Exudation from 14C-labeled fungal propagules in the presence of specific microorganisms

1983 ◽  
Vol 29 (11) ◽  
pp. 1487-1492 ◽  
Author(s):  
D. K. Arora ◽  
A. B. Filonow ◽  
J. L. Lockwood
Keyword(s):  
Phosphate Buffer ◽  
Bacterial Species ◽  
Macrophomina Phaseolina ◽  
Fungal Species ◽  
Bacterial Cells ◽  
Labeled Compounds ◽  
Population Densities ◽  
Cochliobolus Victoriae ◽  
Fungal Propagules

Exudation from 14C-labeled conidia of Cochliobolus victoriae and sclerotia of Macrophomina phaseolina was greater in the presence of cells of five bacterial species or propagules of four fungal species in phosphate buffer or in sterilized soil than in buffer without other microorganisms. In most instances, the increased exudation was statistically significant at P = 0.05. High population densities of bacterial cells or fungal propagules induced greater exudation than lower densities. 14C exudation from C. victoriae conidia in the presence of specific microorganisms was 1.5–9.9% of total label in buffer and 1.0–3.8% on soil; exudation from M. phaseolina sclerotia was 1.4–3.2% of total label in buffer and 1.3–3.2% on soil. All microorganisms tested, except Actinoplanes utahensis and M. phaseolina, suppressed germination of conidia of C. victoriae and sclerotia of M. phaseolina in vitro. Exudation of 14C-labeled compounds was inversely correlated with germination of C. victoriae conidia (r = −0.72) and M. phaseolina sclerotia (r = −0.74). The results indicate that specific microorganisms can enhance exudation from fungal propagules and that the enhanced exudation may be related to the imposition of mycostasis.

Bacterial chemotaxis to fungal propagules in vitro and in soil

1983 ◽  
Vol 29 (9) ◽  
pp. 1104-1109 ◽  
Author(s):  
D. K. Arora ◽  
A. B. Filonow ◽  
J. L. Lockwood
Keyword(s):  
Sandy Loam ◽  
Phosphate Buffer Solution ◽  
Bacterial Chemotaxis ◽  
Macrophomina Phaseolina ◽  
Buffer Solution ◽  
Erwinia Herbicola ◽  
Cochliobolus Victoriae ◽  
Fungal Propagules ◽  
Loam Soil

Erwinia herbicola, Pseudomonas fluorescens, and P. putida were strongly attracted in vitro to substances exuded by conidia of Cochliobolus victoriae and sclerotia of Macrophomina phaseolina, but not to phosphate buffer solution. Numbers of bacteria attracted to propagules of C. victoriae or M. phaseolina in an unsterilized sandy loam soil were significantly (P = 0.05) greater than background populations occurring in soil saturated with buffer. Chemotactic response was greater to C. victoriae than to M. phaseolina both in vitro and in soil. Results suggest that living fungal propagules may act as attractants for motile bacteria in soil.

scholarly journals A New Front in Microbial Warfare—Delivery of Antifungal Effectors by the Type VI Secretion System

2019 ◽  
Vol 5 (2) ◽  
pp. 50 ◽  
Author(s):  
Katharina Trunk ◽  
Sarah J. Coulthurst ◽  
Janet Quinn
Keyword(s):  
Bacterial Species ◽  
Fungal Species ◽  
Secretion System ◽  
Effector Proteins ◽  
Primary Role ◽  
Bacterial Cells ◽  
Type Vi Secretion System ◽  
Type Vi Secretion ◽  
Bacteria And Fungi ◽  
Polymicrobial Communities

