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1.
J Cyst Fibros ; 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38702223

RESUMEN

BACKGROUND: Excessive inflammation and recurrent airway infections characterize people with cystic fibrosis (pwCF), a disease with highly heterogeneous clinical outcomes. How the overall immune response is affected in pwCF, its relationships with the lung microbiome, and the source of clinical heterogeneity have not been fully elucidated. METHODS: Peripheral blood and sputum samples were collected from 28 pwCF and an age-matched control group. Systemic immune cell subsets and surface markers were quantified using multiparameter flow cytometry. Lung microbiome composition was reconstructed using metatranscriptomics on sputum samples, and microbial taxa were correlated to circulating immune cells and surface markers expression. RESULTS: In pwCF, we found a specific systemic immune profile characterized by widespread hyperactivation and altered frequencies of several subsets. These included substantial changes in B-cell subsets, enrichment of CD35+/CD49d+ neutrophils, and reduction in dendritic cells. Activation markers and checkpoint molecule expression levels differed from healthy subjects. CTLA-4 expression was increased in Tregs and, together with impaired B-cell subsets, correlated with patients' lung function. Concentrations and frequencies of key immune cells and marker expression correlated with the relative abundance of commensal and pathogenic bacteria in the lungs. CONCLUSION: The CF-specific immune signature, involving hyperactivation, immune dysregulation with alteration in Treg homeostasis, and impaired B-cell function, is a potential source of lung function heterogeneity. The activity of specific microbes contributes to disrupting the balance of the immune response. Our data provide a unique foundation for identifying novel markers and immunomodulatory targets to develop the future of cystic fibrosis treatment and management.

2.
Biofilm ; 7: 100180, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38370152

RESUMEN

Antivirulence agents are considered a promising strategy to treat bacterial infections. Fluoropyrimidines possess antivirulence and antibiofilm activity against Gram-negative bacteria; however, their mechanism of action is yet unknown. Consistent with their known antibiofilm activity, fluoropyrimidines, particularly 5-fluorocytosine (5-FC), impair curli-dependent surface adhesion by Escherichia coli MG1655 via downregulation of curli fimbriae gene transcription. Curli inhibition requires fluoropyrimidine conversion into fluoronucleotides and is not mediated by c-di-GMP or the ymg-rcs envelope stress response axis, previously suggested as the target of fluorouracil antibiofilm activity in E. coli. In contrast, 5-FC hampered the transcription of curli activators RpoS and stimulated the expression of Fis, a curli repressor affected by nucleotide availability. This last observation suggested a possible perturbation of the de novo pyrimidine biosynthesis by 5-FC: indeed, exposure to 5-FC resulted in a ca. 2-fold reduction of UMP intracellular levels while not affecting ATP. Consistently, expression of the de novo pyrimidine biosynthesis genes carB and pyrB was upregulated in the presence of 5-FC. Our results suggest that the antibiofilm activity of fluoropyrimidines is mediated, at least in part, by perturbation of the pyrimidine nucleotide pool. We screened a genome library in search of additional determinants able to counteract the effects of 5-FC. We found that a DNA fragment encoding the unknown protein D8B36_18,480 and the N-terminal domain of the penicillin-binding protein 1b (PBP1b), involved in peptidoglycan synthesis, could restore curli production in the presence of 5-FC. Deletion of the PBP1b-encoding gene mrcB, induced csgBAC transcription, while overexpression of the gene encoding the D8B36_18,480 protein obliterated its expression, possibly as part of a coordinated response in curli regulation with PBP1b. While the two proteins do not appear to be direct targets of 5-FC, their involvement in curli regulation suggests a connection between peptidoglycan biosynthesis and curli production, which might become even more relevant upon pyrimidine starvation and reduced availability of UDP-sugars needed in cell wall biosynthesis. Overall, our findings link the antibiofilm activity of fluoropyrimidines to the redirection of at least two global regulators (RpoS, Fis) by induction of pyrimidine starvation. This highlights the importance of the de novo pyrimidines biosynthesis pathway in controlling virulence mechanisms in different bacteria and makes the pathway a potential target for antivirulence strategies.

