scholarly journals Biological control of collar rot disease with broad-spectrum antifungal bacteria associated with groundnut

2005 ◽  
Vol 51 (2) ◽  
pp. 123-132 ◽  
Author(s):  
G Krishna Kishore ◽  
S Pande ◽  
A R Podile
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Broad Spectrum ◽  
Fungal Pathogens ◽  
Crown Rot ◽  
Cercospora Arachidicola ◽  
Collar Rot ◽  
Rhizoctonia Bataticola ◽  
Culture Filtrates ◽  
Necrotrophic Fungi ◽  
Biotrophic Fungi

Bacteria associated with 6 habitats of groundnut were evaluated for their broad-spectrum antifungal activity and suppression of collar rot (Aspergillus niger) of groundnut. Three hundred and ninety-three strains were tested against 8 fungal pathogens of groundnut including 5 necrotrophic fungi, Aspergillus flavus, A. niger, Rhizoctonia bataticola, Rhizoctonia solani, and Sclerotium rolfsii, and 3 biotrophic fungi, Cercospora arachidicola, Phaeoisariopsis personata, and Puccinia arachidis. Pseudomonas sp. GRS 175, Pseudomonas aeruginosa GPS 21, GSE 18, GSE 19, and GSE 30, and their cell-free culture filtrates were highly antagonistic to all the test fungi. The cell-free culture filtrates of these bacteria were fungicidal and induced mycelial deformations including hyphal bulging and vacuolization in necrotrophic fungi. The cell-free culture filtrates at 10% (v/v) concentration significantly inhibited the spore germination of biotrophic fungi. In the greenhouse, P. aeruginosa GSE 18 emerged as an effective biocontrol agent of collar rot closely followed by P. aeruginosa GSE 19. The bacterium applied as a seed treatment reduced the pre-emergence rotting and postemergence wilting by >60%. Pseudomonas aeruginosa GSE 18 effectively colonized the groundnut rhizosphere, both in native and in A. niger infested potting mixtures. Ninety-day-old peat formulation of P. aeruginosa GSE 18 had biocontrol ability comparable with the midlog-phase cells. Pseudomonas aeruginosa GSE 18, tolerant to thiram, in combination with the fungicide had an improved collar rot control. The present study was a successful attempt in selection of broad-spectrum and fungicide tolerant biocontrol agents that can be a useful component of integrated management of collar rot.Key words: Arachis, biocontrol, crown rot, peanut.

The Study of Bacillus Subtils Antimicrobial Activity on Some of the Pathological Isolates

2019 ◽  
Vol 9 (02) ◽  
Author(s):  
Hussein A Kadhum ◽  
Thualfakar H Hasan2
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Activity ◽  
Bacillus Subtilis ◽  
Bacterial Growth ◽  
Broad Spectrum ◽  
Inhibitory Activity ◽  
Bacterial Pathogens ◽  
Inhibitory Ability ◽  
Selection Of

The study involved the selection of two isolates from Bacillus subtilis to investigate their inhibitory activity against some bacterial pathogens. B sub-bacteria were found to have a broad spectrum against test bacteria such as Staphylococcus aureus and Pseudomonas aeruginosa. They were about 23-30 mm and less against Klebsiella sp. The sensitivity of some antibodies was tested on the test samples. The results showed that the inhibitory ability of bacterial growth in the test samples using B. subtilis extract was more effective than the antibiotics used.

scholarly journals Genomic analysis of carbapenem resistant Pseudomonas aeruginosa ST143 clone showing susceptibility to broad spectrum cephalosporins

2021 ◽  
Author(s):  
Ana Paula Streling ◽  
Rodrigo Cayô ◽  
Carolina S. Nodari ◽  
Luiz G.P. Almeida ◽  
Fernanda F. Santos ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Broad Spectrum ◽  
Genomic Analysis ◽  
Carbapenem Resistant

scholarly journals Biological control of strawberry crown rot, root rot and grey mould by the beneficial fungus Aureobasidium pullulans

BioControl ◽  
2021 ◽  
Author(s):  
Mudassir Iqbal ◽  
Maha Jamshaid ◽  
Muhammad Awais Zahid ◽  
Erik Andreasson ◽  
Ramesh R. Vetukuri ◽  
...  
Keyword(s):  
Root Rot ◽  
Fungal Pathogens ◽  
Aureobasidium Pullulans ◽  
Grey Mould ◽  
Lesion Size ◽  
Plant Diseases ◽  
Crown Rot ◽  
Whole Plants

