P1 bacteriophage and tellurite sensitivity in Klebsiella pneumoniae and Escherichia coli

1984 ◽  
Vol 30 (6) ◽  
pp. 830-836 ◽  
Author(s):  
Juan Tomás ◽  
Miguel Regué ◽  
Ramón Parés ◽  
Juan Jofre ◽  
William W. Kay
Keyword(s):  
Escherichia Coli ◽  
Molecular Weight ◽  
Klebsiella Pneumoniae ◽  
Outer Membrane ◽  
Outer Membrane Proteins ◽  
Protein S ◽  
The Other ◽  
E Coli ◽  
P1 Receptor ◽  
Spontaneous Mutants

Klebsiella pneumoniae and Escherichia coli respond inversely toward P1 bacteriophage or [Formula: see text]. Klebsiella pneumoniae is resistant to both antagonists and E. coli is sensitive. However, P1 cmts lysogens (P1 cmts resistant) of K. pneumoniae became sensitive to tellurite and when cured from P1 cmts regained resistance. Escherichia coli spontaneous mutants selected for resistance to either P1 or [Formula: see text] were collaterally resistant to the other. As well, [Formula: see text] enhanced the adsorption of P1 vir to both E. coli and K. pneumoniae. Several outer membrane proteins were enhanced in the K. pneumoniae lysogens and were reduced in E. coli lysogens; one of which was the same molecular weight (77 000) in both bacteria. When partially purified it enhanced the plaque efficiency of P1 vir. Lipopolysaccharide (LPS) from E. coli C600 inactivated P1 vir, but neither the P1 lysogens nor LPS derived from the lysogens inactivated P1 vir. Escherichia coli P1 lysogens produced only heptose-deficient LPS. It is suggested that both LPS and outer membrane protein(s) comprise the P1 receptor. [Formula: see text] may interact with one or both components.

BaeR participates in cephalosporins susceptibility by regulating the expression level of outer membrane proteins in Escherichia coli

2020 ◽  
Author(s):  
Shuaiyang Wang ◽  
Chunbo You ◽  
Fareed Qumar Memon ◽  
Geyin Zhang ◽  
Yawei Sun ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Membrane Proteins ◽  
Outer Membrane ◽  
Efflux Pump ◽  
Outer Membrane Proteins ◽  
Expression Level ◽  
Antibiotics Resistance ◽  
Dilution Method ◽  
Expression Levels ◽  
E Coli

Abstract The two-component system BaeSR participates in antibiotics resistance of Escherichia coli. To know whether the outer membrane proteins involve in the antibiotics resistance mediated by BaeSR, deletion of acrB was constructed and the recombined plasmid p-baeR was introduced into E. coli K12 and K12△acrB. Minimum inhibitory concentrations (MICs) of antibacterial agents were determined by 2-fold broth micro-dilution method. Gene expressions related with major outer membrane proteins and multidrug efflux pump-related genes were determined by real-time quantitative reverse transcription polymerase chain reaction. The results revealed that the MICs of K12ΔacrB to the tested drugs except for gentamycin and amikacin decreased 2- to 16.75-folds compared with those of K12. When BaeR was overexpressed, the MICs of K12ΔacrB/p-baeR to ceftiofur and cefotaxime increased 2.5- and 2-fold, respectively, compared with their corresponding that of K12△acrB. At the same time, the expression levels of ompC, ompF, ompW, ompA and ompX showed significant reduction in K12ΔacrB/p-baeR as compared with K12△acrB. Moreover, the expression levels of ompR, marA, rob and tolC also significantly ‘decreased’ in K12ΔacrB/p-baeR. These findings indicated that BaeR overproduction can decrease cephalosporins susceptibility in acrB-free E. coli by decreasing the expression level of outer membrane proteins.

scholarly journals A Peptidomimetic Antibiotic Targets Outer Membrane Proteins and Disrupts Selectively the Outer Membrane in Escherichia coli

2015 ◽  
Vol 291 (4) ◽  
pp. 1921-1932 ◽  
Author(s):  
Matthias Urfer ◽  
Jasmina Bogdanovic ◽  
Fabio Lo Monte ◽  
Kerstin Moehle ◽  
Katja Zerbe ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Outer Membrane ◽  
Outer Membrane Proteins ◽  
Permeability Barrier ◽  
Gram Negative ◽  
Fluorescence Studies ◽  
E Coli ◽  
Interaction Sites ◽  
External Stresses ◽  
Antibiotic Discovery

