) ◽  
pp. 74
Author(s):  
KARDEN MULYA ◽  
MELLY HARMEN

<p>Phytophthora capsici Leonian adalah patogen penyebab penyakit busuk pangkal batang lada (Piper nigrum L). Trichoderma harzianum Rifai merupakan agen hayati yang cfektif dan menyebabkan lisis miselia P. capsici. Penelitian ini bertujuan unluk mcngc(ahui peran enzim karboksimetilselulase (CMC-ase) yang diproduksi oleh T. harzianum dalam mendegradasi dinding sel P capsici. Penelitian terdiri atas tiga aktivitas yaitu (a) deteksi produksi enzim CMC-ase, (b) hidrolisis dinding sel P. capsici. dan (c) penggunaan siapan kasar dinding sel (SKDS) P. capsici oleh T. harzianum sebagai satu-satunya sumber karbon dalam media tumbuhnya Aktivitas enzim dideleksi secara kualitatif dengan membandingkan zona bening yang terbentuk pada medium karboksi metil selulosa (CMC) yang diperlakukan dengan satu tetcs iltrat kultur 7 harzianum dan diwarnai dengan larulan congo red, sedangkan aktivitas CMC-ase secara kuantitatif diukur sebagai nilai setara glukosa yang terlepas dari substrat setelah diinkubasi dengan ekstrak kasar CMC-ase. Enzim CMC-ase dickstrak dari kultur filtrat T. harzianum F.51 melalui pengendapan protein dengan 85% ammonium sulfat pada suhu 4°C diikuti dengan sentrifusi dan dialisis. Aktivitas spcsifik enzim tersebut dalam mendegradasi CMC (30,29 unif//g protein) lebih rendah dari aktivitas enzim selulase komersial (97.18 unit/^g protein). Enzim selulase komcrsial dan ekstrak enzim dari kultur 7 harzianum juga dapat menghidrolisis SKDS P. capsici N2 dengan aktivitas masing-masing 31.18 unit dan 19.26 unit. Isolat F-51 tumbuh dan menghasilkan aktivitas enzim serupa manakala karboksimclil selulosa pada media tumbuh diganti dengan SKDS sebagai sumber karbon tunggal Hasil ini menunjukkan bahwa CMC-ase berperan penting dalam mckanisme antagonis T. harzianum terhadap /' capsici. Penelitian lebih lanjut dalam mckanisme produksi enzim ini berpeluang untuk meningkatkan potensi agen hayati.</p><p>Kata kunci : Piper nigrum L., Trichoderma harzianum Rifai, Phytophthora capsici. karbosimctilsclulasc, agen hayati</p><p> </p><p><strong>ABSTRACT</strong></p><p><strong>Degradation of cell wall of Phytophthora capsici N2 by carboxy methyl cellulose &lt;;/ Trichoderma harzianum ES1</strong></p><p>Phytophthora capsici l-eonian is a causal agent of foot rot disease on black pepper (Piper nigrum L ). Trichoderma harzianum Rifai is an effective biocontrol agent and causes lyscs on P. capsici mycelium This experiment was aimed to study the role of carboxymethylccllulose (CMC- ase) produced by T. harzianum in degrading P. capsici cell wall. The experiment was composed in three activities (a) detection of the CMC-ase enzyme production, (b) degradation of P. capsici cell wall by crude extract of the enzyme, and (c) utilization of crude cell wall preparation (cwp) of P. capsici by T. harzianum as single carbon source in its growth medium CMC-ase activity was detected qualitatively on carboxymethylccllulose (CMC) medium, and quantitatively it was measured as glucose equivalent released from substrate after treated with crude extract of CMC-ase. CMC-ase was extracted from culture iltrate of T. harzianum F-51 by precipitation of protein with 85% ammonium sulphate at 4°C followed by dialysis with distilled water and liophyllizcd. Activity of the extracted enzyme on degradation of CMC (30.29 unil-'/jg protein) was lower than activity of commercial cellulose (97.18 united g protein) Commercial cclullosc and the extracted enzyme also degraded crude cell wall prepared (CWP) from P. capsici N2 as indicated with the presence of glucose equivalent released from CWP after incubation with the enzyme; with specific activity of 31.18 unit and 19.26 unit respectively. Trichoderma harzianum grown in medium suplemented with the crude cell wall of P. capsici as a single carbon source produced CMC-ase. Those results indicated that CMC-ase has important role on parasitism of T. harzianum on P. capsici Further investigation is required to elucidate mechanism of production of CMC-ase in T. harzianum for improvement of biocontrol activity of the fungus.</p><p>Key words: Piper nigrum L., Trichoderma harzianum Rifai, Phytophthora capsici, carboxymethylcellulosc, biocontrol</p>