4.
J Integr Complement Med ; 28(12): 965-968, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36103278

RESUMEN

Introduction: Recent cancer research highlighted specific patient needs, with a growing interest in integrative oncology (IO). Design: This is a narrative review concerning the Tuscan Healthcare System, which represents a virtuous example of progressive integration of complementary medicine in conventional cancer care. Results: The main steps of the process are described, with a specific focus on the 2021 Diagnostic and Therapeutic Care Pathway on Integrative Oncology. Conclusions: Implementing an IO service may contribute to respond to patients' demand for complementary therapies, also providing safety and equity of therapeutic access within public health care systems.


Asunto(s)
Neoplasias , Humanos , Neoplasias/diagnóstico , Atención a la Salud
5.
Microorganisms ; 10(6)2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-35744681

RESUMEN

Staphylococcus epidermidis is an opportunistic pathogen and a frequent cause of nosocomial infections. In this work, we show that, among 51 S. epidermidis isolates from an Italian hospital, only a minority displayed biofilm formation, regardless of their isolation source (peripheral blood, catheter, or skin wounds); however, among the biofilm-producing isolates, those from catheters were the most efficient in biofilm formation. Interestingly, most isolates including strong biofilm producers displayed production levels of PIA (polysaccharide intercellular adhesin), the main S. epidermidis extracellular polysaccharide, similar to reference S. epidermidis strains classified as non-biofilm formers, and much lower than those classified as intermediate or high biofilm formers, possibly suggesting that high levels of PIA production do not confer a particular advantage for clinical isolates. Finally, while for the reference S. epidermidis strains the biofilm production clearly correlated with the decreased sensitivity to antibiotics, in particular, protein synthesis inhibitors, in our clinical isolates, such positive correlation was limited to tetracycline. In contrast, we observed an inverse correlation between biofilm formation and the minimal inhibitory concentrations for levofloxacin and teicoplanin. In addition, in growth conditions favoring PIA production, the biofilm-forming isolates showed increased sensitivity to daptomycin, clindamycin, and erythromycin, with increased tolerance to the trimethoprim/sulfamethoxazole association. The lack of direct correlation between the biofilm production and increased tolerance to antibiotics in S. epidermidis isolates from a clinical setting would suggest, at least for some antimicrobials, the possible existence of a trade-off between the production of biofilm determinants and antibiotic resistance.

7.
Microorganisms ; 10(3)2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35336113

RESUMEN

In Crohn's disease (CD) patients, the adherent-invasive Escherichia coli (AIEC) pathovar contributes to the chronic inflammation typical of the disease via its ability to invade gut epithelial cells and to survive in macrophages. We show that, in the AIEC strain LF82, inactivation of the pyrD gene, encoding dihydroorotate dehydrogenase (DHOD), an enzyme of the de novo pyrimidine biosynthetic pathway, completely abolished its ability of to grow in a macrophage environment-mimicking culture medium. In addition, pyrD inactivation reduced flagellar motility and strongly affected biofilm formation by downregulating transcription of both type 1 fimbriae and curli subunit genes. Thus, the pyrD gene appears to be essential for several cellular processes involved in AIEC virulence. Interestingly, vidofludimus (VF), a DHOD inhibitor, has been proposed as an effective drug in CD treatment. Despite displaying a potentially similar binding mode for both human and E. coli DHOD in computational molecular docking experiments, VF showed no activity on either growth or virulence-related processes in LF82. Altogether, our results suggest that the crucial role played by the pyrD gene in AIEC virulence, and the presence of structural differences between E. coli and human DHOD allowing for the design of specific inhibitors, make E. coli DHOD a promising target for therapeutical strategies aiming at counteracting chronic inflammation in CD by acting selectively on its bacterial triggers.