Microbes typically exist in mixed communities and display complex synergistic and antagonistic interactions. The Type VI secretion system (T6SS) is widespread in Gram-negative bacteria and represents a contractile nano-machine that can fire effector proteins directly into neighbouring cells. The primary role assigned to the T6SS is to function as a potent weapon during inter-bacterial competition, delivering antibacterial effectors into rival bacterial cells. However, it has recently emerged that the T6SS can also be used as a powerful weapon against fungal competitors, and the first fungal-specific T6SS effector proteins, Tfe1 and Tfe2, have been identified. These effectors act via distinct mechanisms against a variety of fungal species to cause cell death. Tfe1 intoxication triggers plasma membrane depolarisation, whilst Tfe2 disrupts nutrient uptake and induces autophagy. Based on the frequent coexistence of bacteria and fungi in microbial communities, we propose that T6SS-dependent antifungal activity is likely to be widespread and elicited by a suite of antifungal effectors. Supporting this hypothesis, homologues of Tfe1 and Tfe2 are found in other bacterial species, and a number of T6SS-elaborating species have been demonstrated to interact with fungi. Thus, we envisage that antifungal T6SS will shape many polymicrobial communities, including the human microbiota and disease-causing infections.

scholarly journals Natural Transformation of Acinetobactersp. Strain BD413 with Cell Lysates of Acinetobacter sp.,Pseudomonas fluorescens, and Burkholderia cepaciain Soil Microcosms

2000 ◽  
Vol 66 (1) ◽  
pp. 206-212 ◽  
Author(s):  
Kaare M. Nielsen ◽  
Kornelia Smalla ◽  
Jan D. van Elsas
Keyword(s):  
Pseudomonas Fluorescens ◽  
Burkholderia Cepacia ◽  
Natural Transformation ◽  
Bacterial Species ◽  
Physical Stability ◽  
Biological Significance ◽  
Bacterial Cells ◽  
Chromosomal Dna ◽  
Cell Lysates

ABSTRACT To elucidate the biological significance of dead bacterial cells in soil to the intra- and interspecies transfer of gene fragments by natural transformation, we have exposed the kanamycin-sensitive recipient Acinetobacter sp. strain BD413(pFG4) to lysates of the kanamycin-resistant donor bacteria Acinetobacterspp., Pseudomonas fluorescens, and Burkholderia cepacia. Detection of gene transfer was facilitated by the recombinational repair of a partially (317 bp) deleted kanamycin resistance gene in the recipient bacterium. The investigation revealed a significant potential of these DNA sources to transformAcinetobacter spp. residing both in sterile and in nonsterile silt loam soil. Heat-treated (80°C, 15 min) cell lysates were capable of transforming strain BD413 after 4 days of incubation in sterile soil and for up to 8 h in nonsterile soil. Transformation efficiencies obtained in vitro and in situ with the various lysates were similar to or exceeded those obtained with conventionally purified DNA. The presence of cell debris did not inhibit transformation in soil, and the debris may protect DNA from rapid biological inactivation. Natural transformation thus providesAcinetobacter spp. with an efficient mechanism to access genetic information from different bacterial species in soil. The relatively short-term biological activity (e.g., transforming activity) of chromosomal DNA in soil contrasts the earlier reported long-term physical stability of DNA, where fractions have been found to persist for several weeks in soil. Thus, there seems to be a clear difference between the physical and the functional significance of chromosomal DNA in soil.

scholarly journals Comparison of Japanese and Indian intestinal microbiota shows diet-dependent interaction between bacteria and fungi

2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Siddhika Pareek ◽  
Takashi Kurakawa ◽  
Bhabatosh Das ◽  
Daisuke Motooka ◽  
Shuuichi Nakaya ◽  
...  
Keyword(s):  
Bacterial Species ◽  
Fungal Species ◽  
Growth Responses ◽  
Potential Growth ◽  
Plant Polysaccharides ◽  
Plant Polysaccharide ◽  
Mouse Intestine ◽  
Bacteria And Fungi ◽  
Culture Supernatants

