scholarly journals Production of Cellulose and Curli Fimbriae by Members of the Family Enterobacteriaceae Isolated from the Human Gastrointestinal Tract

2003 ◽  
Vol 71 (7) ◽  
pp. 4151-4158 ◽  
Author(s):  
Xhavit Zogaj ◽  
Werner Bokranz ◽  
Manfred Nimtz ◽  
Ute Römling

ABSTRACT Citrobacter spp., Enterobacter spp., and Klebsiella spp. isolated from the human gut were investigated for the biosynthesis of cellulose and curli fimbriae (csg). While Citrobacter spp. produced curli fimbriae and cellulose and Enterobacter spp. produced cellulose with various temperature-regulatory programs, Klebsiella spp. did not show pronounced expression of those extracellular matrix components. Investigation of multicellular behavior in two Citrobacter species and Enterobacter sakazakii showed an extracellular matrix, cell clumping, pellicle formation, and biofilm formation associated with the expression of cellulose and curli fimbriae. In those three strains, the csgD-csgBA region and the cellulose synthase gene bcsA were conserved. PCR screening for the presence of csgD, csgA and bcsA revealed that besides Klebsiella pneumoniae and Klebsiella oxytoca, all species investigated harbored the genetic information for expression of curli fimbriae and cellulose. Since Citrobacter spp., Enterobacter spp., and Klebsiella spp. are frequently found to cause biofilm-related infections such as catheter-associated urinary tract infections, the human gut could serve as a reservoir for dissemination of biofilm-forming isolates.

2016 ◽  
Vol 84 (5) ◽  
pp. 1491-1500 ◽  
Author(s):  
Maria Camila Montealegre ◽  
Kavindra V. Singh ◽  
Sudha R. Somarajan ◽  
Puja Yadav ◽  
Chungyu Chang ◽  
...  

Enterococcus faeciumis an important cause of hospital-associated infections, including urinary tract infections (UTIs), bacteremia, and infective endocarditis. Pili have been shown to play a role in the pathogenesis of Gram-positive bacteria, includingE. faecium. We previously demonstrated that a nonpiliated ΔempABC::catderivative ofE. faeciumTX82 was attenuated in biofilm formation and in a UTI model. Here, we studied the contributions of the individual pilus subunits EmpA, EmpB, and EmpC to pilus architecture, biofilm formation, adherence to extracellular matrix (ECM) proteins, and infection. We identified EmpA as the tip of the pili and found that deletion ofempAreduced biofilm formation to the same level as deletion of theempABCoperon, a phenotype that was restored by reconstitutingin situtheempAgene. Deletion ofempBalso caused a reduction in biofilm, while EmpC was found to be dispensable. Significant reductions in adherence to fibrinogen and collagen type I were observed with deletion ofempAandempB, while deletion ofempChad no adherence defect. Furthermore, we showed that each deletion mutant was significantly attenuated in comparison to the isogenic parental strain, TX82, in a mixed-inoculum UTI model (P< 0.001 to 0.048), that reconstitution ofempArestored virulence in the UTI model, and that deletion ofempAalso resulted in attenuation in an infective endocarditis model (P= 0.0088). Our results indicate that EmpA and EmpB, but not EmpC, contribute to biofilm and adherence to ECM proteins; however, all the Emp pilins are important forE. faeciumto cause infection in the urinary tract.


Biomolecules ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 349
Author(s):  
Nausika Betriu ◽  
Juan Bertran-Mas ◽  
Anna Andreeva ◽  
Carlos E. Semino

Pancreatic Ductal Adenocarcinoma (PDAC) is a fatal disease with poor prognosis because patients rarely express symptoms in initial stages, which prevents early detection and diagnosis. Syndecans, a subfamily of proteoglycans, are involved in many physiological processes including cell proliferation, adhesion, and migration. Syndecans are physiologically found in many cell types and their interactions with other macromolecules enhance many pathways. In particular, extracellular matrix components, growth factors, and integrins collect the majority of syndecans associations acting as biochemical, physical, and mechanical transducers. Syndecans are transmembrane glycoproteins, but occasionally their extracellular domain can be released from the cell surface by the action of matrix metalloproteinases, converting them into soluble molecules that are capable of binding distant molecules such as extracellular matrix (ECM) components, growth factor receptors, and integrins from other cells. In this review, we explore the role of syndecans in tumorigenesis as well as their potential as therapeutic targets. Finally, this work reviews the contribution of syndecan-1 and syndecan-2 in PDAC progression and illustrates its potential to be targeted in future treatments for this devastating disease.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Osvaldo Contreras ◽  
Fabio M. V. Rossi ◽  
Marine Theret