9.
Nat Commun ; 12(1): 3186, 2021 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-34045458

RESUMEN

Long-term infection of the airways of cystic fibrosis patients with Pseudomonas aeruginosa is often accompanied by a reduction in bacterial growth rate. This reduction has been hypothesised to increase within-patient fitness and overall persistence of the pathogen. Here, we apply adaptive laboratory evolution to revert the slow growth phenotype of P. aeruginosa clinical strains back to a high growth rate. We identify several evolutionary trajectories and mechanisms leading to fast growth caused by transcriptional and mutational changes, which depend on the stage of adaptation of the strain. Return to high growth rate increases antibiotic susceptibility, which is only partially dependent on reversion of mutations or changes in the transcriptional profile of genes known to be linked to antibiotic resistance. We propose that similar mechanisms and evolutionary trajectories, in reverse direction, may be involved in pathogen adaptation and the establishment of chronic infections in the antibiotic-treated airways of cystic fibrosis patients.


Asunto(s)
Antibacterianos/farmacología , Fibrosis Quística/complicaciones , Farmacorresistencia Microbiana/genética , Evolución Molecular , Infecciones por Pseudomonas/tratamiento farmacológico , Pseudomonas aeruginosa/genética , Adaptación Fisiológica/efectos de los fármacos , Adaptación Fisiológica/genética , Antibacterianos/uso terapéutico , Proteínas Bacterianas/genética , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Fibrosis Quística/tratamiento farmacológico , Fibrosis Quística/inmunología , Fibrosis Quística/microbiología , Análisis Mutacional de ADN , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , Evolución Molecular Dirigida , Farmacorresistencia Microbiana/efectos de los fármacos , Regulación Bacteriana de la Expresión Génica , Aptitud Genética/efectos de los fármacos , Genoma Bacteriano , Humanos , Pulmón/inmunología , Pulmón/microbiología , Pruebas de Sensibilidad Microbiana , Mutación , Fenotipo , Infecciones por Pseudomonas/inmunología , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/aislamiento & purificación , Esputo/microbiología
10.
Cancer Cell ; 39(5): 708-724.e11, 2021 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-33798472

RESUMEN

Metastasis is facilitated by the formation of a "premetastatic niche," which is fostered by primary tumor-derived factors. Colorectal cancer (CRC) metastasizes mainly to the liver. We show that the premetastatic niche in the liver is induced by bacteria dissemination from primary CRC. We report that tumor-resident bacteria Escherichia coli disrupt the gut vascular barrier (GVB), an anatomical structure controlling bacterial dissemination along the gut-liver axis, depending on the virulence regulator VirF. Upon GVB impairment, bacteria disseminate to the liver, boost the formation of a premetastatic niche, and favor the recruitment of metastatic cells. In training and validation cohorts of CRC patients, we find that the increased levels of PV-1, a marker of impaired GVB, is associated with liver bacteria dissemination and metachronous distant metastases. Thus, PV-1 is a prognostic marker for CRC distant recurrence and vascular impairment, leading to liver metastases.


Asunto(s)
Neoplasias Colorrectales/irrigación sanguínea , Neoplasias Colorrectales/patología , Neoplasias Hepáticas/patología , Metástasis de la Neoplasia/patología , Recurrencia Local de Neoplasia/patología , Bacterias/aislamiento & purificación , Neoplasias del Colon/irrigación sanguínea , Neoplasias del Colon/patología , Humanos , Hígado/patología , Neoplasias Hepáticas/secundario
11.
Integr Cancer Ther ; 20: 15347354211004730, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33784850

RESUMEN

In June 2019, a meeting was held in Paris in which experts from different countries (Israel, Spain, Belgium, Italy, USA, and France) met to discuss a selection of topics in integrative oncology (IO). The objectives were to draw on the delegates' experience and expertise to begin an international collaboration, sharing details of differing existing models and discussing future perspectives to help define and guide practice in IO and define unmet needs. This report presents a summary of the meeting's main presentations, and also reports on the experts' responses to a questionnaire examining different aspects of IO service delivery, infrastructure, and utilization.


