scholarly journals Creation of a Cellooligosaccharide-Assimilating Escherichia coli Strain by Displaying Active Beta-Glucosidase on the Cell Surface via a Novel Anchor Protein

2011 ◽  
Vol 77 (17) ◽  
pp. 6265-6270 ◽  
Author(s):  
Tsutomu Tanaka ◽  
Hitomi Kawabata ◽  
Chiaki Ogino ◽  
Akihiko Kondo
Keyword(s):  
Escherichia Coli ◽  
Cell Surface ◽  
Optical Density ◽  
Coli Strain ◽  
Thermobifida Fusca ◽  
Content Type ◽  
Anchor Protein ◽  
E Coli ◽  
Beta Glucosidase

ABSTRACTWe demonstrated direct assimilation of cellooligosaccharide usingEscherichia colidisplaying beta-glucosidase (BGL). BGL fromThermobifida fuscaYX (Tfu0937) was displayed on theE. colicell surface using a novel anchor protein named Blc. This strain was grown successfully on 0.2% cellobiose, and the optical density at 600 nm (OD600) was 1.05 after 20 h.

scholarly journals Preparation of Sticky Escherichia coli through Surface Display of an Adhesive Catecholamine Moiety

2013 ◽  
Vol 80 (1) ◽  
pp. 43-53 ◽  
Author(s):  
Joseph P. Park ◽  
Min-Jung Choi ◽  
Se Hun Kim ◽  
Seung Hwan Lee ◽  
Haeshin Lee
Keyword(s):  
Escherichia Coli ◽  
Cell Surface ◽  
Communication Systems ◽  
Cell Attachment ◽  
Surface Display ◽  
Content Type ◽  
E Coli ◽  
Material Surfaces ◽  
Mussel Adhesive ◽  
Adhesive Proteins

ABSTRACTMussels attach to virtually all types of inorganic and organic surfaces in aqueous environments, and catecholamines composed of 3,4-dihydroxy-l-phenylalanine (DOPA), lysine, and histidine in mussel adhesive proteins play a key role in the robust adhesion. DOPA is an unusual catecholic amino acid, and its side chain is called catechol. In this study, we displayed the adhesive moiety of DOPA-histidine onEscherichia colisurfaces using outer membrane protein W as an anchoring motif for the first time. Localization of catecholamines on the cell surface was confirmed by Western blot and immunofluorescence microscopy. Furthermore, cell-to-cell cohesion (i.e., cellular aggregation) induced by the displayed catecholamine and synthesis of gold nanoparticles on the cell surface support functional display of adhesive catecholamines. The engineeredE. coliexhibited significant adhesion onto various material surfaces, including silica and glass microparticles, gold, titanium, silicon, poly(ethylene terephthalate), poly(urethane), and poly(dimethylsiloxane). The uniqueness of this approach utilizing the engineered stickyE. coliis that no chemistry for cell attachment are necessary, and the ability of spontaneousE. coliattachment allows one to immobilize the cells on challenging material surfaces such as synthetic polymers. Therefore, we envision that mussel-inspired catecholamine yielded stickyE. colithat can be used as a new type of engineered microbe for various emerging fields, such as whole living cell attachment on versatile material surfaces, cell-to-cell communication systems, and many others.

scholarly journals Bioinformatic and Molecular Analysis of Inverse Autotransporters from Escherichia coli

mSphere ◽  
2019 ◽  
Vol 4 (4) ◽  
Author(s):  
Kelvin G. K. Goh ◽  
Danilo G. Moriel ◽  
Steven J. Hancock ◽  
Minh-Duy Phan ◽  
Mark A. Schembri
Keyword(s):  
Escherichia Coli ◽  
Cell Surface ◽  
Biofilm Formation ◽  
Secretion System ◽  
Content Type ◽  
E Coli ◽  
Wide Range ◽  
Type V Secretion ◽  
K 12 ◽  
Type V