Increasing antibacterial resistance presents a major challenge in antibiotic discovery. One attractive target in Gram-negative bacteria is the unique asymmetric outer membrane (OM), which acts as a permeability barrier that protects the cell from external stresses, such as the presence of antibiotics. We describe a novel β-hairpin macrocyclic peptide JB-95 with potent antimicrobial activity against Escherichia coli. This peptide exhibits no cellular lytic activity, but electron microscopy and fluorescence studies reveal an ability to selectively disrupt the OM but not the inner membrane of E. coli. The selective targeting of the OM probably occurs through interactions of JB-95 with selected β-barrel OM proteins, including BamA and LptD as shown by photolabeling experiments. Membrane proteomic studies reveal rapid depletion of many β-barrel OM proteins from JB-95-treated E. coli, consistent with induction of a membrane stress response and/or direct inhibition of the Bam folding machine. The results suggest that lethal disruption of the OM by JB-95 occurs through a novel mechanism of action at key interaction sites within clusters of β-barrel proteins in the OM. These findings open new avenues for developing antibiotics that specifically target β-barrel proteins and the integrity of the Gram-negative OM.

scholarly journals Localized adherence by enteropathogenic Escherichia coli is an inducible phenotype associated with the expression of new outer membrane proteins.

1991 ◽  
Vol 174 (5) ◽  
pp. 1167-1177 ◽  
Author(s):  
J Vuopio-Varkila ◽  
G K Schoolnik
Keyword(s):  
Escherichia Coli ◽  
Membrane Proteins ◽  
Outer Membrane ◽  
De Novo ◽  
Outer Membrane Proteins ◽  
Temporal Correlation ◽  
Enteropathogenic Escherichia Coli ◽  
E Coli

Enteropathogenic Escherichia coli grow as discrete colonies on the mucous membranes of the small intestine. A similar pattern can be demonstrated in vitro; termed localized adherence (LA), it is characterized by the presence of circumscribed clusters of bacteria attached to the surfaces of cultured epithelial cells. The LA phenotype was studied using B171, an O111:NM enteropathogenic E. coli (EPEC) strain, and HEp-2 cell monolayers. LA could be detected 30-60 min after exposure of HEp-2 cells to B171. However, bacteria transferred from infected HEp-2 cells to fresh monolayers exhibited LA within 15 min, indicating that LA is an inducible phenotype. Induction of the LA phenotype was found to be associated with de novo protein synthesis and changes in the outer membrane proteins, including the production of a new 18.5-kD polypeptide. A partial NH2-terminal amino acid sequence of this polypeptide was obtained and showed it to be identical through residue 12 to the recently described bundle-forming pilus subunit of EPEC. Expression of the 18.5-kD polypeptide required the 57-megadalton enteropathogenic E. coli adherence plasmid previously shown to be required for the LA phenotype in vitro and full virulence in vivo. This observation, the correspondence of the 18.5-kD polypeptide to an EPEC-specific pilus protein, and the temporal correlation of its expression with the development of the LA phenotype suggest that it may contribute to the EPEC colonial mode of growth.

scholarly journals Identification of a Reactivating Factor for Adenosylcobalamin-Dependent Ethanolamine Ammonia Lyase

2004 ◽  
Vol 186 (20) ◽  
pp. 6845-6854 ◽  
Author(s):  
Koichi Mori ◽  
Reiko Bando ◽  
Naoki Hieda ◽  
Tetsuo Toraya
Keyword(s):  
Escherichia Coli ◽  
Molecular Weight ◽  
Protein S ◽  
Amino Acid Residues ◽  
Permeabilized Cells ◽  
E Coli ◽  
Cell Extracts ◽  
Auxiliary Protein

