scholarly journals Biofilm Formation by and Multicellular Behavior of Escherichia coli O55:H7, an Atypical Enteropathogenic Strain

2010 ◽  
Vol 76 (5) ◽  
pp. 1545-1554 ◽  
Author(s):  
Michal Weiss-Muszkat ◽  
Dana Shakh ◽  
Yizhou Zhou ◽  
Riky Pinto ◽  
Eddy Belausov ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
Genetic Relatedness ◽  
Liquid Interface ◽  
E Coli ◽  
Wild Type Phenotype ◽  
Enteropathogenic Strain ◽  
Biofilm Development ◽  
Air Liquid Interface ◽  
High Degree

ABSTRACT Enteropathogenic Escherichia coli (EPEC) is an important causal agent of diarrheal illness throughout the world. Nevertheless, researchers have only recently begun to explore its capacity to form biofilms. Strain O55:H7 (DMS9) is a clinical isolate belonging to the atypical EPEC (aEPEC) group, which displays a high degree of genetic relatedness to enterohemorrhagic E. coli. Strain DMS9 formed a robust biofilm on an abiotic surface at 26�C, but not at 37�C. It also formed a dense pellicle at the air-liquid interface and developed a red, rough, and dry (RDAR) morphotype on Congo red agar. Unlike a previously described E. coli O157:H7 strain, the aEPEC strain seems to express cellulose. Transposon mutagenesis was used to identify biofilm-deficient mutants. One of the mutants was inactivated in the csgFG genes, required for assembly and secretion of curli fimbriae, while a second mutant had a mutation in crl, a thermosensitive global regulator that modulates σS activity and downstream expression of curli and cellulose. The two mutants were deficient in their biofilm formation capabilities and did not form a pellicle at the air-liquid interface. Unlike in Salmonella, the csgFG mutant in aEPEC completely lost the RDAR phenotype, while the crl mutant displayed a unique RDAR “pizza”-like morphotype. Genetic complementation of the two mutants resulted in restoration of the wild-type phenotype. This report is the first to describe and analyze a multicellular behavior in aEPEC and support a major role for curli and the crl regulator in biofilm development at low temperatures corresponding to the nonmammalian host environment.

scholarly journals Autotransporters of Escherichia coli: a sequence-based characterization

Microbiology ◽  
2010 ◽  
Vol 156 (8) ◽  
pp. 2459-2469 ◽  
Author(s):  
Timothy J. Wells ◽  
Makrina Totsika ◽  
Mark A. Schembri
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
Domain Architecture ◽  
Bioinformatic Analysis ◽  
Tissue Tropism ◽  
Genome Sequences ◽  
E Coli ◽  
Disease Outcomes ◽  
High Degree ◽  
Encoding Genes

Autotransporter (AT) proteins are found in all Escherichia coli pathotypes and are often associated with virulence. In this study we took advantage of the large number of available E. coli genome sequences to perform an in-depth bioinformatic analysis of AT-encoding genes. Twenty-eight E. coli genome sequences were probed using an iterative approach, which revealed a total of 215 AT-encoding sequences that represented three major groups of distinct domain architecture: (i) serine protease AT proteins, (ii) trimeric AT adhesins and (iii) AIDA-I-type AT proteins. A number of subgroups were identified within each broad category, and most subgroups contained at least one characterized AT protein; however, seven subgroups contained no previously described proteins. The AIDA-I-type AT proteins represented the largest and most diverse group, with up to 16 subgroups identified from sequence-based comparisons. Nine of the AIDA-I-type AT protein subgroups contained at least one protein that possessed functional properties associated with aggregation and/or biofilm formation, suggesting a high degree of redundancy for this phenotype. The Ag43, YfaL/EhaC, EhaB/UpaC and UpaG subgroups were found in nearly all E. coli strains. Among the remaining subgroups, there was a tendency for AT proteins to be associated with individual E. coli pathotypes, suggesting that they contribute to tissue tropism or symptoms specific to different disease outcomes.

scholarly journals Disruption of Escherichia coli Amyloid-Integrated Biofilm Formation at the Air–Liquid Interface by a Polysorbate Surfactant

