scholarly journals Production of catechol siderophores by bacteria selected from feces of a healthy female adult through screening NRPS A domain

2020 ◽  
Author(s):  
Huiling Hu ◽  
Yihe Wu ◽  
Minai Zhang ◽  
Qing Zhang ◽  
Huan Wang ◽  
...  
Keyword(s):  
Iron Nutrition ◽  
Human Gastrointestinal Tract ◽  
Human Gut ◽  
Activity Prediction ◽  
Female Adult ◽  
E Coli ◽  
Peptide Synthetases ◽  
Healthy Female ◽  
Nutrition Balance

Abstract Background: Catechol siderophores, which are widespread in the human gastrointestinal tract (GIT) and play important roles in maintaining iron-nutrition balance between microorganisms and host, are small molecules with a high affinity for ferric iron and are assembled by nonribosomal peptide synthetases (NRPS). In this study, we select strains encoding NRPS A domain gene from feces of a health female adult, predict its products type, and check it out in vitro . Results: Firstly, eight bacteria were determined encoding NRPS A domain gene, and then two kind of catechol siderophores, Bacillibactin and Enterobactin, were predicted according to NRPS A domain substrate specificity. Secondly, Bacillibactin and Enterobactin were checked out in cultured medium aerobic incubated with selected strains of E. Coli, Bacillus sp. and B. Cereus. For the yield of catechol siderophores, B. cereus Gut 16 secreted highest yield of Bacillibactin and E. coli Gut 07 produce highest yield of Enterobactin. Conclusion: By presence determination and activity prediction of NRPS A domain, two siderophores, Bacillibactin and Enterobactin, were checked out finally being secreted by selected strains cultured in a aerobic medium. Further research on the potential probiotic property is necessary to affirm the application in biological industry, as well as to elucidate their mechanism in human gut. Keywords : Catechol siderophores, Enterobactin, Bacillibactin, NRPS A domain, Feces, Probiotics

scholarly journals Biochemical traits that Escherichia coli evolved during its adaption to the gastrointestinal tract of humans

2019 ◽  
Author(s):  
Wenfa Ng
Keyword(s):  
Escherichia Coli ◽  
Gastrointestinal Tract ◽  
Selection Pressure ◽  
Human Gastrointestinal Tract ◽  
Human Gut ◽  
Multiple Sequence ◽  
E Coli ◽  
Starting Point ◽  
Altered Gene ◽  
Different Strains

What biochemical tricks did Escherichia coli obtained or evolved during its time as a commensal in the human gastrointestinal system? E. coli is a natural symbiont of the human gastrointestinal tract. Thus, through evolutionary timescales, the bacterium must have co-evolved with humans with conditions in the gastrointestinal tract serving as selection pressure for the evolution of a variety of biochemical and physiological adaptations. These adaptations came about through mutations that arise in the genome, and thus, could be retrospectively profiled to understand the differing evolutionary pressure that selected for specific traits in the bacterium useful for its survival in the changing conditions of the human gut. Using sequenced and annotated genome information of different strains of E. coli as a guide and starting point, possibility exists to use a combination of bioinformatics, biochemical, and genetic approaches to decipher the biochemical tricks that E. coli evolved or pick up during its time as a commensal in the human gastrointestinal tract. Specifically, sequenced genomes serve as a molecular fossil from which we could obtain imprints of the various evolutionary events that impact on the bacterium. Adaptations to changing conditions could also be deciphered through analysis of single nucleotide polymorphism (SNPs). Comparison of the profiled mutations and altered gene sequences between different E. coli strains with different co-evolutionary history with the human gut might help reveal the different length of time in which different E. coli strains have co-evolved with humans. More importantly, multiple sequence alignment and phylogenetic analysis could also reveal which genes first evolve due to selection pressure exerted on the bacterium by fluctuating environmental conditions in the human gut. Genetic knockdowns of the putative genes would help indicate the overall essentiality of the genes to the physiology and functioning of the modern E. coli bacterium. The approach outlined should help answer some of the most fundamental questions regarding the evolution of different E. coli strains as well as how natural selection exerts its influence on the physiology of a commensal organism with respect to host adaptation.