1970 ◽  
Vol 16 (7) ◽  
pp. 629-634 ◽  
Author(s):  
Ronald W. Wilson

Several fungi were screened for biochemical and morphological responses to cellobiose, glucose, and maltose. All of the fungi contained an enzyme(s) capable of hydrolyzing an alkali-insoluble cell wall component from their respective hyphae. These enzymes as well as α- and β-glycosidases and N-acetyl-β-D-glucosaminidases were subject to regulation by carbohydrates in the medium. Cellobiose induced gross and microscopic morphological changes in the basidiomycetes but not in the ascomycetes or phycomycetes. Cellobiose also increased the specific activity of the wall-hydrolyzing enzymes in the basidiomycetes. The relationships between the carbon source, wall-hydrolyzing enzymes, and morphological responses are discussed.


Genes ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 1007
Author(s):  
Divya Kattupalli ◽  
Asha Sreenivasan ◽  
Eppurathu Vasudevan Soniya

Black pepper (Piper nigrum L.) is a prominent spice that is an indispensable ingredient in cuisine and traditional medicine. Phytophthora capsici, the causative agent of footrot disease, causes a drastic constraint in P. nigrum cultivation and productivity. To counterattack various biotic and abiotic stresses, plants employ a broad array of mechanisms that includes the accumulation of pathogenesis-related (PR) proteins. Through a genome-wide survey, eleven PR-1 genes that belong to a CAP superfamily protein with a caveolin-binding motif (CBM) and a CAP-derived peptide (CAPE) were identified from P. nigrum. Despite the critical functional domains, PnPR-1 homologs differ in their signal peptide motifs and core amino acid composition in the functional protein domains. The conserved motifs of PnPR-1 proteins were identified using MEME. Most of the PnPR-1 proteins were basic in nature. Secondary and 3D structure analyses of the PnPR-1 proteins were also predicted, which may be linked to a functional role in P. nigrum. The GO and KEGG functional annotations predicted their function in the defense responses of plant-pathogen interactions. Furthermore, a transcriptome-assisted FPKM analysis revealed PnPR-1 genes mapped to the P. nigrum-P. capsici interaction pathway. An altered expression pattern was detected for PnPR-1 transcripts among which a significant upregulation was noted for basic PnPR-1 genes such as CL10113.C1 and Unigene17664. The drastic variation in the transcript levels of CL10113.C1 was further validated through qRT-PCR and it showed a significant upregulation in infected leaf samples compared with the control. A subsequent analysis revealed the structural details, phylogenetic relationships, conserved sequence motifs and critical cis-regulatory elements of PnPR-1 genes. This is the first genome-wide study that identified the role of PR-1 genes during P. nigrum-P. capsici interactions. The detailed in silico experimental analysis revealed the vital role of PnPR-1 genes in regulating the first layer of defense towards a P. capsici infection in Panniyur-1 plants.


