scholarly journals An accelerated method for determining «self/non-self» microorganisms in the agglutination reaction

2020 ◽  
Vol 10 (4) ◽  
pp. 792-796
Author(s):  
O. V. Bukharin ◽  
N. B. Perunova ◽  
I. N. Chainikova ◽  
E. V. Ivanova ◽  
S. V. Andryushchenko
Keyword(s):  
Escherichia Coli ◽  
Cell Cultures ◽  
Shigella Flexneri ◽  
Bifidobacterium Longum ◽  
Bifidobacterium Bifidum ◽  
Ease Of Use ◽  
Agglutination Reaction ◽  
Bacterial Strains ◽  
Recognition Method ◽  
Self Recognition

A simple accelerated method for determining «self/non-self» microorganisms by using the agglutination reaction (RA) and therapeutic/prophylactic serum (Immunoglobulin complex preparation, lyophilized IgG, IgA, IgM immunoglobulins, developed by CSC Immuno-Gem, Moscow) is proposed to test for pathogenic, opportunistic and dominant probiotic Bifidobacteria spp. In parallel, all the microbial cell cultures examined were registered in the databases of Russia-wide and international collections and tested by the intermicrobial “self/non-self” recognition method, previously developed by us. 16 collection strains of various microorganisms were assessed by the RA with relevant therapeutic and prophylactic serum. Biological samples were obtained from the collection bacterial strains of Bifidobacterium bifidum 791, Escherichia coli LEGM-18, Klebsiella pneumoniae 278, Lactobacillus fermentum 90T-C4, Bifidobacterium longum MC-42, Escherichia coli M-17, Shigella sonnei 177b, Shigella flexneri 170, Escherichia coli 157, Staphylococcus aureus 209, Candida albicans 10231 and Salmonella serovar Enteritidis ATCC 10708. In addition, cell cultures obtained from the Museum of the Institute of Cellular and Intracellular Symbiosis UB RAS such as Bifidobacterium longum ICIS-505, Lactobacillus acidophilus ICIS-1127, Bifidobacterium bifidum ICIS-202, Bifidobacterium bifidum ICIS-310 were also included into the study. To assess microbial peptidoglycan foreignness, the intermicrobial “self/non-self” recognition method was also used based on inducing metabolites produced by the “dominant” test strain Bifidobacterium longum MC-42 after pre-incubation with metabolites collected from the studied cell cultures (“associates”) followed by established “dominant-associate” feedback loop. The data were evaluated by assessing change-fold in reproduction (growth/replication) and adaptation (biofilm formation and anti-lysozyme test) of microbial cultures in accordance with the described technique followed by comparing these two methods for intermicrobial “self/non-self” recognition. All the RA data were found to fully agree with those obtained after previous studies by using intermicrobial “self/non-self” recognition method coupled to “dominant-associate” system. Moreover, compared to analogous “intermicrobial recognition” method (5 days), ease of use and test timeframe (24 hours) allow to consider RA attractive for screening studies to select strains for scientific and industrial purposes.

scholarly journals Genome Features and In Vitro Activity against Influenza A and SARS-CoV-2 Viruses of Six Probiotic Strains

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Irina V. Soloveva ◽  
Tatyana N. Ilyicheva ◽  
Vasiliy Yu. Marchenko ◽  
Oleg V. Pyankov ◽  
Anna G. Tochilina ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Influenza A ◽  
Mdck Cells ◽  
Bifidobacterium Longum ◽  
Bifidobacterium Bifidum ◽  
Influenza Viruses ◽  
Lactobacillus Fermentum ◽  
Probiotic Bacteria ◽  
Bacterial Strains