ABSTRACT Proteins secreted by the type V secretion system possess multiple functions, including the capacity to mediate adhesion, aggregation, and biolfilm formation. The type V secretion system can be divided into five subclasses, one of which is the type Ve system. Proteins of the type Ve secretion system are also referred to as inverse autotransporters (IATs). In this study, we performed an in silico analysis of 126 completely sequenced Escherichia coli genomes available in the NCBI database and identified several distinct IAT-encoding gene families whose distribution varied throughout the E. coli phylogeny. The genes included three characterized IATs (intimin, fdeC, and yeeJ) and four uncharacterized IATs (here named iatA, iatB, iatC, and iatD). The four iat genes were cloned from the completely sequenced environmental E. coli strain SMS-3-5 and characterized. Three of these IAT proteins (IatB, IatC, and IatD) were expressed at the cell surface and possessed the capacity to mediate biofilm formation in a recombinant E. coli K-12 strain. Further analysis of the iatB gene, which showed a unique association with extraintestinal E. coli strains, suggested that its regulation is controlled by the LeuO global regulator. Overall, this study provides new data describing the prevalence, sequence variation, domain structure, function, and regulation of IATs found in E. coli. IMPORTANCE Escherichia coli is one of the most prevalent facultative anaerobes of the human gut. E. coli normally exists as a harmless commensal but can also cause disease following the acquisition of genes that enhance its pathogenicity. Adhesion is an important first step in colonization of the host and is mediated by an array of cell surface components. In E. coli, these include a family of adhesins secreted by the type V secretion system. Here, we identified and characterized new proteins from an emerging subclass of the type V secretion system known as the inverse autotransporters (IATs). We found that IAT-encoding genes are present in a wide range of strains and showed that three novel IATs were localized on the E. coli cell surface and mediated biofilm formation. Overall, this study provides new insight into the prevalence, function, and regulation of IATs in E. coli.

scholarly journals Dynamic Mechanisms of the Bactericidal Action of an Al2O3-TiO2-Ag Granular Material on an Escherichia coli Strain

2015 ◽  
Vol 81 (20) ◽  
pp. 7135-7142 ◽  
Author(s):  
Marie-Anne Tartanson ◽  
Laurence Soussan ◽  
Matthieu Rivallin ◽  
Sophie Pecastaings ◽  
Cristian V. Chis ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Granular Material ◽  
Morphological Changes ◽  
Membrane Damage ◽  
Coli Strain ◽  
Cell Integrity ◽  
Bactericidal Action ◽  
Intact Cells ◽  
Content Type ◽  
E Coli

ABSTRACTThe bactericidal activity of an Al2O3-TiO2-Ag granular material against anEscherichia colistrain was confirmed by a culture-based method. In particular, 100% of microorganisms were permanently inactivated in 30 to 45 min. The present work aimed to investigate the mechanisms of the bactericidal action of this material and their dynamics onEscherichia coliusing different techniques. Observations by transmission electron microscopy (TEM) at different times of disinfection revealed morphological changes in the bacteria as soon as they were put in contact with the material. Notably highlighted were cell membrane damage; cytoplasm detachment; formation of vacuoles, possibly due to DNA condensation, in association with regions exhibiting different levels of electron density; and membrane lysis. PCR and flow cytometry analyses were used to confirm and quantify the observations of cell integrity. The direct exposure of cells to silver, combined with the oxidative stress induced by the reactive oxygen species (ROS) generated, was identified to be responsible for these morphological alterations. From the first 5 min of treatment with the Al2O3-TiO2-Ag material, 98% ofE. coliisolates were lysed. From 30 min, cell viability decreased to reach total inactivation, although approximately 1% of permeableE. colicells and 1% of intact cells (105genomic units · ml−1) were evidenced. This study demonstrates that the bactericidal effect of the material results from a synergic action of desorbed and supported silver. Supported silver was shown to generate the ROS evidenced.