Langmuir ◽  
2013 ◽  
Vol 29 (3) ◽  
pp. 920-926 ◽  
Author(s):  
Cynthia Wu ◽  
Ji Youn Lim ◽  
Gerald G. Fuller ◽  
Lynette Cegelski
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
Liquid Interface ◽  
Air Liquid Interface

scholarly journals Biofilm Formation and Dispersal under the Influence of the Global Regulator CsrA of Escherichia coli

2002 ◽  
Vol 184 (1) ◽  
pp. 290-301 ◽  
Author(s):  
Debra W. Jackson ◽  
Kazushi Suzuki ◽  
Lawrence Oakford ◽  
Jerry W. Simecka ◽  
Mark E. Hart ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
Rna Binding ◽  
Glycogen Synthase ◽  
Regulatory Protein ◽  
Ectopic Expression ◽  
Knockout Mutant ◽  
E Coli ◽  
K 12 ◽  
Biofilm Development

ABSTRACT The predominant mode of growth of bacteria in the environment is within sessile, matrix-enclosed communities known as biofilms. Biofilms often complicate chronic and difficult-to-treat infections by protecting bacteria from the immune system, decreasing antibiotic efficacy, and dispersing planktonic cells to distant body sites. While the biology of bacterial biofilms has become a major focus of microbial research, the regulatory mechanisms of biofilm development remain poorly defined and those of dispersal are unknown. Here we establish that the RNA binding global regulatory protein CsrA (carbon storage regulator) of Escherichia coli K-12 serves as both a repressor of biofilm formation and an activator of biofilm dispersal under a variety of culture conditions. Ectopic expression of the E. coli K-12 csrA gene repressed biofilm formation by related bacterial pathogens. A csrA knockout mutation enhanced biofilm formation in E. coli strains that were defective for extracellular, surface, or regulatory factors previously implicated in biofilm formation. In contrast, this csrA mutation did not affect biofilm formation by a glgA (glycogen synthase) knockout mutant. Complementation studies with glg genes provided further genetic evidence that the effects of CsrA on biofilm formation are mediated largely through the regulation of intracellular glycogen biosynthesis and catabolism. Finally, the expression of a chromosomally encoded csrA′-′lacZ translational fusion was dynamically regulated during biofilm formation in a pattern consistent with its role as a repressor. We propose that global regulation of central carbon flux by CsrA is an extremely important feature of E. coli biofilm development.

scholarly journals Biofilm formation by South African non-O157 Shiga toxigenic Escherichia coli on stainless steel coupons

2020 ◽  
Vol 66 (4) ◽  
pp. 328-336 ◽  
Author(s):  
Emmanuel W. Bumunang ◽  
Collins N. Ateba ◽  
Kim Stanford ◽  
Tim A. McAllister ◽  
Yan D. Niu
Keyword(s):  
Escherichia Coli ◽  
Stainless Steel ◽  
South African ◽  
Food Processing ◽  
Biofilm Formation ◽  
Viable Cell ◽  
Liquid Interface ◽  
Cell Counts ◽  
Potential Source ◽  
Air Liquid Interface

This study examined the biofilm-forming ability of six non-O157 Shiga-toxin-producing Escherichia coli (STEC) strains: O116:H21, wzx-Onovel5:H19, O129:H21, O129:H23, O26:H11, and O154:H10 on stainless steel coupons after 24, 48, and 72 h of incubation at 22 °C and after 168 h at 10 °C. The results of crystal violet staining revealed that strains O129:H23 and O154:H10 were able to form biofilms on both the submerged surface and the air–liquid interface of coupons, whereas strains O116:H21, wzx-Onovel5:H19, O129:H21, and O26:H11 formed biofilm only at the air–liquid interface. Viable cell counts and scanning electron microscopy showed that biofilm formation increased (p < 0.05) over time. The biofilm-forming ability of non-O157 STEC was strongest (p < 0.05) at 22 °C after 48 h of incubation. The strongest biofilm former regardless of temperature was O129:H23. Generally, at 10 °C, weak to no biofilm was observed for isolates O154:H10, O116:H21, wzx-Onovel5:H19, O26:H11, and O129:H21 after 168 h. This study found that temperature affected the biofilm-forming ability of non-O157 STEC strains. Overall, our data indicate a high potential for biofilm formation by the isolates at 22 °C, suggesting that non-O157 STEC strains could colonize stainless steel within food-processing facilities. This could serve as a potential source of adulteration and promote the dissemination of these potential pathogens in food.