Purpose. The aim of this work was to analyze the complete genome of probiotic bacteria Lactobacillus plantarum 8 RA 3, Lactobacillus fermentum 90 TC-4, Lactobacillus fermentum 39, Bifidobacterium bifidum 791, Bifidobacterium bifidum 1, and Bifidobacterium longum 379 and to test their activity against influenza A and SARS-CoV-2 viruses. Methods. To confirm the taxonomic affiliation of the bacterial strains, MALDI TOF mass spectrometry and biochemical test systems were used. Whole genome sequencing was performed on the Illumina Inc. MiSeq platform. To determine the antiviral activity, A/Lipetsk/1V/2018 (H1N1 pdm09) (EPI_ISL_332798) and A/common gull/Saratov/1676/2018 (H5N6) (EPI_ISL_336925) influenza viruses and SARS-CoV-2 virus strain Australia/VIC01/2020 (GenBank: MT007544.1) were used. Results. All studied probiotic bacteria are nonpathogenic for humans and do not contain the determinants of transmission-type antibiotic resistance and integrated plasmids. Resistance to antibiotics of different classes is explained by the presence of molecular efflux pumps of the MatE and MFS families. Cultures of L. fermentum 90 TC 4, L. plantarum 8 RA 3, and B. bifidum 791 showed a pronounced activity against influenza A viruses in MDCK cells. Activity against the SARS-CoV-2 virus was demonstrated only by the L. fermentum 90 TC 4 strain in VERO cells. Conclusions. The studied probiotic bacteria are safe, have antiviral activity, and are of great importance for the prevention of diseases caused by respiratory viruses that can also infect the human intestine.

scholarly journals Unraveling the Leloir Pathway of Bifidobacterium bifidum: Significance of the Uridylyltransferases

2013 ◽  
Vol 79 (22) ◽  
pp. 7028-7035 ◽  
Author(s):  
Frederik De Bruyn ◽  
Joeri Beauprez ◽  
Jo Maertens ◽  
Wim Soetaert ◽  
Marjan De Mey
Keyword(s):  
Escherichia Coli ◽  
Human Milk ◽  
Bifidobacterium Longum ◽  
Bifidobacterium Bifidum ◽  
Human Milk Oligosaccharides ◽  
Content Type ◽  
Leloir Pathway ◽  
Functional Analog ◽  
Major Route ◽  
Galactose Utilization

ABSTRACTThe GNB/LNB (galacto-N-biose/lacto-N-biose) pathway plays a crucial role in bifidobacteria during growth on human milk or mucin from epithelial cells. It is thought to be the major route for galactose utilization inBifidobacterium longumas it is an energy-saving variant of the Leloir pathway. Both pathways are present inB. bifidum, and galactose 1-phosphate (gal1P) is considered to play a key role. Due to its toxic nature, gal1P is further converted into its activated UDP-sugar through the action of poorly characterized uridylyltransferases. In this study, three uridylyltransferases (galT1,galT2, andugpA) fromBifidobacterium bifidumwere cloned in anEscherichia colimutant and screened for activity on the key intermediate gal1P. GalT1 and GalT2 showed UDP-glucose-hexose-1-phosphate uridylyltransferase activity (EC 2.7.7.12), whereas UgpA showed promiscuous UTP-hexose-1-phosphate uridylyltransferase activity (EC 2.7.7.10). The activity of UgpA toward glucose 1-phosphate was about 33-fold higher than that toward gal1P. GalT1, as part of the bifidobacterial Leloir pathway, was about 357-fold more active than GalT2, the functional analog in the GNB/LNB pathway. These results suggest that GalT1 plays a more significant role than previously thought and predominates whenB. bifidumgrows on lactose and human milk oligosaccharides. GalT2 activity is required only during growth on substrates with a GNB core such as mucin glycans.

Effet d'une souche de Lactobacillus sur la cinétique d'établissement de Shigella flexneri et d'Escherichia coli dans le tube digestif de souriceaux "Gnotoxéniques." Rôle de l'immunisation des mères

1973 ◽  
Vol 19 (8) ◽  
pp. 1021-1030 ◽  
Author(s):  
R. Ducluzeau ◽  
P. Raibaud
Keyword(s):  
Escherichia Coli ◽  
Shigella Flexneri ◽  
Maximum Level ◽  
Antagonistic Effect ◽  
Tube Digestif ◽  
Bacterial Strains ◽  
E Coli ◽  
Small Measure ◽  
Pregnant Mothers ◽  
Young Mice