AbstractThe bacterial species living in the gut mediate many aspects of biological processes such as nutrition and activation of adaptive immunity. In addition, commensal fungi residing in the intestine also influence host health. Although the interaction of bacterium and fungus has been shown, its precise mechanism during colonization of the human intestine remains largely unknown. Here, we show interaction between bacterial and fungal species for utilization of dietary components driving their efficient growth in the intestine. Next generation sequencing of fecal samples from Japanese and Indian adults revealed differential patterns of bacterial and fungal composition. In particular, Indians, who consume more plant polysaccharides than Japanese, harbored increased numbers of Prevotella and Candida. Candida spp. showed strong growth responses to the plant polysaccharide arabinoxylan in vitro. Furthermore, the culture supernatants of Candida spp. grown with arabinoxylan promoted rapid proliferation of Prevotella copri. Arabinose was identified as a potential growth-inducing factor in the Candida culture supernatants. Candida spp. exhibited a growth response to xylose, but not to arabinose, whereas P. copri proliferated in response to both xylose and arabinose. Candida spp., but not P. copri, colonized the intestine of germ-free mice. However, P. copri successfully colonized mouse intestine already harboring Candida. These findings demonstrate a proof of concept that fungal members of gut microbiota can facilitate a colonization of the intestine by their bacterial counterparts, potentially mediated by a dietary metabolite.

scholarly journals Impact of air pollution on buff-tailed bumblebees (Bombus terrestris) and their gut microbiome

2020 ◽  
Vol 2 (7A) ◽  
Author(s):  
Hannah Sampson ◽  
Julian Ketley ◽  
Eamonn Mallon ◽  
Julie Morrissey
Keyword(s):  
Air Pollution ◽  
Gut Microbiome ◽  
Bombus Terrestris ◽  
Bacterial Species ◽  
Published Data ◽  
Bacterial Cells ◽  
Microbiome Composition ◽  
Bee Health

Bumblebees play a major role in global pollination. Consequently, their health is of high importance for food security worldwide. Yet, recent population estimates show that their numbers are declining. This decline has been attributed to habitat loss, infection and use of pesticides. An important factor for bee health that contributes to population survival is the gut microbiome composition. The bee gut microbiome provides protection from pathogens, is specific to the host and helps break down food. Without a balanced gut microbiome, the health of the bee is threatened through increased infection and mortality. The bee gut microbiome is relatively simple, being dominated by 8 core bacterial species providing a convenient study system. Previous published data shows that air pollution has an impact on bacterial behaviour. Therefore, our hypothesis is exposure to air pollution causes an imbalance in the bee gut microbiome. To test this, we exposed bees to black carbon (BC), a major component of air pollution particulate matter. We assessed the effects on bee behaviour, microbiome composition and gut bacteria treated in vitro. Bees treated with BC showed a significant increase in viable bacterial cells in their faecal community. Independent culture of gut commensals showed that BC significantly alters the structure of their biofilms, which are important for colonisation in vivo. This supports the hypothesis that air pollution can cause an imbalance in the bee gut microbiome, and may adversely influence bee health and pollinator populations.

scholarly journals Antimicrobial screening of selected flora of Pakistan

2011 ◽  
Vol 63 (3) ◽  
pp. 691-695 ◽  
Author(s):  
M. Zia-Ul-Haq ◽  
Mansoor Ahmad ◽  
M Mehjabeen ◽  
Noor Jehan ◽  
Shakeel Ahmad ◽  
...  
Keyword(s):  
Nigella Sativa ◽  
Micrococcus Luteus ◽  
Bacterial Species ◽  
Macrophomina Phaseolina ◽  
Salmonella Typhi ◽  
Lepidium Sativum ◽  
Significant Activity ◽  
Fungal Strains ◽  
Antibacterial And Antifungal Activities

Ethanolic extracts of Ferula assafoetida resin, Grewia asiatica leaves, Ipomoea hederacea seeds, Lepidium sativum seeds, Nigella sativa seeds and Terminalia chebula fruits were tested in vitro for their antibacterial and antifungal activities. The antibacterial study performed against eight bacterial species viz., Escherichia coli, Citrobacter, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella typhi, Micrococcus luteus, Proteus mirabilis and Bacillus subtilis indicated that the investigated plants have potent activity against all the tested microorganisms. The antifungal activity of these extracts was performed against nine fungal strains, viz., Aspergillus parasiticus, Aspergillus niger, Yersinia aldovae, Candida albicans, Aspergillus effusus, Fusarium solani, Macrophomina phaseolina, Saccharomyces cerevisiae and Trichophyton rubrum. The extracts showed moderate as well as significant activity against the different fungal strains.

