scholarly journals NMR structure of the C-terminal domain of TonB protein from Pseudomonas aeruginosa

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5412 ◽  
Author(s):  
Jesper S. Oeemig ◽  
O.H. Samuli Ollila ◽  
Hideo Iwaï
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Structural Changes ◽  
Nmr Structure ◽  
Dynamics Simulation ◽  
Solution Nmr ◽  
Gram Negative Bacteria ◽  
E Coli ◽  
Terminal Domain ◽  
Tonb Protein ◽  
Monomeric Structure

The TonB protein plays an essential role in the energy transduction system to drive active transport across the outer membrane (OM) using the proton-motive force of the cytoplasmic membrane of Gram-negative bacteria. The C-terminal domain (CTD) of TonB protein is known to interact with the conserved TonB box motif of TonB-dependent OM transporters, which likely induces structural changes in the OM transporters. Several distinct conformations of differently dissected CTDs of Escherichia coli TonB have been previously reported. Here we determined the solution NMR structure of a 96-residue fragment of Pseudomonas aeruginosa TonB (PaTonB-96). The structure shows a monomeric structure with the flexible C-terminal region (residues 338–342), different from the NMR structure of E. coli TonB (EcTonB-137). The extended and flexible C-terminal residues are confirmed by 15N relaxation analysis and molecular dynamics simulation. We created models for the PaTonB-96/TonB box interaction and propose that the internal fluctuations of PaTonB-96 makes it more accessible for the interactions with the TonB box and possibly plays a role in disrupting the plug domain of the TonB-dependent OM transporters.

scholarly journals Solution NMR Structure of the Ca2+-bound N-terminal Domain of CaBP7

2012 ◽  
Vol 287 (45) ◽  
pp. 38231-38243 ◽  
Author(s):  
Hannah V. McCue ◽  
Pryank Patel ◽  
Andrew P. Herbert ◽  
Lu-Yun Lian ◽  
Robert D. Burgoyne ◽  
...  
Keyword(s):  
Nmr Structure ◽  
Solution Nmr ◽  
Terminal Domain

scholarly journals Solution NMR structure of the N-terminal domain of the human DEK protein

2008 ◽  
Vol 17 (2) ◽  
pp. 205-215 ◽  
Author(s):  
Matthew Devany ◽  
Ferdinand Kappes ◽  
Kuan-Ming Chen ◽  
David M. Markovitz ◽  
Hiroshi Matsuo
Keyword(s):  
Nmr Structure ◽  
Solution Nmr ◽  
Terminal Domain

scholarly journals National Surveillance of Antimicrobial Susceptibility of Bacteremic Gram-Negative Bacteria with Emphasis on Community-Acquired Resistant Isolates: Report from the 2019 Surveillance of Multicenter Antimicrobial Resistance in Taiwan (SMART)

2020 ◽  
Vol 64 (10) ◽  
Author(s):  
Po-Yu Liu ◽  
Yu-Lin Lee ◽  
Min-Chi Lu ◽  
Pei-Lan Shao ◽  
Po-Liang Lu ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Resistance ◽  
Klebsiella Pneumoniae ◽  
Gram Negative Bacteria ◽  
National Surveillance ◽  
Gram Negative ◽  
Content Type ◽  
E Coli ◽  
Carbapenem Resistant

ABSTRACT A multicenter collection of bacteremic isolates of Escherichia coli (n = 423), Klebsiella pneumoniae (n = 372), Pseudomonas aeruginosa (n = 300), and Acinetobacter baumannii complex (n = 199) was analyzed for susceptibility. Xpert Carba-R assay and sequencing for mcr genes were performed for carbapenem- or colistin-resistant isolates. Nineteen (67.8%) carbapenem-resistant K. pneumoniae (n = 28) and one (20%) carbapenem-resistant E. coli (n = 5) isolate harbored blaKPC (n = 17), blaOXA-48 (n = 2), and blaVIM (n = 1) genes.

scholarly journals Regulatory Conservation and Divergence of ς32 Homologs from Gram-Negative Bacteria: Serratia marcescens, Proteus mirabilis, Pseudomonas aeruginosa, and Agrobacterium tumefaciens