A strain of either Shigella flexneri, Escherichia coli, or each of these two strains with a strain of Lactobacillus is implanted in the digestive tract of different couples of axenic adult mice.Some pregnant mothers are vaccinated with the three strains before implantation. The vaccination does not change the kinetics establishment of all three bacterial strains in either the mothers or the young.Escherichia coli is established at its maximum level in "monoxenic" young mice at day 3 after birth, while Shigella appears slowly and irregularly during the 1st week of life. Both strains are established almost simultaneously in the stomach and intestine of the young mice.Lactobacillus is established at maximum level in the stomach and intestine of "dixenic" young mice at day 1 after birth. In these conditions, Shigella appears slowly, only reaching maximum level at 17 days. This antagonistic effect is especially observed in the stomach of the animals, and in a small measure, in the intestine. The establishment of E. coli is hardly affected by the presence of Lactobacillus, except in the stomach in most young animals.In no case is there interference between Lactobacillus and either one of the two strains after 3 weeks of age.

Galacto- and Fructo-oligosaccharides Utilized for Growth by Cocultures of Bifidobacterial Species Characteristic of the Infant Gut

2020 ◽  
Author(s):  
Ian Sims ◽  
GW Tannock
Keyword(s):  
Breast Milk ◽  
Bacterial Species ◽  
Bifidobacterium Longum ◽  
Well Being ◽  
Bifidobacterium Bifidum ◽  
Child Rearing ◽  
Potential Growth ◽  
Human Infants ◽  
Infant Diet ◽  
Growth Substrates

Copyright © 2020 American Society for Microbiology. Bifidobacterial species are common inhabitants of the gut of human infants during the period when milk is a major component of the diet. Bifidobacterium breve, Bifidobacterium bifidum, Bifidobacterium longum subspecies longum, and B. longum subspecies infantis have been detected frequently in infant feces, but B. longum subsp. infantis may be disadvantaged numerically in the gut of infants in westernized countries. This may be due to the different durations of breast milk feeding in different countries. Supplementation of the infant diet or replacement of breast milk using formula feeds is common in Western countries. Formula milks often contain galacto- and/or fructo-oligosaccharides (GOS and FOS, respectively) as additives to augment the concentration of oligosaccharides in ruminant milks, but the ability of B. longum subsp. infantis to utilize these potential growth substrates when they are in competition with other bifidobacterial species is unknown. We compared the growth and oligosaccharide utilization of GOS and FOS by bifidobacterial species in pure culture and coculture. Short-chain GOS and FOS (degrees of polymerization [DP] 2 and 3) were favored growth substrates for strains of B. bifidum and B. longum subsp. longum, whereas both B. breve and B. longum subsp. infantis had the ability to utilize both short- and longer-chain GOS and FOS (DP 2 to 6). B. breve was nevertheless numerically dominant over B. longum subsp. infantis in cocultures. This was probably related to the slower use of GOS of DP 3 by B. longum subsp. infantis, indicating that the kinetics of substrate utilization is an important ecological factor in the assemblage of gut communities.IMPORTANCE The kinds of bacteria that form the collection of microbes (the microbiota) in the gut of human infants may influence health and well-being. Knowledge of how the composition of the infant diet influences the assemblage of the bacterial collection is therefore important because dietary interventions may offer opportunities to alter the microbiota with the aim of improving health. Bifidobacterium longum subspecies infantis is a well-known bacterial species, but under modern child-rearing conditions it may be disadvantaged in the gut. Modern formula milks often contain particular oligosaccharide additives that are generally considered to support bifidobacterial growth. However, studies of the ability of various bifidobacterial species to grow together in the presence of these oligosaccharides have not been conducted. These kinds of studies are essential for developing concepts of microbial ecology related to the influence of human nutrition on the development of the gut microbiota.

scholarly journals Structure of the master regulator Rns reveals an inhibitor of enterotoxigenic Escherichia coli virulence regulons

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Charles R. Midgett ◽  
Kacey Marie Talbot ◽  
Jessica L. Day ◽  
George P. Munson ◽  
F. Jon Kull
Keyword(s):  
Escherichia Coli ◽  
Small Molecules ◽  
Family Member ◽  
Shigella Flexneri ◽  
Decanoic Acid ◽  
Enterotoxigenic Escherichia Coli ◽  
Gram Negative Bacteria ◽  
Enteric Infections ◽  
First Time ◽  
Arac Family