scholarly journals Contributions ofCandida albicansDimorphism, Adhesive Interactions, and Extracellular Matrix to the Formation of Dual-Species Biofilms withStreptococcus gordonii

mBio ◽  
2019 ◽  
Vol 10 (3) ◽  
Author(s):  
Daniel Montelongo-Jauregui ◽  
Stephen P. Saville ◽  
Jose L. Lopez-Ribot
Keyword(s):  
Extracellular Matrix ◽  
Oral Cavity ◽  
Bacterial Species ◽  
Fungal Species ◽  
Bacterial Cells ◽  
Mixed Species ◽  
Bacterial Populations ◽  
Content Type ◽  
Mutant Strains ◽  
Adhesive Interactions

ABSTRACTFungal and bacterial populations coexist in the oral cavity, frequently forming mixed-species biofilms that complicate treatment against polymicrobial infections. However, despite relevance to oral health, the bidirectional interactions between these microbial populations are poorly understood. In this study, we aimed to elucidate the mechanisms underlying the interactions between the fungal speciesCandida albicansand the bacterial speciesStreptococcus gordoniias they coexist in mixed-species biofilms. Specifically, the interactions of differentC. albicansmutant strains deficient in filamentation (efg1Δ/Δ andbrg1Δ/Δ), adhesive interactions (als3Δ/Δ andbcr1Δ/Δ), and production of matrix exopolymeric substances (EPS) (kre5Δ/Δ, mnn9Δ/Δ,rlm1Δ/Δ, andzap1Δ/Δ) were evaluated withS. gordoniiunder different conditions mimicking the environment in the oral cavity. Interestingly, our results revealed that growth of the biofilm-deficientC. albicansals3Δ/Δandbcr1Δ/Δmutant strains in synthetic saliva or withS. gordoniirestored their biofilm-forming ability. Moreover, challenging previous observations indicating an important role of morphogenetic conversions in the interactions between these two species, our results indicated a highly synergistic interaction betweenS. gordoniiand theC. albicansfilamentation-deficientefg1Δ/Δandbrg1Δ/Δdeletion mutants, which was particularly noticeable when the mixed biofilms were grown in synthetic saliva. Importantly, dual-species biofilms were found to exhibit increase in antimicrobial resistance, indicating that components of the fungal exopolymeric material confer protection to streptococcal cells against antibacterial treatment. Collectively, these findings unravel a high degree of complexity in the interactions betweenC. albicansandS. gordoniiin mixed-species biofilms, which may impact homeostasis in the oral cavity.IMPORTANCEMicrobial communities have a great impact in health and disease.C. albicansinteracts with multiple microorganisms in the oral cavity, frequently forming polymicrobial biofilms. We report on the synergistic interactions betweenC. albicansand the Gram-positive bacteriumS. gordonii, for which we have examined the different contributions of adhesive interactions, filamentation, and the extracellular matrix to the formation of dual-species biofilms. Our results demonstrate that growth in the presence of the bacterium can restore the biofilm-forming ability of differentC. albicansmutant strains with defects in adhesion and filamentation. The mixed-species biofilms also show high levels of resistance to antibacterial and antifungal antibiotics, and our results indicate that the fungal biofilm matrix protects bacterial cells within these mixed-species biofilms. Our observations add to a growing body of evidence indicating a high level of complexity in the reciprocal interactions and consortial behavior of fungal/bacterial biofilms.

scholarly journals RNA Polymerases from Bacillus subtilisand Escherichia coli Differ in Recognition of Regulatory Signals In Vitro

2000 ◽  
Vol 182 (21) ◽  
pp. 6027-6035 ◽  
Author(s):  
Irina Artsimovitch ◽  
Vladimir Svetlov ◽  
Larry Anthony ◽  
Richard R. Burgess ◽  
Robert Landick
Keyword(s):  
Escherichia Coli ◽  
Bacterial Species ◽  
In Vitro Transcription ◽  
Rna Polymerases ◽  
Bacterial Cells ◽  
Signal Recognition ◽  
E Coli ◽  
Promoter Recognition ◽  
Species Specific