1998 ◽  
Vol 180 (9) ◽  
pp. 2402-2408 ◽  
Author(s):  
Kenji Nakahigashi ◽  
Hideki Yanagi ◽  
Takashi Yura
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Heat Shock ◽  
Serratia Marcescens ◽  
Proteus Mirabilis ◽  
Heat Shock Response ◽  
Gram Negative Bacteria ◽  
Heat Shock Genes ◽  
Gram Negative ◽  
E Coli ◽  
Shock Response

ABSTRACT The heat shock response in Escherichia coli is mediated primarily by the rpoH gene, encoding ς32, which is specifically required for transcription of heat shock genes. A number of ς32 homologs have recently been cloned from gram-negative bacteria that belong to the gamma or alpha subdivisions of the proteobacteria. We report here some of the regulatory features of several such homologs (RpoH) expressed in E. coli as well as in respective cognate bacteria. When expressed in an E. coli ΔrpoH strain lacking its own ς32, these homologs activated the transcription of heat shock genes (groE and dnaK) from the start sites normally used in E. coli. The level of RpoH inSerratia marcescens and Pseudomonas aeruginosacells was very low at 30°C but was elevated markedly upon a shift to 42°C, as found previously with E. coli. The increased RpoH levels upon heat shock resulted from both increased synthesis and stabilization of the normally unstable RpoH protein. In contrast, the RpoH level in Proteus mirabilis was relatively high at 30°C and increased less markedly upon heat shock, mostly by increased synthesis; this ς32 homolog was already stable at 30°C, and little further stabilization occurred upon the shift to 42°C. The increased synthesis of RpoH homologs in all these gamma proteobacteria was observed even in the presence of rifampin, suggesting that the induction occurred at the level of translation. Thus, the basic regulatory strategy of the heat shock response by enhancing the RpoH level is well conserved in the gamma proteobacteria, but some divergence in the actual mechanisms used occurred during evolution.

scholarly journals NMR structure of the N-terminal domain of E. coli DnaB helicase: implications for structure rearrangements in the helicase hexamer

Structure ◽  
1999 ◽  
Vol 7 (6) ◽  
pp. 681-690 ◽  
Author(s):  
Johan Weigelt ◽  
Susan E Brown ◽  
Caroline S Miles ◽  
Nicholas E Dixon ◽  
Gottfried Otting
Keyword(s):  
Nmr Structure ◽  
E Coli ◽  
Terminal Domain ◽  
Dnab Helicase

scholarly journals Comparison of the Effects of Gram- Negative Bacteria and Their Sterile Supernatants on Candida albicans Biofilm

2021 ◽  
Author(s):  
Mayram Hacıoğlu ◽  
Özlem Oyardı
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Candida Albicans ◽  
Inhibitory Effect ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
E Coli ◽  
Candida Albicans Biofilms ◽  
Microscopy Images ◽  
Antagonist Effect

Objective: Polymicrobial biofilms consisting of a combination of various bacteria and/or fungi are generally much more resistant than monomicrobial biofilms formed by these species alone. In this study, it was aimed to investigate how Candida albicans biofilms were affected in the presence of Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii or Pseudomonas aeruginosa or supernatants of these bacteria. Method: C. albicans with Gram-negative polymicrobial biofilms were formed on sterile microplates by using control strains of C. albicans SC 5314, E. coli ATCC 25922, K. pneumoniae ATCC 700603, A. baumannii ATCC 19606 and P. aeruginosa PA01. The number of C. albicans in biofilms was determined in the presence of both Gram- negative bacteria and sterile supernatants. Results: According to our results, all Gram negative bacteria displayed an antagonist effect against C. albicans in the biofilm and a three log decrease was observed compared to the control. Sterile supernatants were shown to have an inhibitory effect on the C. albicans biofilms and reduce the number of yeasts by at least one log. MTT assay and fluorescence microscopy images also confirmed the results. Conclusion: In C. albicans-Gram-negative polymicrobial biofilms that can occur in many infections, bacteria affected C. albicans biofilm cells as antagonist agents, both with their cells and sterile cell-free supernatants

scholarly journals Cloning and Analysis of the rnc-era-recOOperon from Pseudomonas aeruginosa