Asunto(s)
Terapias Complementarias , Oncología Integrativa , Humanos , Internacionalidad , Italia , Encuestas y Cuestionarios
12.
Nat Rev Microbiol ; 19(5): 331-342, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33214718

RESUMEN

Intense genome sequencing of Pseudomonas aeruginosa isolates from cystic fibrosis (CF) airways has shown inefficient eradication of the infecting bacteria, as well as previously undocumented patient-to-patient transmission of adapted clones. However, genome sequencing has limited potential as a predictor of chronic infection and of the adaptive state during infection, and thus there is increasing interest in linking phenotypic traits to the genome sequences. Phenotypic information ranges from genome-wide transcriptomic analysis of patient samples to determination of more specific traits associated with metabolic changes, stress responses, antibiotic resistance and tolerance, biofilm formation and slow growth. Environmental conditions in the CF lung shape both genetic and phenotypic changes of P. aeruginosa during infection. In this Review, we discuss the adaptive and evolutionary trajectories that lead to early diversification and late convergence, which enable P. aeruginosa to succeed in this niche, and we point out how knowledge of these biological features may be used to guide diagnosis and therapy.


Asunto(s)
Fibrosis Quística/microbiología , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/fisiología , Evolución Biológica , Genoma Bacteriano , Humanos
13.
Homeopathy ; 109(3): 167-168, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32643783

RESUMEN

During the COVID-19 epidemic in Italy, hospital outpatient clinics progressively decreased their activities; in March 2020 they were closed except for emergencies. During this period, the activities of the public Homeopathy Outpatient Clinic of Lucca aimed at guaranteeing therapeutic continuity to patients by means of telephone or video consultations, and searching for homeopathic medicines that best responded to early COVID-19 symptoms. In March 2020, the Complementary Medicine Working Group participated in the organization of a mission of COVID-19 Chinese experts for the online training of professionals working in the Tuscan Healthcare System. The medical staff of the Lucca Clinic also cooperated in telephone health surveillance of infected patients at home, seroprevalence investigations using the capillary blood rapid test, and the implementation of the CLIFICOL (Clinical Files Collection) project.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/terapia , Materia Medica/uso terapéutico , Neumonía Viral/terapia , Telemedicina/organización & administración , Actitud Frente a la Salud , COVID-19 , Homeopatía , Humanos , Italia , Pandemias , SARS-CoV-2
14.
Sci Transl Med ; 11(488)2019 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-30996083

RESUMEN

Filamentous bacteriophage (Pf phage) contribute to the virulence of Pseudomonas aeruginosa infections in animal models, but their relevance to human disease is unclear. We sought to interrogate the prevalence and clinical relevance of Pf phage in patients with cystic fibrosis (CF) using sputum samples from two well-characterized patient cohorts. Bacterial genomic analysis in a Danish longitudinal cohort of 34 patients with CF revealed that 26.5% (n = 9) were consistently Pf phage positive. In the second cohort, a prospective cross-sectional cohort of 58 patients with CF at Stanford, sputum qPCR analysis showed that 36.2% (n = 21) of patients were Pf phage positive. In both cohorts, patients positive for Pf phage were older, and in the Stanford CF cohort, patients positive for Pf phage were more likely to have chronic P. aeruginosa infection and had greater declines in pulmonary function during exacerbations than patients negative for Pf phage presence in the sputum. Last, P. aeruginosa strains carrying Pf phage exhibited increased resistance to antipseudomonal antibiotics. Mechanistically, in vitro analysis showed that Pf phage sequesters these same antibiotics, suggesting that this mechanism may thereby contribute to the selection of antibiotic resistance over time. These data provide evidence that Pf phage may contribute to clinical outcomes in P. aeruginosa infection in CF.


Asunto(s)
Fibrosis Quística/microbiología , Pulmón/microbiología , Pseudomonas/patogenicidad , Animales , Antibacterianos/farmacología , Estudios Transversales , Farmacorresistencia Microbiana/genética , Farmacorresistencia Microbiana/fisiología , Humanos , Inovirus , Pruebas de Sensibilidad Microbiana , Estudios Prospectivos
15.
Integr Cancer Ther ; 18: 1534735418823266, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30791736

RESUMEN

Interest in integrative oncology (IO) is growing globally. Patients with cancer are actively using traditional complementary and integrative medicine (TCIM) as part of their cancer and survivorship care. Published studies from around the world report increasing use of TCIM by people living with cancer. This article summarizes the presentations that took place during a symposium titled, "Integrative Oncology: International Perspectives" at the International Research Congress on Integrative Medicine and Health in Baltimore, 2018. The purpose of the presentations was to examine whether cancer services across a variety of geographical regions, including Australia, Canada, the United States, and the European Union, were actively responding to cancer survivors' demand for TCIM. The presenters highlighted utilization rates and both facilitators and barriers to the provision of IO services in their respective countries and regions. The audience discussion following the presentations drew out many noteworthy perspectives.