scholarly journals The pgaABCD Locus of Escherichia coli Promotes the Synthesis of a Polysaccharide Adhesin Required for Biofilm Formation

2004 ◽  
Vol 186 (9) ◽  
pp. 2724-2734 ◽  
Author(s):  
Xin Wang ◽  
James F. Preston ◽  
Tony Romeo
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
Growth Conditions ◽  
Lytic Enzymes ◽  
Surface Binding ◽  
Intact Cells ◽  
E Coli ◽  
Dependent Cell ◽  
Biofilm Dispersal ◽  
Biofilm Development

ABSTRACT Production of a polysaccharide matrix is a hallmark of bacterial biofilms, but the composition of matrix polysaccharides and their functions are not widely understood. Previous studies of the regulation of Escherichia coli biofilm formation suggested the involvement of an unknown adhesin. We now establish that the pgaABCD (formerly ycdSRQP) locus affects biofilm development by promoting abiotic surface binding and intercellular adhesion. All of the pga genes are required for optimal biofilm formation under a variety of growth conditions. A pga-dependent cell-bound polysaccharide was isolated and determined by nuclear magnetic resonance analyses to consist of unbranched β-1,6-N-acetyl-d-glucosamine, a polymer previously unknown from the gram-negative bacteria but involved in adhesion by staphylococci. The pga genes are predicted to encode envelope proteins involved in synthesis, translocation, and possibly surface docking of this polysaccharide. As predicted, if poly-β-1,6-GlcNAc (PGA) mediates cohesion, metaperiodate caused biofilm dispersal and the release of intact cells, whereas treatment with protease or other lytic enzymes had no effect. The pgaABCD operon exhibits features of a horizontally transferred locus and is present in a variety of eubacteria. Therefore, we propose that PGA serves as an adhesin that stabilizes biofilms of E. coli and other bacteria.

scholarly journals Escherichia coli and its lipopolysaccharide modulate in vitro Candida biofilm formation

2009 ◽  
Vol 58 (12) ◽  
pp. 1623-1631 ◽  
Author(s):  
H. M. H. N. Bandara ◽  
J. Y. Y. Yau ◽  
R. M. Watt ◽  
L. J. Jin ◽  
L. P. Samaranayake
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
Cell Activity ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
E Coli ◽  
Cell Numbers ◽  
Cell Counts ◽  
Biofilm Development

Demystification of microbial behaviour in mixed biofilms could have a major impact on our understanding of infectious diseases. The objectives of this study were to evaluate in vitro the interactions of six different Candida species and a Gram-negative coliform, Escherichia coli, in dual-species biofilms, and to assess the effect of E. coli LPS on Candida biofilm formation. A single isolate of E. coli ATCC 25922 and six different species of Candida, Candida albicans ATCC 90028, Candida glabrata ATCC 90030, Candida krusei ATCC 6258, Candida tropicalis ATCC 13803, Candida parapsilosis ATCC 22019 and Candida dubliniensis MYA-646, were studied using a standard biofilm assay. Each Candida species was co-cultured with E. coli on a polystyrene surface and biofilm formation was quantified by a c.f.u. assay. The biofilm was then analysed by Live/Dead staining and fluorescence microscopy (confocal laser-scanning microscopy, CLSM), whilst scanning electron microscopy (SEM) was employed to visualize the biofilm architecture. The effect of E. coli LPS on Candida biofilm cell activity at defined time intervals was assessed with an XTT reduction assay. A significant quantitative reduction in c.f.u. counts of C. tropicalis (after 90 min), C. parapsilosis (after 90 min and 24 h), C. krusei (after 24 h) and C. dubliniensis (after 24 and 48 h) was noted on incubation with E. coli in comparison with their monospecies biofilm counterparts (P <0.05). On the other hand, a simultaneous and significant reduction in E. coli cell numbers occurred on co-culture with C. albicans (after 90 min), and an elevation of E. coli cell numbers followed co-culture with C. tropicalis (after 24 h) and C. dubliniensis (after 24 h and 48 h) (P <0.05). All quantitative findings were confirmed by SEM and CLSM analyses. By SEM observation, dual-species biofilms demonstrated scanty architecture with reduced visible cell counts at all stages of biofilm development, despite profuse growth and dense colonization in their single-species counterparts. Significantly elevated metabolic activity, as assessed by XTT readings, was observed in E. coli LPS-treated C. tropicalis and C. parapsilosis biofilms (after 48 h), whilst this had the opposite effect for C. dubliniensis (after 24 h) (P <0.05). These data indicate that E. coli and Candida species in a mixed-species environment mutually modulate biofilm development, both quantitatively and qualitatively, and that E. coli LPS appears to be a key component in mediating these outcomes.