scholarly journals Complete Annotated Genome Sequences of Two Shiga Toxin-Producing Escherichia coli Strains and One Atypical Enteropathogenic E. coli Strain, Isolated from Naturally Colonized Cattle of German Origin

2017 ◽  
Vol 5 (19) ◽  
Author(s):  
Lutz Geue ◽  
Christian Menge ◽  
Christian Berens ◽  
Stefanie A. Barth
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Coli Strain ◽  
Enteric Pathogens ◽  
Genome Sequences ◽  
Content Type ◽  
E Coli ◽  
German Origin ◽  
Cattle Herds ◽  
German Cattle

ABSTRACT Shiga toxin-producing Escherichia coli (STEC) are important zoonotic enteric pathogens with the main reservoir in cattle. Here, we present the genomes of two STEC strains and one atypical enteropathogenic E. coli strain from cattle origin, obtained during a longitudinal study in German cattle herds.

scholarly journals TleA, a Tsh-Like Autotransporter Identified in a Human Enterotoxigenic Escherichia coli Strain

2015 ◽  
Vol 83 (5) ◽  
pp. 1893-1903 ◽  
Author(s):  
Daniela Gutiérrez ◽  
Mirka Pardo ◽  
David Montero ◽  
Angel Oñate ◽  
Mauricio J. Farfán ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Genomic Library ◽  
Coli Strain ◽  
Enterotoxigenic Escherichia Coli ◽  
Watery Diarrhea ◽  
Temperature Sensitive ◽  
Content Type ◽  
E Coli ◽  
Colonization Factor ◽  
Adhesion Level

EnterotoxigenicEscherichia coli(ETEC), a leading cause of acute diarrhea, colonizes the intestine by means of adhesins. However, 15 to 50% of clinical isolates are negative for known adhesins, making it difficult to identify antigens for broad-coverage vaccines. The ETEC strain 1766a, obtained from a child with watery diarrhea in Chile, harbors the colonization factor CS23 but is negative for other known adhesins. One clone, derived from an ETEC 1766a genomic library (clone G10), did not produce CS23 yet was capable of adhering to Caco-2 cells. The goal of this study was to identify the gene responsible for this capacity. Random transposon-based mutagenesis allowed the identification of a 4,110-bp gene that codes for a homologue of the temperature-sensitive hemagglutinin (Tsh) autotransporter described in avianE. colistrains (97% identity, 90% coverage) and that is called TleA (Tsh-like ETEC autotransporter) herein. An isogenic ETEC 1766a strain with atleAmutation showed an adhesion level similar to that of the wild-type strain, suggesting that the gene does not direct attachment to Caco-2 cells. However, expression oftleAconferred the capacity for adherence to nonadherentE. coliHB101. This effect coincided with the detection of TleA on the surface of nonpermeabilized bacteria, while, conversely, ETEC 1766a seems to secrete most of the produced autotransporter to the medium. On the other hand, TleA was capable of degrading bovine submaxillary mucin and leukocyte surface glycoproteins CD45 and P-selectin glycoprotein ligand 1 (PSGL-1). These results suggest that TleA promotes colonization of the intestinal epithelium and that it may modulate the host immune response.

scholarly journals Molecular Characterization of the EhaG and UpaG Trimeric Autotransporter Proteins from Pathogenic Escherichia coli

2012 ◽  
Vol 78 (7) ◽  
pp. 2179-2189 ◽  
Author(s):  
Makrina Totsika ◽  
Timothy J. Wells ◽  
Christophe Beloin ◽  
Jaione Valle ◽  
Luke P. Allsopp ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Epithelial Cells ◽  
Cell Surface ◽  
Specific Binding ◽  
Negative Regulator ◽  
Passenger Domain ◽  
Content Type ◽  
E Coli ◽  
Ecm Proteins