ABSTRACT The holoenzyme of adenosylcobalamin-dependent ethanolamine ammonia lyase undergoes suicidal inactivation during catalysis as well as inactivation in the absence of substrate. The inactivation involves the irreversible cleavage of the Co-C bond of the coenzyme. We found that the inactivated holoenzyme undergoes rapid and continuous reactivation in the presence of ATP, Mg2+, and free adenosylcobalamin in permeabilized cells (in situ), homogenate, and cell extracts of Escherichia coli. The reactivation was observed in the permeabilized E. coli cells carrying a plasmid containing the E. coli eut operon as well. From coexpression experiments, it was demonstrated that the eutA gene, adjacent to the 5′ end of ethanolamine ammonia lyase genes (eutBC), is essential for reactivation. It encodes a polypeptide consisting of 467 amino acid residues with predicted molecular weight of 49,599. No evidence was obtained that shows the presence of the auxiliary protein(s) potentiating the reactivation or associating with EutA. It was demonstrated with purified recombinant EutA that both the suicidally inactivated and O2-inactivated holoethanolamine ammonia lyase underwent rapid reactivation in vitro by EutA in the presence of adenosylcobalamin, ATP, and Mg2+. The inactive enzyme-cyanocobalamin complex was also activated in situ and in vitro by EutA under the same conditions. Thus, it was concluded that EutA is the only component of the reactivating factor for ethanolamine ammonia lyase and that reactivation and activation occur through the exchange of modified coenzyme for free intact adenosylcobalamin.

scholarly journals Emergence of Serratia marcescens, Klebsiella pneumoniae, and Escherichia coli Isolates Possessing the Plasmid-Mediated Carbapenem-Hydrolyzing β-Lactamase KPC-2 in Intensive Care Units of a Chinese Hospital

2008 ◽  
Vol 52 (6) ◽  
pp. 2014-2018 ◽  
Author(s):  
Jia Chang Cai ◽  
Hong Wei Zhou ◽  
Rong Zhang ◽  
Gong-Xiang Chen
Keyword(s):  
Escherichia Coli ◽  
Intensive Care ◽  
Klebsiella Pneumoniae ◽  
Serratia Marcescens ◽  
Intensive Care Units ◽  
Gel Electrophoresis ◽  
Outer Membrane Proteins ◽  
Carbapenem Resistance ◽  
E Coli ◽  
Insertional Inactivation

ABSTRACT Twenty-one Serratia marcescens, ten Klebsiella pneumoniae, and one Escherichia coli isolate with carbapenem resistance or reduced carbapenem susceptibility were recovered from intensive care units (ICUs) in our hospital. Enterobacterial repetitive intergenic consensus-PCR and pulsed-field gel electrophoresis demonstrated that all the S. marcescens isolates belonged to a clonal strain and the 10 K. pneumoniae isolates were indistinguishable or closely related to each other. The MICs of imipenem, meropenem, and ertapenem for all isolates were 2 to 8 μg/ml, except for K. pneumoniae K10 (MICs of 128, 256, and >256 μg/ml). Isoelectric focusing, PCRs, and DNA sequencing indicated that all S. marcescens isolates produced KPC-2 and a β-lactamase with a pI of 6.5. All K. pneumoniae isolates produced TEM-1, KPC-2, CTX-M-14, and a β-lactamase with a pI of 7.3. The E. coli E1 isolate produced KPC-2, CTX-M-15, and a β-lactamase with a pI of 7.3. Conjugation studies with E. coli (EC600) resulted in the transfer of reduced carbapenem susceptibility compared to that of the original isolates, and only the bla KPC-2 gene was detected in E. coli transconjugants. Plasmid restriction analysis showed identical restriction patterns among all E. coli transconjugants. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and ompK35/36 gene sequence analysis of outer membrane proteins revealed that K. pneumoniae K10 failed to express OmpK36, because of insertional inactivation by an insertion sequence ISEcp1. All these results indicate that KPC-2-producing S. marcescens, K. pneumoniae, and E. coli isolates emerged in ICUs in our hospital. KPC-2 combined with porin deficiency results in high-level carbapenem resistance in K. pneumoniae. The same bla KPC-2-encoding plasmid was spread among the three different genera.

scholarly journals Ceftazidime-Resistant Klebsiella pneumoniae and Escherichia coli Isolates Producing TEM-10 and TEM-43 β-Lactamases from St. Louis, Missouri

1998 ◽  
Vol 42 (7) ◽  
pp. 1671-1676 ◽  
Author(s):  
Youjun Yang ◽  
Niraja Bhachech ◽  
Patricia A. Bradford ◽  
Bradley D. Jett ◽  
Daniel F. Sahm ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Klebsiella Pneumoniae ◽  
Hydrolytic Activity ◽  
Pulsed Field Gel Electrophoresis ◽  
The Other ◽  
Hydrolysis Rate ◽  
Cloning And Sequencing ◽  
E Coli ◽  
Jewish Hospital ◽  
Encoding Genes