scholarly journals Evaluating the Effect of Metal Interference in Inhibition of Biofilm Formation by Uropathogenic Escherichia coli Isolated From Hospitalized Patients

2019 ◽  
Vol 3 (4) ◽  
pp. 172-177
Author(s):  
Fatemeh Khazaei ◽  
Somayeh Talebi ◽  
Farzaneh Hosseni
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
Hospitalized Patients ◽  
Pcr Analysis ◽  
Maximum Effect ◽  
Biochemical Tests ◽  
Microtiter Plate Assay ◽  
E Coli ◽  
Bivalent Metals ◽  
Biofilm Development

Introduction: Bacteria that are able to form biofilms can lead to chronic antibiotic-resistant infections and immunomodulatory effects. Iron and other bivalent metals are essential requirements for biofilm formation by bacteria. Escherichia coli is the most predominant agent causing urinary tract infection (UTI). This study aimed to assess the effects of bivalent metals (iron, zinc, cobalt, and copper) on biofilm formation by E. coli isolated from hospitalized patients suffering from UTI. Methods: A total of 110 E. coli were isolated from 200 UTI patients referred to Farmanieh hospital in Tehran, Iran. E. coli was confirmed by culture specific media, biochemical tests, and polymerase chain reaction (PCR) analysis. To determine the antibiotic resistance, the Kirby-Bauer disk method was used and the biofilm formation was assessed using microtiter plate assay and electron microscopy. Finally, the data were analyzed via paired t test using the SPSS software. Results: Based on our results, out of 110 urine samples containing E. coli, the highest and the lowest resistance were observed to ampicillin (90%) and amikacin (53%), respectively. The biofilm development was intensified in the presence of glucose and iron. The results also indicated that biofilm formation was inhibited by the use of bivalent metal ions including zinc, cobalt, and copper, with the maximum effect obtained for zinc (P < 0.05).Conclusion: Our work led us to conclude that zinc, cobalt, and copper can inhibit biofilm formation by bacterial strains in medicine.

scholarly journals Label-free quantitative proteomic analysis of the inhibition effect of Lactobacillus rhamnosus GG on Escherichia coli biofilm formation in co-culture

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Huiyi Song ◽  
Ni Lou ◽  
Jianjun Liu ◽  
Hong Xiang ◽  
Dong Shang
Keyword(s):  
Escherichia Coli ◽  
Proteomic Analysis ◽  
Biofilm Formation ◽  
Lactobacillus Rhamnosus ◽  
Differentially Expressed ◽  
Differentially Expressed Proteins ◽  
Label Free ◽  
Quantitative Proteomic Analysis ◽  
E Coli ◽  
Protein Ubiquitination

Abstract Background Escherichia coli (E. coli) is the principal pathogen that causes biofilm formation. Biofilms are associated with infectious diseases and antibiotic resistance. This study employed proteomic analysis to identify differentially expressed proteins after coculture of E. coli with Lactobacillus rhamnosus GG (LGG) microcapsules. Methods To explore the relevant protein abundance changes after E. coli and LGG coculture, label-free quantitative proteomic analysis and qRT-PCR were applied to E. coli and LGG microcapsule groups before and after coculture, respectively. Results The proteomic analysis characterised a total of 1655 proteins in E. coli K12MG1655 and 1431 proteins in the LGG. After coculture treatment, there were 262 differentially expressed proteins in E. coli and 291 in LGG. Gene ontology analysis showed that the differentially expressed proteins were mainly related to cellular metabolism, the stress response, transcription and the cell membrane. A protein interaction network and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway analysis indicated that the differentiated proteins were mainly involved in the protein ubiquitination pathway and mitochondrial dysfunction. Conclusions These findings indicated that LGG microcapsules may inhibit E. coli biofilm formation by disrupting metabolic processes, particularly in relation to energy metabolism and stimulus responses, both of which are critical for the growth of LGG. Together, these findings increase our understanding of the interactions between bacteria under coculture conditions.