AbstractStriated muscle is a highly plastic and regenerative organ that regulates body movement, temperature, and metabolism—all the functions needed for an individual’s health and well-being. The muscle connective tissue’s main components are the extracellular matrix and its resident stromal cells, which continuously reshape it in embryonic development, homeostasis, and regeneration. Fibro-adipogenic progenitors are enigmatic and transformative muscle-resident interstitial cells with mesenchymal stem/stromal cell properties. They act as cellular sentinels and physiological hubs for adult muscle homeostasis and regeneration by shaping the microenvironment by secreting a complex cocktail of extracellular matrix components, diffusible cytokines, ligands, and immune-modulatory factors. Fibro-adipogenic progenitors are the lineage precursors of specialized cells, including activated fibroblasts, adipocytes, and osteogenic cells after injury. Here, we discuss current research gaps, potential druggable developments, and outstanding questions about fibro-adipogenic progenitor origins, potency, and heterogeneity. Finally, we took advantage of recent advances in single-cell technologies combined with lineage tracing to unify the diversity of stromal fibro-adipogenic progenitors. Thus, this compelling review provides new cellular and molecular insights in comprehending the origins, definitions, markers, fate, and plasticity of murine and human fibro-adipogenic progenitors in muscle development, homeostasis, regeneration, and repair.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Shaohua Wu ◽  
Vikas Kumar ◽  
Peng Xiao ◽  
Mitchell Kuss ◽  
Jung Yul Lim ◽  
...  

AbstractHeart valve disease is a common manifestation of cardiovascular disease and is a significant cause of cardiovascular morbidity and mortality worldwide. The pulmonary valve (PV) is of primary concern because of its involvement in common congenital heart defects, and the PV is usually the site for prosthetic replacement following a Ross operation. Although effects of age on valve matrix components and mechanical properties for aortic and mitral valves have been studied, very little is known about the age-related alterations that occur in the PV. In this study, we isolated PV leaflets from porcine hearts in different age groups (~ 4–6 months, denoted as young versus ~ 2 years, denoted as adult) and studied the effects of age on PV leaflet thickness, extracellular matrix components, and mechanical properties. We also conducted proteomics and RNA sequencing to investigate the global changes of PV leaflets and passage zero PV interstitial cells in their protein and gene levels. We found that the size, thickness, elastic modulus, and ultimate stress in both the radial and circumferential directions and the collagen of PV leaflets increased from young to adult age, while the ultimate strain and amount of glycosaminoglycans decreased when age increased. Young and adult PV had both similar and distinct protein and gene expression patterns that are related to their inherent physiological properties. These findings are important for us to better understand the physiological microenvironments of PV leaflet and valve cells for correctively engineering age-specific heart valve tissues.


2006 ◽  
Vol 12 (4) ◽  
pp. 831-842 ◽  
Author(s):  
Sepideh Heydarkhan-Hagvall ◽  
Maricris Esguerra ◽  
Gisela Helenius ◽  
Rigmor Söderberg ◽  
Bengt R. Johansson ◽  
...  

Soft Matter ◽  
2015 ◽  
Vol 11 (38) ◽  
pp. 7648-7655 ◽  
Author(s):  
Paul Lee ◽  
Katelyn Tran ◽  
Gan Zhou ◽  
Asheesh Bedi ◽  
Namdev B. Shelke ◽  
...  

A biphasic micro and nanostructured scaffold with hydroxyapatite and extracellular matrix components was created for the regeneration of osteochondral tissue. Material cues of the biphasic scaffold supported differentiation of bone marrow stromal cells in both osteogenic and chondrogenic lineages.


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