scholarly journals Modulation of Enterohaemorrhagic Escherichia coli Survival and Virulence in the Human Gastrointestinal Tract

2018 ◽  
Vol 6 (4) ◽  
pp. 115 ◽  
Author(s):  
Grégory Jubelin ◽  
Mickaël Desvaux ◽  
Stephanie Schüller ◽  
Lucie Etienne-Mesmin ◽  
Maite Muniesa ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Gastrointestinal Tract ◽  
Gut Microbiota ◽  
Model Systems ◽  
In Vivo Studies ◽  
Low Oxygen ◽  
Human Gastrointestinal Tract ◽  
Human Gut ◽  
Enterohaemorrhagic Escherichia Coli

Enterohaemorrhagic Escherichia coli (EHEC) is a major foodborne pathogen responsible for human diseases ranging from diarrhoea to life-threatening complications. Survival of the pathogen and modulation of virulence gene expression along the human gastrointestinal tract (GIT) are key features in bacterial pathogenesis, but remain poorly described, due to a paucity of relevant model systems. This review will provide an overview of the in vitro and in vivo studies investigating the effect of abiotic (e.g., gastric acid, bile, low oxygen concentration or fluid shear) and biotic (e.g., gut microbiota, short chain fatty acids or host hormones) parameters of the human gut on EHEC survival and/or virulence (especially in relation with motility, adhesion and toxin production). Despite their relevance, these studies display important limitations considering the complexity of the human digestive environment. These include the evaluation of only one single digestive parameter at a time, lack of dynamic flux and compartmentalization, and the absence of a complex human gut microbiota. In a last part of the review, we will discuss how dynamic multi-compartmental in vitro models of the human gut represent a novel platform for elucidating spatial and temporal modulation of EHEC survival and virulence along the GIT, and provide new insights into EHEC pathogenesis.

scholarly journals Biochemical traits that Escherichia coli evolved during its adaption to the gastrointestinal tract of humans

2019 ◽  
Author(s):  
Wenfa Ng
Keyword(s):  
Escherichia Coli ◽  
Gastrointestinal Tract ◽  
Selection Pressure ◽  
Human Gastrointestinal Tract ◽  
Human Gut ◽  
Multiple Sequence ◽  
E Coli ◽  
Starting Point ◽  
Altered Gene ◽  
Different Strains

What biochemical tricks did Escherichia coli obtained or evolved during its time as a commensal in the human gastrointestinal system? E. coli is a natural symbiont of the human gastrointestinal tract. Thus, through evolutionary timescales, the bacterium must have co-evolved with humans with conditions in the gastrointestinal tract serving as selection pressure for the evolution of a variety of biochemical and physiological adaptations. These adaptations came about through mutations that arise in the genome, and thus, could be retrospectively profiled to understand the differing evolutionary pressure that selected for specific traits in the bacterium useful for its survival in the changing conditions of the human gut. Using sequenced and annotated genome information of different strains of E. coli as a guide and starting point, possibility exists to use a combination of bioinformatics, biochemical, and genetic approaches to decipher the biochemical tricks that E. coli evolved or pick up during its time as a commensal in the human gastrointestinal tract. Specifically, sequenced genomes serve as a molecular fossil from which we could obtain imprints of the various evolutionary events that impact on the bacterium. Adaptations to changing conditions could also be deciphered through analysis of single nucleotide polymorphism (SNPs). Comparison of the profiled mutations and altered gene sequences between different E. coli strains with different co-evolutionary history with the human gut might help reveal the different length of time in which different E. coli strains have co-evolved with humans. More importantly, multiple sequence alignment and phylogenetic analysis could also reveal which genes first evolve due to selection pressure exerted on the bacterium by fluctuating environmental conditions in the human gut. Genetic knockdowns of the putative genes would help indicate the overall essentiality of the genes to the physiology and functioning of the modern E. coli bacterium. The approach outlined should help answer some of the most fundamental questions regarding the evolution of different E. coli strains as well as how natural selection exerts its influence on the physiology of a commensal organism with respect to host adaptation.