AbstractEnteric infections caused by the gram-negative bacteria enterotoxigenic Escherichia coli (ETEC), Vibrio cholerae, Shigella flexneri, and Salmonella enterica are among the most common and affect billions of people each year. These bacteria control expression of virulence factors using a network of transcriptional regulators, some of which are modulated by small molecules as has been shown for ToxT, an AraC family member from V. cholerae. In ETEC the expression of many types of adhesive pili is dependent upon the AraC family member Rns. We present here the 3 Å crystal structure of Rns and show it closely resembles ToxT. Rns crystallized as a dimer via an interface similar to that observed in other dimeric AraC’s. Furthermore, the structure of Rns revealed the presence of a ligand, decanoic acid, that inhibits its activity in a manner similar to the fatty acid mediated inhibition observed for ToxT and the S. enterica homologue HilD. Together, these results support our hypothesis that fatty acids regulate virulence controlling AraC family members in a common manner across a number of enteric pathogens. Furthermore, for the first time this work identifies a small molecule capable of inhibiting the ETEC Rns regulon, providing a basis for development of therapeutics against this deadly human pathogen.

scholarly journals Influence of Bacterial Competitors on Salmonella enterica and Enterohemorrhagic Escherichia coli Growth in Microbiological Media and Attachment to Vegetable Seeds

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 285
Author(s):  
Da Liu ◽  
Ronald Walcott ◽  
Kevin Mis Solval ◽  
Jinru Chen
Keyword(s):  
Escherichia Coli ◽  
Foodborne Pathogens ◽  
Salmonella Enterica ◽  
Lactobacillus Rhamnosus ◽  
Probiotic Bacterium ◽  
Enterohemorrhagic Escherichia Coli ◽  
Biocontrol Agents ◽  
Human Pathogens ◽  
Bacterial Strains ◽  
Pathogen Populations

Interests in using biological agents for control of human pathogens on vegetable seeds are rising. This study evaluated whether probiotic bacterium Lactobacillus rhamnosus GG, bacterial strains previously used as biocontrol agents in plant science, as well as a selected plant pathogen could compete with foodborne human pathogens, such as Salmonella enterica and enterohemorrhagic Escherichia coli (EHEC), for growth in microbiological media and attachment to vegetable seeds; and to determine whether the metabolites in cell-free supernatants of competitive bacterial spent cultures could inhibit the growth of the two pathogens. The results suggest that the co-presence of competitive bacteria, especially L. rhamnosus GG, significantly (p < 0.05) inhibited the growth of Salmonella and EHEC. Cell-free supernatants of L. rhamnosus GG cultures significantly reduced the pathogen populations in microbiological media. Although not as effective as L. rhamnosus GG in inhibiting the growth of Salmonella and EHEC, the biocontrol agents were more effective in competing for attachment to vegetable seeds. The study observed the inhibition of human bacterial pathogens by competitive bacteria or their metabolites and the competitive attachment to sprout seeds among all bacteria involved. The results will help strategize interventions to produce vegetable seeds and seed sprouts free of foodborne pathogens.

scholarly journals Encapsulation of bacteriophage cocktail into chitosan for the treatment of bacterial diarrhea

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Golnar Rahimzadeh ◽  
Majid Saeedi ◽  
Mahmood Moosazadeh ◽  
Seyyed Mohammad Hassan Hashemi ◽  
Amirhossein Babaei ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Weight Loss ◽  
Biocontrol Agent ◽  
Shigella Flexneri ◽  
Treated Group ◽  
Therapeutic Effectiveness ◽  
Gastrointestinal Infection ◽  
Weight Changes ◽  
Gastrointestinal Infections ◽  
Lower Group

AbstractThe therapeutic effectiveness of a chitosan encapsulated bacteriophage cocktail as a smart biocontrol agent was evaluated in this study to be used as a preventative and treatment option for gastrointestinal infections. To evaluate the effect of the bacteriophage formulation on the treatment of gastrointestinal infection, rats were infected with Salmonella enterica, Shigella flexneri, and Escherichia coli. The rats were weighed and their stools cultured. The results showed that the group which had the chitosan encapsulated bacteriophage cocktail did not lose weight after 3 days and had significantly lower group weight changes. Weight loss was significant in the rats that had cefixime administered instead. Positive cultured stools were reduced after 4 days compared to 2 days in the treated group with the chitosan encapsulated bacteriophage cocktail. The chitosan encapsulated bacteriophage cocktail can therefore be effective in the treatment of gastrointestinal infections.