AbstractUtilization of biocontrol agents is a sustainable approach to reduce plant diseases caused by fungal pathogens. In the present study, we tested the effect of the candidate biocontrol fungus Aureobasidium pullulans (De Bary) G. Armaud on strawberry under in vitro and in vivo conditions to control crown rot, root rot and grey mould caused by Phytophthora cactorum (Lebert and Cohn) and Botrytis cinerea Pers, respectively. A dual plate confrontation assay showed that mycelial growth of P. cactorum and B. cinerea was reduced by 33–48% when challenged by A. pullulans as compared with control treatments. Likewise, detached leaf and fruit assays showed that A. pullulans significantly reduced necrotic lesion size on leaves and disease severity on fruits caused by P. cactorum and B. cinerea. In addition, greenhouse experiments with whole plants revealed enhanced biocontrol efficacy against root rot and grey mould when treated with A. pullulans either in combination with the pathogen or pre-treated with A. pullulans followed by inoculation of the pathogens. Our results demonstrate that A. pullulans is an effective biocontrol agent to control strawberry diseases caused by fungal pathogens and can be an effective alternative to chemical-based fungicides.

scholarly journals Changes in the Use of Broad-Spectrum Antibiotics after Cefepime Shortage: a Time Series Analysis

2011 ◽  
Vol 56 (2) ◽  
pp. 989-994 ◽  
Author(s):  
C. Plüss-Suard ◽  
A. Pannatier ◽  
C. Ruffieux ◽  
A. Kronenberg ◽  
K. Mühlemann ◽  
...  
Keyword(s):  
Time Series ◽  
Pseudomonas Aeruginosa ◽  
Broad Spectrum ◽  
Interrupted Time Series ◽  
Antibiotic Policy ◽  
Content Type ◽  
Broad Spectrum Antibiotics ◽  
Before And After ◽  
Alternative Antibiotic ◽  
The Impact

ABSTRACTThe original cefepime product was withdrawn from the Swiss market in January 2007 and replaced by a generic 10 months later. The goals of the study were to assess the impact of this cefepime shortage on the use and costs of alternative broad-spectrum antibiotics, on antibiotic policy, and on resistance ofPseudomonas aeruginosatoward carbapenems, ceftazidime, and piperacillin-tazobactam. A generalized regression-based interrupted time series model assessed how much the shortage changed the monthly use and costs of cefepime and of selected alternative broad-spectrum antibiotics (ceftazidime, imipenem-cilastatin, meropenem, piperacillin-tazobactam) in 15 Swiss acute care hospitals from January 2005 to December 2008. Resistance ofP. aeruginosawas compared before and after the cefepime shortage. There was a statistically significant increase in the consumption of piperacillin-tazobactam in hospitals with definitive interruption of cefepime supply and of meropenem in hospitals with transient interruption of cefepime supply. Consumption of each alternative antibiotic tended to increase during the cefepime shortage and to decrease when the cefepime generic was released. These shifts were associated with significantly higher overall costs. There was no significant change in hospitals with uninterrupted cefepime supply. The alternative antibiotics for which an increase in consumption showed the strongest association with a progression of resistance were the carbapenems. The use of alternative antibiotics after cefepime withdrawal was associated with a significant increase in piperacillin-tazobactam and meropenem use and in overall costs and with a decrease in susceptibility ofP. aeruginosain hospitals. This warrants caution with regard to shortages and withdrawals of antibiotics.

scholarly journals Identifikasi Pseudomonas aeruginosa dan tes sensitivitas siprofloksasin pada abses periodontal Identification of Pseudomonas aeruginosa and sensitivity test of ciprofloxacin on periodontal abcess

2011 ◽  
Vol 10 (3) ◽  
pp. 151 ◽  
Author(s):  
Irene E. Rieuwpassa ◽  
Muliaty Yunus ◽  
I Wayan Suka Arsana
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Observational Study ◽  
Broad Spectrum ◽  
Host Resistance ◽  
Dna Gyrase ◽  
Common Type ◽  
Sensitivity Test ◽  
Bacterial Dna ◽  
Resistance Factors ◽  
Synthetic Drug