scholarly journals Promiscuous Cross-seeding between Bacterial Amyloids Promotes Interspecies Biofilms

2012 ◽  
Vol 287 (42) ◽  
pp. 35092-35103 ◽  
Author(s):  
Yizhou Zhou ◽  
Daniel Smith ◽  
Bryan J. Leong ◽  
Kristoffer Brännström ◽  
Fredrik Almqvist ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Shewanella Oneidensis ◽  
Bacterial Attachment ◽  
Surface Attachment ◽  
E Coli ◽  
Amyloid Aggregates ◽  
Functional Amyloids ◽  
Biofilm Development ◽  
Distant Homolog

Amyloids are highly aggregated proteinaceous fibers historically associated with neurodegenerative conditions including Alzheimers, Parkinsons, and prion-based encephalopathies. Polymerization of amyloidogenic proteins into ordered fibers can be accelerated by preformed amyloid aggregates derived from the same protein in a process called seeding. Seeding of disease-associated amyloids and prions is highly specific and cross-seeding is usually limited or prevented. Here we describe the first study on the cross-seeding potential of bacterial functional amyloids. Curli are produced on the surface of many Gram-negative bacteria where they facilitate surface attachment and biofilm development. Curli fibers are composed of the major subunit CsgA and the nucleator CsgB, which templates CsgA into fibers. Our results showed that curli subunit homologs from Escherichia coli, Salmonella typhimurium LT2, and Citrobacter koseri were able to cross-seed in vitro. The polymerization of Escherichia coli CsgA was also accelerated by fibers derived from a distant homolog in Shewanella oneidensis that shares less than 30% identity in primary sequence. Cross-seeding of curli proteins was also observed in mixed colony biofilms with E. coli and S. typhimurium. CsgA was secreted from E. coli csgB− mutants assembled into fibers on adjacent S. typhimurium that presented CsgB on its surfaces. Similarly, CsgA was secreted by S. typhimurium csgB− mutants formed curli on CsgB-presenting E. coli. This interspecies curli assembly enhanced bacterial attachment to agar surfaces and supported pellicle biofilm formation. Collectively, this work suggests that the seeding specificity among curli homologs is relaxed and that heterogeneous curli fibers can facilitate multispecies biofilm development.

PBP4 and PBP5 are involved in regulating exopolysaccharide synthesis during Escherichia coli biofilm formation

Microbiology ◽  
2021 ◽  
Vol 167 (3) ◽  
Author(s):  
Sathi Mallick ◽  
Shanti Kiran ◽  
Tapas Kumar Maiti ◽  
Anindya S. Ghosh
Keyword(s):  
Escherichia Coli ◽  
Biofilm Formation ◽  
Type Species ◽  
Pentose Phosphate ◽  
Bacterial Cells ◽  
Surface Adhesion ◽  
Content Type ◽  
Penicillin Binding Proteins ◽  
E Coli ◽  
Link Type

Escherichia coli low-molecular-mass (LMM) Penicillin-binding proteins (PBPs) help in hydrolysing the peptidoglycan fragments from their cell wall and recycling them back into the growing peptidoglycan matrix, in addition to their reported involvement in biofilm formation. Biofilms are external slime layers of extra-polymeric substances that sessile bacterial cells secrete to form a habitable niche for themselves. Here, we hypothesize the involvement of Escherichia coli LMM PBPs in regulating the nature of exopolysaccharides (EPS) prevailing in its extra-polymeric substances during biofilm formation. Therefore, this study includes the assessment of physiological characteristics of E. coli CS109 LMM PBP deletion mutants to address biofilm formation abilities, viability and surface adhesion. Finally, EPS from parent CS109 and its ΔPBP4 and ΔPBP5 mutants were purified and analysed for sugars present. Deletions of LMM PBP reduced biofilm formation, bacterial adhesion and their viability in biofilms. Deletions also diminished EPS production by ΔPBP4 and ΔPBP5 mutants, purification of which suggested an increased overall negative charge compared with their parent. Also, EPS analyses from both mutants revealed the appearance of an unusual sugar, xylose, that was absent in CS109. Accordingly, the reason for reduced biofilm formation in LMM PBP mutants may be speculated as the subsequent production of xylitol and a hindrance in the standard flow of the pentose phosphate pathway.

Sign in / Sign up

Export Citation Format

Share Document