1999 ◽  
Vol 48 (1) ◽  
pp. 58-65 ◽  
Author(s):  
A. Sid Ahmed ◽  
C. Perez-Sanchez ◽  
C. Egea ◽  
M. E. Candela

2020 ◽  
Author(s):  
Divya Kattupalli ◽  
Asha Sriniva ◽  
Soniya E V

Abstract Background: Black pepper is a prominent spice which is an indispensable ingredient in culinary and traditional medicine. Phytophthora capsici, the causative agent of foot rot disease causes drastic constraint in black pepper cultivation and productivity. To counterattack various biotic and abiotic stresses plants employ a broad array of mechanisms one such includes the accumulation of pathogenesis-related (PR) proteins. Several studies have reported the role of PR-1 proteins in triggering the plant defenses during plant-oomycete interaction.Results: Through the genome-wide survey, eleven PR-1 genes that belongs to a CAP superfamily protein with Caveolin-Binding Motif (CBM) and CAP-derived peptide (CAPE) were identified from P. nigrum. Despite the critical functional domains, PnPR1 homologs differ in their signal peptide motifs, and core amino acid sequence composition in the functional protein domains. The GO, biological function analysis reveals their role in defense responses and response to biotic stimulus whereas the KEGG functional annotation predicted their function in the plant-pathogen interactions. Furthermore, transcriptome-assisted FPKM analysis revealed PnPR-1 genes mapped to P. nigrum - P. capsici interaction pathway. The differentially expressed pathogen-responsive PR-1 gene was validated through qRT-PCR. Subsequent analysis revealed the structural details, phylogenetic relationships, conserved sequence motifs and critical cis-regulatory elements of PnPR-1 genes.Conclusion: This is the first genome-wide study that identified the role of PR-1 genes during P. nigrum - P. capsici interactions. The detailed in silico experimental analysis revealed the vital role of PnPR-1 genes in regulating the first layer of defense towards P. capsici infection in Panniyur-1 plants.


1982 ◽  
Vol 152 (1) ◽  
pp. 298-305
Author(s):  
P Dehazya ◽  
R S Coles

To study the hemagglutinin of Fusobacterium nucleatum, methods were sought to solubilize and purify this component. When cells of F. nucleatum were ruptured by passage through a French press, the fragments lost virtually all ability to agglutinate human erythrocytes. Extraction of the fragments with 2% Triton X-100 for 30 min at 22 degrees C restored hemagglutinating activity (HA). Hemagglutination by these fragments could be inhibited by arginine, as can hemagglutination by intact bacteria. Treatment of active cell wall fragments with pronase and 2% Triton X-100-EDTA at 37 degrees C or with pronase and 0.1% Triton X-100-EDTA at pH 10.0 allowed recovery of solubilized HA. The former HA was inhibited by arginine (arg+) whereas the latter was not (arg-). Fractionation of the arg+ extract by preparative isoelectric focusing showed that HA was recovered from the gel sections having a pH between 4.5 and 5.5. Hemagglutination by this preparation was still arg+. Chromatography of this hemagglutinin on DEAE-Sephadex increased the specific activity to high levels with a loss of inhibition by arginine. A fraction from the DEAE-Sephadex column containing 10,700 HA units per mg of protein was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Solubilization at 22 degrees C before electrophoresis revealed three Coomassie blue-staining bands which migrated with apparent molecular weights of about 21,000, 38,000 and 60,000. When the same DEAE fraction was boiled in sodium dodecyl sulfate, electrophoresis revealed only one band with an apparent molecular weight of 21,000.


mBio ◽  
2020 ◽  
Vol 11 (5) ◽  
Author(s):  
Aílton Pereira da Costa Filho ◽  
Guilherme Thomaz Pereira Brancini ◽  
Patrícia Alves de Castro ◽  
Clara Valero ◽  
Jaire Alves Ferreira Filho ◽  
...  