Periodontitis is a common type of periodontal disease caused by expansion of the early stages of gingivalinflammation. Expansion of inflammation to the tissue structures supporting the teeth can be modified by thepathogenic ability of plaque or host resistance factors. A total of 200 different bacteria have been identified on theplaque. Resistance to antimicrobials can be natural because the microbes develop mechanisms to defendthemselves. Ciprofloxacin is a synthetic drug of the second generation quinolones derivatives. Mechanism of itsaction is to inhibit the activity of bacterial DNA gyrase, which is bactericidal with a broad spectrum against Grampositiveor negative. This observational study identified P. aeruginosa and sensitivity test was performed tociprofloxacin in periodontal abscesses. Study conducted in 23 patients with periodontal abscess. Of those,Pseudomonas was acquired for 8 samples and 4 of them was resistant to ciprofloxacin.

scholarly journals Developing Cyclic Peptomers as Broad-Spectrum Gram negative Bacterial Type III Secretion System Inhibitors

2020 ◽  
Author(s):  
Hanh N. Lam ◽  
Tannia Lau ◽  
Adam Lentz ◽  
Jessica Sherry ◽  
Alejandro Cabrera-Cortez ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Chlamydia Trachomatis ◽  
Broad Spectrum ◽  
Type Iii Secretion ◽  
Type Iii Secretion System ◽  
Secretion System ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
Type Iii ◽  
Bacterial Type

ABSTRACTAntibiotic resistant bacteria are an emerging global health threat. New antimicrobials are urgently needed. The injectisome type III secretion system (T3SS), required by dozens of Gram-negative bacteria for virulence but largely absent from non-pathogenic bacteria, is an attractive antimicrobial target. We previously identified synthetic cyclic peptomers, inspired by the natural product phepropeptin D, that inhibit protein secretion through the Yersinia Ysc and Pseudomonas aeruginosa Psc T3SSs, but do not inhibit bacterial growth. Here we describe identification of an isomer, 4EpDN, that is two-fold more potent (IC50 4 μM) than its parental compound. Furthermore, 4EpDN inhibited the Yersinia Ysa and the Salmonella SPI-1 T3SSs, suggesting that this cyclic peptomer has broad efficacy against evolutionarily distant injectisome T3SSs. Indeed, 4EpDN strongly inhibited intracellular growth of Chlamydia trachomatis in HeLa cells, which requires the T3SS. 4EpDN did not inhibit the unrelated Twin arginine translocation (Tat) system, nor did it impact T3SS gene transcription. Moreover, although the injectisome and flagellar T3SSs are evolutionarily and structurally related, the 4EpDN cyclic peptomer did not inhibit secretion of substrates through the Salmonella flagellar T3SS, indicating that cyclic peptomers broadly but specifically target the injestisome T3SS. 4EpDN reduced the number of T3SS basal bodies detected on the surface of Y. enterocolitica, as visualized using a fluorescent derivative of YscD, an inner membrane ring with low homology to flagellar protein FliG. Collectively, these data suggest that cyclic peptomers specifically inhibit the injectisome T3SS from a variety of Gram-negative bacteria, possibly by preventing complete T3SS assembly.IMPORTANCETraditional antibiotics target both pathogenic and commensal bacteria, resulting in a disruption of the microbiota, which in turn is tied to a number of acute and chronic diseases. The bacterial type III secretion system (T3SS) is an appendage used by many bacterial pathogens to establish infection, but is largely absent from commensal members of the microbiota. In this study, we identify a new derivative of the cyclic peptomer class of T3SS inhibitors. These compounds inhibit the T3SS of the nosocomial ESKAPE pathogen Pseudomonas aeruginosa and enteropathogenic Yersinia and Salmonella. The impact of cyclic peptomers is specific to the T3SS, as other bacterial secretory systems are unaffected. Importantly, cyclic peptomers completely block replication of Chlamydia trachomatis, the causative agent of genital, eye, and lung infections, in human cells, a process that requires the T3SS. Therefore, cyclic peptomers represent promising virulence blockers that can specifically disarm a broad spectrum of Gram-negative pathogens.

Time to First Culture Positivity for Gram-Negative Rods Resistant to Ceftriaxone in Critically Ill Adults

2020 ◽  
Vol 36 (1) ◽  
pp. 51-57
Author(s):  
Kevin G. Buell ◽  
Jonathan D. Casey ◽  
Michael J. Noto ◽  
Todd W. Rice ◽  
Matthew W. Semler ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Critically Ill ◽  
Broad Spectrum ◽  
Research Question ◽  
Blood Cultures ◽  
Optimal Timing ◽  
Gram Negative ◽  
Broad Spectrum Antibiotics ◽  
Critically Ill Adults ◽  
Ill Adults

