Search results for "Microbial interaction"

Influence of cell-cell contact between L. thermotolerans and S. cerevisiae on yeast interactions and the exo-metabolome

2019

International audience; Sequential fermentation of grape must inoculated with L. thermotolerans and then S. cerevisiae 24 h later (typical wine-making practice) was conducted with or without cell-cell contact between the two yeast species. We monitored cell viability of the two species throughout fermentation by flow cytometry. The cell viability of S. cerevisiae decreased under both conditions, but the decrease was greater if there was cell-cell contact. An investigation of the nature of the interactions showed competition between the two species for nitrogen compounds, oxygen, and must sterols. Volatile-compound analysis showed differences between sequential and pure fermentation and that…

Selective growth-inhibitory effect of 8-hydroxyquinoline towards Clostridium difficile and Bifidobacterium longum subsp. longum in co-culture analyse…

2014

The major risk factor for Clostridium difficile infection (CDI) is the use of antibiotics owing to the disruption of the equilibrium of the host gut microbiota. To preserve the beneficial resident probiotic bacteria during infection treatment, the use of molecules with selective antibacterial activity enhances the efficacy by selectively removing C. difficile. One of them is the plant alkaloid 8-hydroxyquinoline (8HQ), which has been shown to selectively inhibit clostridia without repressing bifidobacteria. Selective antimicrobial activity is generally tested by culture techniques of individual bacterial strains. However, the main limitation of these techniques is the inability to describe …

Opportunities and Challenges to Microbial Symbiosis Research in the Microbiome Era

2020

Peer reviewed

Experimental community coalescence sheds light on microbial interactions in soil and restores impaired functions

2023

Abstract Background Microbes typically live in communities where individuals can interact with each other in numerous ways. However, knowledge on the importance of these interactions is limited and derives mainly from studies using a limited number of species grown in coculture. Here, we manipulated soil microbial communities to assess the contribution of interactions between microorganisms for assembly of the soil microbiome. Results By combining experimental removal (taxa depletion in the community) and coalescence (mixing of manipulated and control communities) approaches, we demonstrated that interactions between microorganisms can play a key role in determining their fitness during soi…

Antibiotic susceptibility of cocultures in polymicrobial infections such as peri-implantitis or periodontitis: an in vitro model.

2011

Although polymicrobial infections, such as peri-implantitis or periodontitis, were postulated in the literature to be caused by synergistic effects of bacteria, these effects remain unclear looking at antibiotic susceptibility. The aim of this study is to compare the antibiotic susceptibilities of pure cultures and definite cocultures.Laboratory strains of Aggregatibacter actinomycetemcomitans (Aa) (previously Actinobacillus actinomycetemcomitans), Capnocytophaga ochracea (Co), and Parvimonas micra (Pm) (previously Peptostreptococcus micros) were cultivated under anaerobic conditions, and their susceptibilities to 10 antibiotics (benzylpenicillin G, ampicillin, amoxicillin, ampicillin/sulba…

The Microbiota: A Microbial Ecosystem Built on Mutualism Prevails

2019

The role of gut micorbiome in obesity and diabetes

2019

Background Obesity and diabetes became a grooving problem in both adults and children. Many hypotheses concerned agents involved in the excessive weight gain process and it’s consequences. Not only genetic or environmental factors, but also intestinal microbiome seems to play a role in the pathophysiology of this phenomenon. Data sources A systematic review was conducted using Pubmed as the medical database source. Studies concerning connection between microbiome and metabolic disorders such as obesity and diabetes from last 10 years were analyzed. Results Intestinal bacteria may be involved both in the development of obesity, and its further complications. The pro-infammatory and immunomod…

Human norovirus binding to select bacteria representative of the human gut microbiota

2016

Recent reports describe the ability of select bacterial strains to bind human norovirus, although the specificity of such interactions is unknown. The purpose of this work was to determine if a select group of bacterial species representative of human gut microbiota bind to human norovirus, and if so, to characterize the intensity and location of that binding. The bacteria screened included naturally occurring strains isolated from human stool (Klebsiella spp., Citrobacter spp., Bacillus spp., Enterococcus faecium and Hafnia alvei) and select reference strains (Staphylococcus aureus and Enterobacter cloacae). Binding in PBS was evaluated to three human norovirus strains (GII.4 New Orleans 2…

A metabolomic study of yeast/bacteria interactions

2015

As a complex microbial ecosystem, wine is a particularly interesting model for studying interactions between microorganisms. Contact-independent interactions (indirect interactions) between the yeast Saccharomyces cerevisae and the lactic acid bacterium Oenococcus oeni have a direct effect on malolactic fermentation (MLF), induction and completion, which is an important factor in wine quality. Yeast strains could be classified as MLF+ phenotype if it usually stimulates the bacterial growth or MLF- in the opposite case. The known metabolites that stimulate or inhibit the MLF cannot always explain the phenotypic distinction. In this work, a multidisciplinary workflow combining non-targeted me…

Exploring the diversity of listeria monocytogenes biofilm architecture by high-throughput confocal laser scanning microscopy and the predominance of …

2015

ABSTRACT Listeria monocytogenes is involved in food-borne illness with a high mortality rate. The persistence of the pathogen along the food chain can be associated with its ability to form biofilms on inert surfaces. While most of the phenotypes associated with biofilms are related to their spatial organization, most published data comparing biofilm formation by L. monocytogenes isolates are based on the quantitative crystal violet assay, which does not give access to structural information. Using a high-throughput confocal-imaging approach, the aim of this work was to decipher the structural diversity of biofilms formed by 96 L. monocytogenes strains isolated from various environments. Pr…