ABSTRACT G-protein coupled receptors (GPCRs) are extracellular signaling receptors that sense environmental cues. Fungi sense their environment primarily through GPCR-mediated signaling pathways, which, in turn, regulate fungal development, metabolism, virulence, and mycotoxin biosynthesis. Aspergillus fumigatus is an important human pathogen that causes aspergillosis, a heterogeneous group of diseases that present a wide range of clinical manifestations. Here, we investigate in detail the role of the GPCRs GprM and GprJ in growth and gene expression. GprM and GprJ are important for melanin production and the regulation of the cell wall integrity (CWI) pathway. Overexpression of gprM and gprJ causes a 20 and 50% reduction in growth rate compared to the wild-type (WT) strain and increases sensitivity to cell wall-damaging agents. Phosphorylation of the CWI protein kinase MpkA is increased in the ΔgprM and ΔgprJ strains and decreased in the overexpression mutants compared to the WT strain. Furthermore, differences in cell wall polysaccharide concentrations and organization were observed in these strains. Transcriptome sequencing suggests that GprM and GprJ negatively regulate genes encoding secondary metabolites (SMs). Mass spectrometry analysis confirmed that the production of fumagillin, pyripyropene, fumigaclavine C, fumiquinazoline, and fumitremorgin is reduced in the ΔgprM and ΔgprJ strains, at least partially through the activation of MpkA. Overexpression of grpM also resulted in the regulation of many transcription factors, with AsgA predicted to function downstream of GprM and MpkA signaling. Finally, we show that the ΔgprM and ΔgprJ mutants are reduced in virulence in the Galleria mellonella insect model of invasive aspergillosis. IMPORTANCE A. fumigatus is the main etiological agent of invasive pulmonary aspergillosis, a life-threatening fungal disease that occurs in severely immunocompromised humans. Withstanding the host environment is essential for A. fumigatus virulence, and sensing of extracellular cues occurs primarily through G-protein coupled receptors (GPCRs) that activate signal transduction pathways, which, in turn, regulate fungal development, metabolism, virulence, and mycotoxin biosynthesis. The A. fumigatus genome encodes 15 putative classical GPCRs, with only three having been functionally characterized to date. In this work, we show that the two GPCRs GprM and GprJ regulate the phosphorylation of the mitogen-activated protein kinase MpkA and thus control the regulation of the cell wall integrity pathway. GprM and GprJ are also involved in the regulation of the production of the secondary metabolites fumagillin, pyripyropene, fumigaclavine C, fumiquinazoline, melanin, and fumitremorgin, and this regulation partially occurs through the activation of MpkA. Furthermore, GprM and GprJ are important for virulence in the insect model Galleria mellonella. This work therefore functionally characterizes two GPCRs and shows how they regulate several intracellular pathways that have been shown to be crucial for A. fumigatus virulence.


2009 ◽  
Vol 191 (21) ◽  
pp. 6584-6591 ◽  
Author(s):  
Anna Brzostek ◽  
Jakub Pawelczyk ◽  
Anna Rumijowska-Galewicz ◽  
Bozena Dziadek ◽  
Jaroslaw Dziadek

ABSTRACT It is expected that the obligatory human pathogen Mycobacterium tuberculosis must adapt metabolically to the various nutrients available during its cycle of infection, persistence, and reactivation. Cholesterol, which is an important part of the mammalian cytoplasmic membrane, is a potential energy source. Here, we show that M. tuberculosis grown in medium containing a carbon source other than cholesterol is able to accumulate cholesterol in the free-lipid zone of its cell wall. This cholesterol accumulation decreases the permeability of the cell wall for the primary antituberculosis drug, rifampin, and partially masks the mycobacterial surface antigens. Furthermore, M. tuberculosis was able to grow on mineral medium supplemented with cholesterol as the sole carbon source. Targeted disruption of the Rv3537 (kstD) gene inhibited growth due to inactivation of the cholesterol degradation pathway, as evidenced by accumulation of the intermediate, 9-hydroxy-4-androstene-3,17-dione. Our findings that M. tuberculosis is able to accumulate cholesterol in the presence of alternative nutrients and use it when cholesterol is the sole carbon source in vitro may facilitate future studies into the pathophysiology of this important deadly pathogen.


Sign in / Sign up

Export Citation Format

Share Document