Background: The optimal timing for the de-escalation of broad-spectrum antibiotics with activity against Pseudomonas aeruginosa and resistant Gram-negative rods (GNRs) in critically ill adults remains unknown. Research Question: We tested the hypothesis that cultures will identify GNRs that ultimately demonstrate resistance to ceftriaxone within 48 hours, potentially allowing safe de-escalation at this time point. Study Design and Methods: We conducted a secondary analysis of data from the Isotonic Solutions and Major Adverse Renal Events Trial: a pragmatic, cluster-randomized, multiple-crossover trial comparing balanced crystalloids versus saline for intravenous fluid administration in 15,802 critically ill adults at 5 intensive care units (ICUs) at Vanderbilt University Medical Center in Nashville, TN, USA. The primary endpoint was the time-to-positivity of respiratory and blood cultures that ultimately demonstrated growth of GNRs resistant to ceftriaxone. Multivariable logistic regression modeling was used to examine risk factors for the growth of cultures after 48 hours. Results: A total of 524 respiratory cultures had growth of GNRs, of which 284 (54.2%) had resistance to ceftriaxone. A total of 376 blood cultures grew GNRs, of which 70 (18.6%) had resistance to ceftriaxone. At 48 hours, 87% of respiratory cultures and 85% of blood cultures that ultimately grew GNRs resistant to ceftriaxone had demonstrated growth. Age, gender, predicted risk of inpatient mortality and prior use of antibiotics did not predict the growth of cultures after 48 hours. Interpretation: Among a cohort of critically ill adults, 13% of respiratory cultures and 15% of blood cultures that ultimately grew GNRs resistant to ceftriaxone did not demonstrate growth until at least 48 hours after collection. Further work is needed to determine the ideal time for critically ill adults to de-escalate from broad-spectrum antibiotics targeting Pseudomonas aeruginosa and extended-spectrum β-lactamase-producing gram-negative pathogens.

scholarly journals In VitroEvaluation of Novel Compounds against Selected Resistant Pseudomonas aeruginosa Isolates

2011 ◽  
Vol 56 (3) ◽  
pp. 1646-1649 ◽  
Author(s):  
Seth T. Housman ◽  
Christina Sutherland ◽  
David P. Nicolau
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Broad Spectrum ◽  
Large Subunit ◽  
Multidrug Resistant ◽  
Content Type ◽  
Bacterial Ribosome ◽  
Multidrug Resistant Pathogens

ABSTRACTWe describe the activities of RX-P763, RX-P766, RX-P770, RX-P792, RX-P793, and RX-P808 against strains of resistantPseudomonas aeruginosa. These compounds target the large subunit of the bacterial ribosome and have broad-spectrum activities against multidrug-resistant pathogens. All compounds demonstratedin vitroactivity againstP. aeruginosa, with MIC90values of 4 to 8 μg/ml (range, 0.5 to 64). These novel compounds had narrow MIC distributions and maintained activity despite resistance phenotypes to other commonly utilized agents.

Toxic culture filtrates produced byCalonectria ilicicola, causal agent of red crown rot of soybean

2001 ◽  
Vol 29 (2) ◽  
pp. 115-123 ◽  
Author(s):  
K. D. Kim ◽  
J. S. Russin ◽  
J. P. Snow ◽  
K. E. Damann
Keyword(s):  
Causal Agent ◽  
Crown Rot ◽  
Culture Filtrates ◽  
Red Crown Rot ◽  
Toxic Culture

scholarly journals The Urinary Antibiotic 5-Nitro-8-Hydroxyquinoline (Nitroxoline) Reduces the Formation and Induces the Dispersal of Pseudomonas aeruginosa Biofilms by Chelation of Iron and Zinc

2012 ◽  
Vol 56 (11) ◽  
pp. 6021-6025 ◽  
Author(s):  
A. Sobke ◽  
M. Klinger ◽  
B. Hermann ◽  
S. Sachse ◽  
S. Nietzsche ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Broad Spectrum ◽  
Viable Cell ◽  
Antibiofilm Activity ◽  
Content Type ◽  
Cell Counts ◽  
Iron And Zinc ◽  
Chelation Of Iron

ABSTRACTSince cations have been reported as essential regulators of biofilm, we investigated the potential of the broad-spectrum antimicrobial and cation-chelator nitroxoline as an antibiofilm agent. Biofilm mass synthesis was reduced by up to 80% at sub-MIC nitroxoline concentrations inPseudomonas aeruginosa, and structures formed were reticulate rather than compact. In preformed biofilms, viable cell counts were reduced by 4 logs at therapeutic concentrations. Complexation of iron and zinc was demonstrated to underlie nitroxoline's potent antibiofilm activity.

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