Asunto(s)
Terapias Complementarias/estadística & datos numéricos , Medicina Integrativa/estadística & datos numéricos , Oncología Integrativa/estadística & datos numéricos , Neoplasias/tratamiento farmacológico , Supervivientes de Cáncer/estadística & datos numéricos , Humanos , Internacionalidad , Encuestas y Cuestionarios
16.
J Altern Complement Med ; 24(9-10): 933-941, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30247968

RESUMEN

BACKGROUND: To address the side effects of anticancer treatments, the Clinic for Complementary Medicine and Diet in Oncology was opened, in collaboration with the oncology department, at the Hospital of Lucca (Italy) in 2013. AIM: To present the results of complementary medicine treatment targeted toward reducing the adverse effects of anticancer therapy and cancer symptoms, and improving patient quality of life. Dietary advice was aimed at the reduction of foods that promote inflammation in favor of those with antioxidant and anti-inflammatory properties. METHODS: This is a retrospective observational study on 357 patients consecutively visited from September 2013 to December 2017. The intensity of symptoms was evaluated according to a grading system from G0 (absent) to G1 (slight), G2 (moderate), and G3 (strong). The severity of radiodermatitis was evaluated with the Radiation Therapy Oncology Group (RTOG) scale. Almost all the patients (91.6%) were receiving or had just finished some form of conventional anticancer therapy. RESULTS: The main types of cancer were breast (57.1%), colon (7.3%), lung (5.0%), ovary (3.9%), stomach (2.5%), prostate (2.2%), and uterus (2.5%). Comparison of clinical conditions before and after treatment showed a significant amelioration of nausea, insomnia, depression, anxiety, fatigue, mucositis, hot flashes, joint pain, dysgeusia, neuropathy, and all symptoms. Moreover, in a subgroup of 17 patients in radiotherapy undergoing integrative treatment, the level of toxicities and the severity of radiodermatitis were much lower than in the 13 patients without integrative treatment. Twenty-one cancer patients (6.2%) either refused (18) or discontinued (3) conventional anticancer treatment against the recommendation of their oncologist; after the integrative oncology (IO) visit, 7 (41.2%) out of 17 patients with follow-up decided to accept standard oncologic treatments. CONCLUSIONS: An IO clinic may contribute to reducing the adverse effects of anticancer therapy and improving the quality of life of cancer patients.


Asunto(s)
Antineoplásicos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/terapia , Medicina Integrativa , Oncología Integrativa , Neoplasias/terapia , Adulto , Anciano , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Terapias Complementarias , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
17.
Nat Commun ; 9(1): 3459, 2018 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-30150613

RESUMEN

Life-long bacterial infections in cystic fibrosis (CF) airways constitute an excellent model both for persistent infections and for microbial adaptive evolution in complex dynamic environments. Using high-resolution transcriptomics applied on CF sputum, we profile transcriptional phenotypes of Pseudomonas aeruginosa populations in patho-physiological conditions. Here we show that the soft-core genome of genetically distinct populations, while maintaining transcriptional flexibility, shares a common expression program tied to the lungs environment. We identify genetically independent traits defining P. aeruginosa physiology in vivo, documenting the connection between several previously identified mutations in CF isolates and some of the convergent phenotypes known to develop in later stages of the infection. In addition, our data highlight to what extent this organism can exploit its extensive repertoire of physiological pathways to acclimate to a new niche and suggest how alternative nutrients produced in the lungs may be utilized in unexpected metabolic contexts.