ABSTRACTTrimeric autotransporter proteins (TAAs) are important virulence factors of many Gram-negative bacterial pathogens. A common feature of most TAAs is the ability to mediate adherence to eukaryotic cells or extracellular matrix (ECM) proteins via a cell surface-exposed passenger domain. Here we describe the characterization of EhaG, a TAA identified from enterohemorrhagicEscherichia coli(EHEC) O157:H7. EhaG is a positional orthologue of the recently characterized UpaG TAA from uropathogenicE. coli(UPEC). Similarly to UpaG, EhaG localized at the bacterial cell surface and promoted cell aggregation, biofilm formation, and adherence to a range of ECM proteins. However, the two orthologues display differential cellular binding: EhaG mediates specific adhesion to colorectal epithelial cells while UpaG promotes specific binding to bladder epithelial cells. The EhaG and UpaG TAAs contain extensive sequence divergence in their respective passenger domains that could account for these differences. Indeed, sequence analyses of UpaG and EhaG homologues from severalE. coligenomes revealed grouping of the proteins in clades almost exclusively represented by distinctE. colipathotypes. The expression of EhaG (in EHEC) and UpaG (in UPEC) was also investigated and shown to be significantly enhanced in anhnsisogenic mutant, suggesting that H-NS acts as a negative regulator of both TAAs. Thus, while the EhaG and UpaG TAAs contain some conserved binding and regulatory features, they also possess important differences that correlate with the distinct pathogenic lifestyles of EHEC and UPEC.

scholarly journals RegR Virulence Regulon of Rabbit-Specific Enteropathogenic Escherichia coli Strain E22

2013 ◽  
Vol 81 (4) ◽  
pp. 1078-1089 ◽  
Author(s):  
Yogitha N. Srikhanta ◽  
Dianna M. Hocking ◽  
Judyta Praszkier ◽  
Matthew J. Wakefield ◽  
Roy M. Robins-Browne ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Regulatory Protein ◽  
Bioinformatic Analysis ◽  
Coli Strain ◽  
Mobility Shift ◽  
Gene Encoding ◽  
Gene Target ◽  
Content Type ◽  
E Coli ◽  
Genes Encoding

ABSTRACTAraC-like regulators play a key role in the expression of virulence factors in enteric pathogens, such as enteropathogenicEscherichia coli(EPEC), enterotoxigenicE. coli, enteroaggregativeE. coli, andCitrobacter rodentium. Bioinformatic analysis of the genome of rabbit-specific EPEC (REPEC) strain E22 (O103:H2) revealed the presence of a gene encoding an AraC-like regulatory protein, RegR, which shares 71% identity to the global virulence regulator, RegA, ofC. rodentium. Microarray analysis demonstrated that RegR exerts 25- to 400-fold activation on transcription of several genes encoding putative virulence-associated factors, including a fimbrial operon (SEF14), a serine protease, and an autotransporter adhesin. These observations were confirmed by proteomic analysis of secreted and heat-extracted surface-associated proteins. The mechanism of RegR-mediated activation was investigated by using its most highly upregulated gene target,sefA. Transcriptional analyses and electrophoretic mobility shift assays showed that RegR activates the expression ofsefAby binding to a region upstream of thesefApromoter, thereby relieving gene silencing by the global regulatory protein H-NS. Moreover, RegR was found to contribute significantly to virulence in a rabbit infection experiment. Taken together, our findings indicate that RegR controls the expression of a series of accessory adhesins that significantly enhance the virulence of REPEC strain E22.

scholarly journals Microgravity Alters the Physiological Characteristics of Escherichia coli O157:H7 ATCC 35150, ATCC 43889, and ATCC 43895 under Different Nutrient Conditions

2014 ◽  
Vol 80 (7) ◽  
pp. 2270-2278 ◽  
Author(s):  
H. W. Kim ◽  
A. Matin ◽  
M. S. Rhee
Keyword(s):  
Escherichia Coli ◽  
Optical Density ◽  
Minimal Medium ◽  
Cultured Cells ◽  
Physiological Characteristics ◽  
Nutrient Metabolism ◽  
Content Type ◽  
E Coli ◽  
Food Borne ◽  
Space Conditions