scholarly journals Bifidobacterium longum subsp. infantis CECT7210 (B. infantis IM-1®) Displays In Vitro Activity against Some Intestinal Pathogens

Nutrients ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3259
Author(s):  
Lorena Ruiz ◽  
Ana Belén Flórez ◽  
Borja Sánchez ◽  
José Antonio Moreno-Muñoz ◽  
Maria Rodriguez-Palmero ◽  
...  
Keyword(s):  
Infant Health ◽  
Bifidobacterium Longum ◽  
Probiotic Strain ◽  
Intestinal Cell ◽  
Human Gastrointestinal Tract ◽  
E Coli ◽  
Intestinal Cell Line ◽  
Intestinal Pathogens ◽  
Health Promoting

Certain non-digestible oligosaccharides (NDO) are specifically fermented by bifidobacteria along the human gastrointestinal tract, selectively favoring their growth and the production of health-promoting metabolites. In the present study, the ability of the probiotic strain Bifidobacterium longum subsp. infantis CECT7210 (herein referred to as B. infantis IM-1®) to utilize a large range of oligosaccharides, or a mixture of oligosaccharides, was investigated. The strain was able to utilize all prebiotics screened. However, galactooligosaccharides (GOS), and GOS-containing mixtures, effectively increased its growth to a higher extent than the other prebiotics. The best synbiotic combination was used to examine the antimicrobial activity against Escherichia coli, Cronobacter sakazakii, Listeria monocytogenes and Clostridium difficile in co-culture experiments. C. difficile was inhibited by the synbiotic, but it failed to inhibit E. coli. Moreover, Cr. sakazakii growth decreased during co-culture with B. infantis IM-1®. Furthermore, adhesion experiments using the intestinal cell line HT29 showed that the strain IM-1® was able to displace some pathogens from the enterocyte layer, especially Cr. sakazakii and Salmonella enterica, and prevented the adhesion of Cr. sakazakii and Shigella sonnei. In conclusion, a new synbiotic (probiotic strain B. infantis IM-1® and GOS) appears to be a potential effective supplement for maintaining infant health. However, further studies are needed to go more deeply into the mechanisms that allow B.infantis IM-1® to compete with enteropathogens.

In vitro study of the interaction between human gut microbiota and herbal extracts using willow bark extract as an example

Planta Medica ◽  
2016 ◽  
Vol 81 (S 01) ◽  
pp. S1-S381
Author(s):  
EM Pferschy-Wenzig ◽  
K Koskinen ◽  
C Moissl-Eichinger ◽  
R Bauer
Keyword(s):  
Gut Microbiota ◽  
In Vitro Study ◽  
Vitro Study ◽  
Bark Extract ◽  
Herbal Extracts ◽  
Human Gut ◽  
Human Gut Microbiota ◽  
Willow Bark

Metabolization of the herbal combination STW-5 by human gut microbiota in vitro

2017 ◽  
Author(s):  
EM Pferschy-Wenzig ◽  
A Roßmann ◽  
K Koskinen ◽  
H Abdel-Aziz ◽  
C Moissl-Eichinger ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Human Gut ◽  
Human Gut Microbiota

Rapid, Refined, and Robust Method for Expression, Purification, and Characterization of Recombinant Human Amyloid-beta M1-42

2019 ◽  
Author(s):  
Priya Prakash ◽  
Travis Lantz ◽  
Krupal P. Jethava ◽  
Gaurav Chopra
Keyword(s):  
Amyloid Beta ◽  
Western Blots ◽  
Force Microscopy ◽  
E Coli ◽  
Atomic Force ◽  
Set Up ◽  
Short Time

Amyloid plaques found in the brains of Alzheimer’s disease (AD) patients primarily consists of amyloid beta 1-42 (Ab42). Commercially, Ab42 is synthetized using peptide synthesizers. We describe a robust methodology for expression of recombinant human Ab(M1-42) in Rosetta(DE3)pLysS and BL21(DE3)pLysS competent E. coli with refined and rapid analytical purification techniques. The peptide is isolated and purified from the transformed cells using an optimized set-up for reverse-phase HPLC protocol, using commonly available C18 columns, yielding high amounts of peptide (~15-20 mg per 1 L culture) in a short time. The recombinant Ab(M1-42) forms characteristic aggregates similar to synthetic Ab42 aggregates as verified by western blots and atomic force microscopy to warrant future biological use. Our rapid, refined, and robust technique to purify human Ab(M1-42) can be used to synthesize chemical probes for several downstream in vitro and in vivo assays to facilitate AD research.