ABSTRACT Ceftazidime-resistant Escherichia coli andKlebsiella pneumoniae (49 and 102 isolates, respectively) were collected from Barnes-Jewish Hospital, St. Louis, Mo., from 1992 to 1996. They were uniformly resistant to ceftazidime, generally resistant to aztreonam, and variably susceptible to cefotaxime. Four representative E. coli strains and 15Klebsiella strains were examined. From one to four β-lactamases were produced per strain, with three possible enzymes related to ceftazidime resistance: enzymes with pI values of 5.6, 6.1, or 7.6. By pulsed-field gel electrophoresis there were at least 13 different Klebsiella strain types and 3 different E. coli strain types, indicating that the outbreak was not clonal. After cloning and sequencing of the β-lactamase-encoding genes, the enzyme with a pI of 5.6 was identified as TEM-10. The enzyme with a pI of 6.1 was a novel TEM variant (TEM-43) with Lys at 104, His at 164, and Thr at 182. TEM-43 showed broad-spectrum hydrolytic activity against all penicillins, with the highest hydrolysis rate for ceftazidime compared to those for the other expanded-spectrum cephalosporins. Aztreonam was also a good substrate for TEM-43, with hydrolytic activity similar to that of ceftazidime and affinity higher than that of ceftazidime. The TEM-43 β-lactamase was well inhibited by clavulanic acid and tazobactam at concentrations of <10 nM. Sulbactam was less effective than the other inhibitors. The Thr182 mutation previously reported in an inhibitor-resistant β-lactamase did not cause the TEM-43 enzyme to become resistant to any of the inhibitors.

e-Membranome: a Database for Genome-Wide Analysis of Escherichia coli Outer Membrane Proteins

2020 ◽  
Vol 21 ◽  
Author(s):  
Kang Mo Lee ◽  
Seung-Hak Cho ◽  
Cheorl-Ho Kim ◽  
Jong Hyun Kim ◽  
Sung Soon Kim
Keyword(s):  
Escherichia Coli ◽  
Membrane Proteins ◽  
Outer Membrane ◽  
Outer Membrane Proteins ◽  
3D Structure ◽  
Glycan Array ◽  
Epitope Region ◽  
E Coli ◽  
Genome Wide ◽  
A Genome

Objectives: Lectin-like adhesins of enteric bacterial pathogens such as Escherichia coli are an attractive target for vaccine or drug development. Here, we have developed e-Membranome as a database of genome-wide putative adhesins in Escherichia coli (E. coli). Methods: The outer membrane adhesins were predicted from the annotated genes of Escherichia coli strains using the PSORTb program. Further analysis was performed using Interproscan and the String database. The candidate proteins can be investigated for homology modeling of the three-dimensional (3D) structure (I-TASSER version 5.1), epitope region (ABCpred), and the glycan array. Results: e-Membranome is implemented using the Django (version 2.2.5) framework. The Web Application Server Apache Tomcat 6.0 is integrated in the platform on Ubuntu Linux (version 16.04). MySQL database (version 5.7) is used as a database engine. The information of homology model of the 3D structure, epitope region, and affinity information from the glycan array will be stored in the e-Membranome database. As a case study, we performed a genome-wide screening of outer membrane-embedded proteins from the annotated genes of E. coli using the e-Membranome pipeline. Conclusion: This platform is expected to be a valuable resource for advancing research of outer membrane proteins for the construction of lectin-glycan interaction network of E. coli. In addition, the e-Membranome pipeline can be extended to other similar biological systems that need to address host-pathogen interactions.

scholarly journals Analysis of colostrum IgA against bacteria involved in neonatal infections

2017 ◽  
Vol 15 (3) ◽  
pp. 256-261 ◽  
Author(s):  
Elizabeth Moreira Dias ◽  
Denise Bertulucci Rocha Rodrigues ◽  
Vinícius Rangel Geraldo-Martins ◽  
Ruchele Dias Nogueira
Keyword(s):  
Escherichia Coli ◽  
Molecular Weight ◽  
Staphylococcus Aureus ◽  
Klebsiella Pneumoniae ◽  
Salmonella Enteritidis ◽  
Clinical Evidence ◽  
Immune Protection ◽  
Neonatal Infections ◽  
E Coli ◽  
Iga Antibodies