scholarly journals Pathovar Transcriptomes

mSystems ◽  
2017 ◽  
Vol 2 (4) ◽  
Author(s):  
Amy Platenkamp ◽  
Jay L. Mellies
Keyword(s):  
Gene Expression ◽  
Escherichia Coli ◽  
Regulatory Networks ◽  
Virulence Gene ◽  
Model System ◽  
Genomic Sequences ◽  
Bacterial Strains ◽  
Content Type ◽  
Virulence Gene Expression ◽  
Link Type

ABSTRACT Archetypal pathogenic bacterial strains are often used to elucidate regulatory networks of an entire pathovar, which encompasses multiple lineages and phylogroups. With enteropathogenic Escherichia coli (EPEC) as a model system, Hazen and colleagues (mSystems 6:e00024-17, 2017, https://doi.org/10.1128/mSystems.00024-17 ) used 9 isolates representing 8 lineages and 3 phylogroups to find that isolates with similar genomic sequences exhibit similarities in global transcriptomes under conditions of growth in medium that induces virulence gene expression, and they found variation among individual isolates. Archetypal pathogenic bacterial strains are often used to elucidate regulatory networks of an entire pathovar, which encompasses multiple lineages and phylogroups. With enteropathogenic Escherichia coli (EPEC) as a model system, Hazen and colleagues (mSystems 6:e00024-17, 2017, https://doi.org/10.1128/mSystems.00024-17 ) used 9 isolates representing 8 lineages and 3 phylogroups to find that isolates with similar genomic sequences exhibit similarities in global transcriptomes under conditions of growth in medium that induces virulence gene expression. They also found variation among individual isolates. Their work illustrates the importance of moving beyond observing regulatory phenomena of a limited number of regulons in a few archetypal strains, with the possibility of correlating clinical symptoms to key transcriptional pathways across lineages and phylogroups.

scholarly journals Bifidobacterium bifidum R0071 results in a greater proportion of healthy days and a lower percentage of academically stressed students reporting a day of cold/flu: a randomised, double-blind, placebo-controlled study

2015 ◽  
Vol 113 (3) ◽  
pp. 426-434 ◽  
Author(s):  
Bobbi Langkamp-Henken ◽  
Cassie C. Rowe ◽  
Amanda L. Ford ◽  
Mary C. Christman ◽  
Carmelo Nieves ◽  
...  
Keyword(s):  
Acute Stress ◽  
Bifidobacterium Longum ◽  
Daily Intake ◽  
Bifidobacterium Bifidum ◽  
Lactobacillus Helveticus ◽  
Lower Percentage ◽  
Controlled Study ◽  
Double Blind ◽  
Double Blind Placebo ◽  
Symptom Intensity

Acute psychological stress is positively associated with a cold/flu. The present randomised, double-blind, placebo-controlled study examined the effect of three potentially probiotic bacteria on the proportion of healthy days over a 6-week period in academically stressed undergraduate students (n 581) who received Lactobacillus helveticus R0052, Bifidobacterium longum ssp. infantis R0033, Bifidobacterium bifidum R0071 or placebo. On each day, participants recorded the intensity (scale: 0 = not experiencing to 3 = very intense) for nine cold/flu symptoms, and a sum of symptom intensity >6 was designated as a day of cold/flu. B. bifidum resulted in a greater proportion of healthy days than placebo (P≤ 0·05). The percentage of participants reporting ≥ 1 d of cold/flu during the 6-week intervention period was significantly lower with B. bifidum than with placebo (P< 0·05). There were no effects of B. infantis or L. helveticus compared with placebo on either outcome. A predictive model accounted for influential characteristics and their interactions on daily reporting of cold/flu episodes. The proportion of participants reporting a cold on any given day was lower at weeks 2 and 3 with B. bifidum and B. infantis than with placebo for the average level of stress and the most commonly reported number of hours of sleep. Daily intake of bifidobacteria provides benefit related to cold/flu outcomes during acute stress.

Sign in / Sign up

Export Citation Format

Share Document