Антимикробная активность лиофилизированного водного извлечения Caragana jubata (Pall.) Poir.

2020 ◽  
Vol 54 (3) ◽  
pp. 42-44
Author(s):  
Павел Алексеевич Какорин ◽  
Татьяна Владимировна Фатеева ◽  
Ольга Ивановна Терешкина ◽  
Ирина Борисовна Перова ◽  
Галина Владиславовна Раменская ◽  
...  
Keyword(s):  
E Coli

На основании ранее проведенных исследований установлен профиль флавоноидов лиофилизированного водного извлечения, полученного из побегов C. jubata. В связи с тем, что, согласно данным литературы, флавоноиды являются потенциальными ингибиторами микроорганизмов, проведено изучение антимикробной активности лиофилизата в опытах in vitro с использованием скринигового метода определения антимикробной активности для препаратов растительного происхождения. При изучении бактериостатической и фунгистатической активности в опытах in vitro использовали метод двукратного серийного разведения препаратов в жидких питательных средах. В результате исследования лиофилизированного водного извлечения караганы гривастой установлено наличие умеренной антимикробной активности в отношении всех изученных штаммов патогенных микроорганизмов: грамположительных и грамотрицательных бактерий (S. aureus, E. coli, P. vulgaris, P. aeruginosa), дрожжеподобных и мицелиальных грибов (C. albicans, M. canis). Полученные данные позволяют рекомендовать лиофилизированное водное извлечение караганы гривастой для создания на его основе лекарственных форм наружного применения для лечения заболеваний кожи и слизистых оболочек, связанных с бактериальным воспалительным процессом.

Влияние in vitro изолированного и сочетанного с антибактериальными средствами применения бовгиалуронидазы азоксимер на целостность бактериальной биопленки и жизнеспосоность микроорганизмов

2020 ◽  
Vol 83 (2) ◽  
pp. 38-44
Author(s):  
Е. Ю. Тризна ◽  
Д. Р. Байдамшина ◽  
Александр А. Виницкий ◽  
А. Р. Каюмов
Keyword(s):  
E Coli

Исследована способность лиофилизата бовгиалуронидазы азоксимера («Лонгидаза») разрушать бактериальные биопленки S. aureus, E. faecalis, E. coli, а также сочетанное действие препарата с антибактериальными средствами. Показано, что 2 ч инкубации бовгиалуронидазы азоксимер в концентрации 750 – 1500 МЕ/мл вызывает двукратное снижение биомассы матрикса зрелых биопленок E. faecalis и E. coli, и на 60 % — S. aureus. Данный ферментный препарат не влияет на образование бактериальных биопленок. При сочетанном применении с антибактериальными средствами препарат повышает их эффективность в отношении бактерий в составе биопленок. Так, концентрация ципро-флоксацина и амоксициллина, необходимая для снижения количества КОЕ на 3 порядка в биопленке E. faecalis, в присутствии бовгиалуронидазы азоксимера снижается в 16 раз (p < 0,05). В присутствии фермента в 16 раз меньшие концентрации цефуроксима, фосфомицина, ципрофлоксацина и амикацина достаточны для снижения количества КОЕ на 3 порядка в биопленке E. coli (p < 0,05), и в значительно меньшей концентрации цефуроксим оказывает бактерицидное действие на клетки в биопленке S. aureus (p < 0,05). Вероятно, бовгиалуронидаза азоксимер увеличивает проникновение антибактериальных средств к клеткам бактерий в биопленке, что обеспечивает потенцирование их антибактериального эффекта. Такое действие ферментного препарата позволяет снизить дозу и повысить безопасность антибактериальных средств при сохранении их эффективности.

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