ABSTRACT Objective To describe e compare the specificity of IgA antibodies against bacteria extract of Klebsiella pneumoniae , Staphylococcus aureus , Escherichia coli , and Salmonella enteritidis . Methods Colostrum samples were aseptically collected in the first 12 hours after C-section delivery. The specificity of IgA against bacteria extracts was analyzed by the Western blot. Results The findings showed proteins of high molecular weight frequently detectable in the samples. S. aureus was the most frequently found bacterium in the samples (p<0.05). Approximately 93.8, 56.3, 62.5 and 60.4% of samples presented IgA reactive to S. aureus , K. pneumoniae , S. enteritidis, and E. coli, respectively. Roughly 40% of samples showed no IgA reactive to K. pneumoniae, S. enteritidis and E. coli . Conclusion Clinical evidence of the importance of breastfeeding for the immune protection of neonates was consistent with the observed immunological findings, since most samples showed IgA reactive against the species tested. The application and development of immunotherapies during pregnancy, focused on frequently detected antigens, could be an important tool to enhance the presence of IgA in colostrum.

scholarly journals Helical Disposition of Proteins and Lipopolysaccharide in the Outer Membrane of Escherichia coli

2005 ◽  
Vol 187 (6) ◽  
pp. 1913-1922 ◽  
Author(s):  
Anindya S. Ghosh ◽  
Kevin D. Young
Keyword(s):  
Escherichia Coli ◽  
Membrane Proteins ◽  
Outer Membrane ◽  
Fluorescent Dyes ◽  
Cell Envelope ◽  
Outer Membrane Proteins ◽  
E Coli ◽  
Physiological Processes ◽  
Side Walls

ABSTRACT In bacteria, several physiological processes once thought to be the products of uniformly dispersed reactions are now known to be highly asymmetric, with some exhibiting interesting geometric localizations. In particular, the cell envelope of Escherichia coli displays a form of subcellular differentiation in which peptidoglycan and outer membrane proteins at the cell poles remain stable for generations while material in the lateral walls is diluted by growth and turnover. To determine if material in the side walls was organized in any way, we labeled outer membrane proteins with succinimidyl ester-linked fluorescent dyes and then grew the stained cells in the absence of dye. Labeled proteins were not evenly dispersed in the envelope but instead appeared as helical ribbons that wrapped around the outside of the cell. By staining the O8 surface antigen of E. coli 2443 with a fluorescent derivative of concanavalin A, we observed a similar helical organization for the lipopolysaccharide (LPS) component of the outer membrane. Fluorescence recovery after photobleaching indicated that some of the outer membrane proteins remained freely diffusible in the side walls and could also diffuse into polar domains. On the other hand, the LPS O antigen was virtually immobile. Thus, the outer membrane of E. coli has a defined in vivo organization in which a subfraction of proteins and LPS are embedded in stable domains at the poles and along one or more helical ribbons that span the length of this gram-negative rod.

scholarly journals Effects of Multiple Deletions of Murein Hydrolases on Viability, Septum Cleavage, and Sensitivity to Large Toxic Molecules in Escherichia coli

2002 ◽  
Vol 184 (22) ◽  
pp. 6093-6099 ◽  
Author(s):  
Christoph Heidrich ◽  
Astrid Ursinus ◽  
Jürgen Berger ◽  
Heinz Schwarz ◽  
Joachim-Volker Höltje
Keyword(s):  
Escherichia Coli ◽  
Molecular Weight ◽  
Membrane Permeability ◽  
Outer Membrane ◽  
High Molecular Weight ◽  
Macconkey Agar ◽  
Lytic Transglycosylases ◽  
E Coli ◽  
Murein Hydrolase ◽  
Outer Membrane Permeability

ABSTRACT The multiplicity of murein hydrolases found in most bacteria presents an obstacle to demonstrating the necessity of these potentially autolytic enzymes. Therefore, Escherichia coli mutants with deletions in multiple murein hydrolases, including lytic transglycosylases, amidases, and dd-endopeptidases, were constructed. Even a mutant from which seven different hydrolases were deleted was viable and grew at a normal rate. However, penicillin-induced lysis was retarded. Most of the mutants were affected in septum cleavage, which resulted in the formation of chains of cells. All three enzymes were shown to be capable of splitting the septum. Failure to cleave the septum resulted in an increase in outer membrane permeability, and thus the murein hydrolase mutants did not grow on MacConkey agar plates. In addition, the hydrolase mutants not only could be lysed by lysozyme in the absence of EDTA but also were sensitive to high-molecular-weight antibiotics, such as vancomycin and bacitracin, which are normally ineffective against E. coli.

Sign in / Sign up

Export Citation Format

Share Document