ABSTRACTThe aim of this study is to provide understanding of microgravity effects on important food-borne bacteria,Escherichia coliO157:H7 ATCC 35150, ATCC 43889, and ATCC 43895, cultured in nutrient-rich or minimal medium. Physiological characteristics, such as growth (measured by optical density and plating), cell morphology, and pH, were monitored under low-shear modeled microgravity (LSMMG; space conditions) and normal gravity (NG; Earth conditions). In nutrient-rich medium, all strains except ATCC 35150 showed significantly higher optical density after 6 h of culture under LSMMG conditions than under NG conditions (P< 0.05). LSMMG-cultured cells were approximately 1.8 times larger than NG-cultured cells at 24 h; therefore, it was assumed that the increase in optical density was due to the size of individual cells rather than an increase in the cell population. The higher pH of the NG cultures relative to that of the LSMMG cultures suggests that nitrogen metabolism was slower in the latter. After 24 h of culturing in minimal media, LSMMG-cultured cells had an optical density 1.3 times higher than that of NG-cultured cells; thus, the higher optical density in the LSMMG cultures may be due to an increase in both cell size and number. Since bacteria actively grew under LSMMG conditions in minimal medium despite the lower pH, it is of some concern that LSMMG-culturedE. coliO157:H7 may be able to adapt well to acidic environments. These changes may be caused by changes in nutrient metabolism under LSMMG conditions, although this needs to be demonstrated in future studies.

scholarly journals Complete Genome Sequence of Escherichia coli Strain FEX669, a ColV Plasmid-Containing Isolate from Retail Chicken Meat

2021 ◽  
Vol 10 (8) ◽  
Author(s):  
Jacob R. Elder ◽  
Yanhong Liu ◽  
Siddhartha Kanrar ◽  
Andrew Gehring ◽  
Aixia Xu ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Virulence Genes ◽  
Gc Content ◽  
Genomic Analysis ◽  
Coli Strain ◽  
Content Type ◽  
E Coli ◽  
Pacbio Rs Ii ◽  
Retail Chicken Meat ◽  
Retail Food

ABSTRACT Escherichia coli strain FEX669 was isolated from retail ground chicken and shown to contain the extraintestinal pathogenic E. coli (ExPEC) virulence genes sfaD, focC, and iutA. Because this presumptive ExPEC strain was isolated from a retail food item and it was a weak biofilm former, it was characterized using whole-genome sequencing using the PacBio RS II platform. Genomic analysis showed that the FEX669 chromosome is 4,973,943 bp long, with a GC content of 50.47%, and is accompanied by a ColV plasmid that is 237,102 bp long, with a GC content of 50.49%.

scholarly journals Complete Genome Sequence of blaCTX-M-27-Encoding Escherichia coli Strain H105 of Sequence Type 131 Lineage C1/H30R

2017 ◽  
Vol 5 (31) ◽  
Author(s):  
Hiren Ghosh ◽  
Boyke Bunk ◽  
Swapnil Doijad ◽  
Judith Schmiedel ◽  
Linda Falgenhauer ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Genome Sequence ◽  
Complete Genome Sequence ◽  
Complete Genome ◽  
Coli Strain ◽  
Sequence Type ◽  
Content Type ◽  
E Coli ◽  
Extended Spectrum ◽  
Rate Of Increase

ABSTRACT Escherichia coli sequence type 131 (ST131) is the most frequent antimicrobial-resistant lineage of E. coli, propagating extended-spectrum β-lactamases (ESBL) worldwide. Recently, an alarming rate of increase in isolates of the sublineage C1/H30R-bla CTX-M-27 of ST131 in geographically distant countries was reported. Here, we present the complete genome sequence of the ST131 sublineage C1/H30R E. coli isolate harboring bla CTX-M-27 from Germany.

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