ABSTRACT Adaptation of bacterial cells to diverse habitats relies on the ability of RNA polymerase to respond to various regulatory signals. Some of these signals are conserved throughout evolution, whereas others are species specific. In this study we present a comprehensive comparative analysis of RNA polymerases from two distantly related bacterial species, Escherichia coli and Bacillus subtilis, using a panel of in vitro transcription assays. We found substantial species-specific differences in the ability of these enzymes to escape from the promoter and to recognize certain types of elongation signals. Both enzymes responded similarly to other pause and termination signals and to the general E. coli elongation factors NusA and GreA. We also demonstrate that, although promoter recognition depends largely on the ς subunit, promoter discrimination exhibited in species-specific fashion by both RNA polymerases resides in the core enzyme. We hypothesize that differences in signal recognition are due to the changes in contacts made between the β and β′ subunits and the downstream DNA duplex.

Chemotaxis of some phytopathogenic bacteria to fungal propagules in vitro and in soil

1988 ◽  
Vol 34 (2) ◽  
pp. 196-199 ◽  
Author(s):  
W. C. Lim ◽  
J. L. Lockwood
Keyword(s):  
Pseudomonas Syringae ◽  
Xanthomonas Campestris ◽  
Pathogenic Bacteria ◽  
Erwinia Carotovora ◽  
Bipolaris Sorokiniana ◽  
Macrophomina Phaseolina ◽  
Plant Pathogenic Bacteria ◽  
Fungal Propagules ◽  
Xanthomonas Campestris Pv Campestris

The motile plant pathogenic bacteria Erwinia carotovora pv. carotovora, Pseudomonas syringae pv. phaseolicola, and Xanthomonas campestris pv. campestris were strongly attracted to conidia of Bipolaris sorokiniana, B. victoriae, and to sclerotia of Macrophomina phaseolina and their exudates in vitro and in soil, but not to phosphate buffer or buffer–soil mixtures. Bacteria accumulated radioactivity within 1 h after being placed in exudates from 14C-labelled conidia of B. sorokiniana. After 5 h, radioactivity of the 14C-labelled exudate was reduced to 29–54% of that in the original medium. Exudates from fungal propagules may act as attractants and substrates for motile plant pathogenic bacteria in soil.

scholarly journals Determination of Biocontrol Potential of Bacillus spp. and Stenotrophomonas sp. against Macrophomina phaseolina in Sunflower

2022 ◽  
Vol 9 (sp) ◽  
pp. 2480-2485
Author(s):  
Özden Salman ◽  
Raziye Koçak ◽  
Nuh Boyraz
Keyword(s):  
Bacterial Species ◽  
Inhibition Zone ◽  
Macrophomina Phaseolina ◽  
Bacterial Strains ◽  
Environment And Health ◽  
Soil Pathogen ◽  
Bacillus Spp ◽  
Biocontrol Potential

Macrophomina phaseolina is a soil pathogen known as charcoal rot and can cause up to 90% yield loss in sunflower under suitable conditions. The serious damage caused by chemicals used in the control of soil-borne pathogens to the environment and health has become one of the most important concerns in agriculture. Therefore, in our study, it was aimed to determine the in vitro antagonistic effects of various bacterial species against M phaseolina. A total of 38 bacterial strains were isolated from soil samples in the rhizosphere of Malva sylvestris (hibiscus), Vicia sativa (vetch), Cicer arietinum (chickpea), Papaver rhoeas (weasel), Carlina marianum (thistle), Glebionis coronaria (crown daisy) and Vicia faba collected from Urla district of İzmir. All bacterial strains exhibited antibiosis effect under in vitro conditions, but it was determined that 5 bacterial isolates among them showed a high inhibition zone and showed an average inhibition potential ranging between 55% and 74%. The most effective bacteria identified at species and genus level by Maldi biotyping (MALDI-TOF MS) were identified as Bacillus amyloliquefaciens, Stenotrophomonas sp. and Bacillus cereus (3 isolates), and these species showed that they can be important biocontrol agents in biological control against M. phaseolina.

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