Asunto(s)
Fibrosis Quística/genética , Pulmón/metabolismo , Mutación/genética , Pseudomonas aeruginosa/genética , Transcriptoma/genética , Adulto , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Secuenciación Completa del Genoma/métodos
18.
Sci Rep ; 8(1): 12512, 2018 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-30131514

RESUMEN

In 474 genome sequenced Pseudomonas aeruginosa isolates from 34 cystic fibrosis (CF) patients, 40% of these harbor mutations in the mexZ gene encoding a negative regulator of the MexXY-OprM efflux pump associated with aminoglycoside and fluoroquinolone resistance. Surprisingly, resistance to aminoglycosides and fluoroquinolones of mexZ mutants was far below the breakpoint of clinical resistance. However, the fitness increase of the mutant bacteria in presence of the relevant antibiotics, as demonstrated in competition experiments between mutant and ancestor bacteria, showed that 1) very small phenotypic changes cause significant fitness increase with severe adaptive consequences, and 2) standardized phenotypic tests fail to detect such low-level variations. The frequent appearance of P. aeruginosa mexZ mutants in CF patients is directly connected to the intense use of the target antibiotics, and low-level antibiotic resistance, if left unnoticed, can result in accumulation of additional genetic changes leading to high-level resistance.


Asunto(s)
Proteínas Bacterianas/genética , Fibrosis Quística/microbiología , Farmacorresistencia Microbiana , Mutación , Pseudomonas aeruginosa/genética , Adaptación Fisiológica , Aminoglicósidos/farmacología , Antibacterianos/farmacología , Fibrosis Quística/tratamiento farmacológico , Fluoroquinolonas/farmacología , Aptitud Genética , Humanos , Fenotipo , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/crecimiento & desarrollo , Análisis de Secuencia de ARN , Secuenciación Completa del Genoma/métodos
19.
Front Microbiol ; 9: 238, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29497413

RESUMEN

The small RNA ErsA of Pseudomonas aeruginosa was previously suggested to be involved in biofilm formation via negative post-transcriptional regulation of the algC gene that encodes the virulence-associated enzyme AlgC, which provides sugar precursors for the synthesis of several polysaccharides. In this study, we show that a knock-out ersA mutant strain forms a flat and uniform biofilm, not characterized by mushroom-multicellular structures typical of a mature biofilm. Conversely, the knock-out mutant strain showed enhanced swarming and twitching motilities. To assess the influence of ErsA on the P. aeruginosa transcriptome, we performed RNA-seq experiments comparing the knock-out mutant with the wild-type. More than 160 genes were found differentially expressed in the knock-out mutant. Parts of these genes, important for biofilm formation and motility regulation, are known to belong also to the AmrZ transcriptional regulator regulon. Here, we show that ErsA binds in vitro and positively regulates amrZ mRNA at post-transcriptional level in vivo suggesting an interesting contribution of the ErsA-amrZ mRNA interaction in biofilm development at several regulatory levels.

20.
Crit Rev Microbiol ; 44(1): 1-30, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28485690

RESUMEN

Escherichia coli can commonly be found, either as a commensal, probiotic or a pathogen, in the human gastrointestinal (GI) tract. Biofilm formation and its regulation is surprisingly variable, although distinct regulatory pattern of red, dry and rough (rdar) biofilm formation arise in certain pathovars and even clones. In the GI tract, environmental conditions, signals from the host and from commensal bacteria contribute to shape E. coli biofilm formation within the multi-faceted multicellular communities in a complex and integrated fashion. Although some major regulatory networks, adhesion factors and extracellular matrix components constituting E. coli biofilms have been recognized, these processes have mainly been characterized in vitro and in the context of interaction of E. coli strains with intestinal epithelial cells. However, direct observation of E. coli cells in situ, and the vast number of genes encoding surface appendages on the core or accessory genome of E. coli suggests the complexity of the biofilm process to be far from being fully understood. In this review, we summarize biofilm formation mechanisms of commensal, probiotic and pathogenic E. coli in the context of the gastrointestinal tract.


Asunto(s)
Biopelículas , Escherichia coli/fisiología , Tracto Gastrointestinal/microbiología , Animales , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Tracto Gastrointestinal/inmunología , Regulación Bacteriana de la Expresión Génica , Humanos
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