1999 ◽  
Vol 181 (16) ◽  
pp. 5111-5113 ◽  
Author(s):  
Bradford Powell ◽  
Howard K. Peters ◽  
Yoshikazu Nakamura ◽  
Donald Court
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
E Coli

ABSTRACT The rnc operon from Pseudomonas aeruginosahas been cloned and characterized. The three genes comprising this operon, rnc, era, and recO, are arranged similarly to those in some other gram-negative bacteria. Multicopy plasmids carrying the rnc operon of P. aeruginosa functionally complement mutations of thernc, era, and recO genes inEscherichia coli. In particular, the P. aeruginosa era homolog rescues the conditional lethality of eramutants in E. coli, and the presumptive protein has 60% identity with the Era of E. coli. We discuss these data and evidence suggesting that a GTPase previously purified from P. aeruginosa and designated Pra is not an Era homolog.

scholarly journals Biotinylation Facilitates the Uptake of Large Peptides by Escherichia coli and Other Gram-Negative Bacteria

2005 ◽  
Vol 71 (4) ◽  
pp. 1850-1855 ◽  
Author(s):  
Jennifer R. Walker ◽  
Elliot Altman
Keyword(s):  
Escherichia Coli ◽  
Amino Acids ◽  
Pseudomonas Aeruginosa ◽  
Gram Negative Bacteria ◽  
Cell Fractionation ◽  
Peptide Antibiotics ◽  
Small Peptides ◽  
Gram Negative ◽  
E Coli ◽  
Serovar Typhimurium

ABSTRACT Gram-negative bacteria such as Escherichia coli can normally only take up small peptides less than 650 Da, or five to six amino acids, in size. We have found that biotinylated peptides up to 31 amino acids in length can be taken up by E. coli and that uptake is dependent on the biotin transporter. Uptake could be competitively inhibited by free biotin or avidin and blocked by the protonophore carbonyl m-chlorophenylhydrazone and was abolished in E. coli mutants that lacked the biotin transporter. Biotinylated peptides could be used to supplement the growth of a biotin auxotroph, and the transported peptides were shown to be localized to the cytoplasm in cell fractionation experiments. The uptake of biotinylated peptides was also demonstrated for two other gram-negative bacteria, Salmonella enterica serovar Typhimurium and Pseudomonas aeruginosa. This finding may make it possible to create new peptide antibiotics that can be used against gram-negative pathogens. Researchers have used various moieties to cause the illicit transport of compounds in bacteria, and this study demonstrates the illicit transport of the largest known compound to date.

scholarly journals Colonization and Resistance Dynamics of Gram-Negative Bacteria in Patients during and after Hospitalization

2005 ◽  
Vol 49 (7) ◽  
pp. 2879-2886 ◽  
Author(s):  
P. Margreet G. Filius ◽  
Inge C. Gyssens ◽  
Irma M. Kershof ◽  
Patty J. E. Roovers ◽  
Alewijn Ott ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Susceptibility Testing ◽  
General Ward ◽  
Gram Negative Bacteria ◽  
Icu Patients ◽  
Gram Negative ◽  
E Coli ◽  
General Wards ◽  
Colonization Rates

ABSTRACT The colonization and resistance dynamics of aerobic gram-negative bacteria in the intestinal and oropharyngeal microfloras of patients admitted to intensive care units (ICU) and general wards were investigated during and after hospitalization. A total of 3,316 specimens were obtained from patients upon admission, once weekly during hospitalization, at discharge from the ICU, at discharge from the hospital, and 1 and 3 months after discharge from the hospital. Five colonies per specimen were selected for identification and susceptibility testing. In both patient populations, the gram-negative colonization rates in oropharyngeal specimens increased during hospitalization and did not decrease in the 3 months after discharge. In rectal specimens, colonization rates decreased during hospitalization and increased after discharge. There was a change in species distribution among the dominant microfloras during hospitalization. Klebsiella spp., Enterobacter spp., Serratia marcescens, and Pseudomonas aeruginosa were isolated more often, whereas the frequency of Escherichia coli declined. The percentage of ICU patients colonized with ampicillin- and/or cephalothin-resistant fecal E. coli was significantly increased at discharge from the hospital and did not change in the 3 months after discharge. The emergence of multidrug resistance was observed for E. coli during patient stays in the ICU. Resistance frequencies in E. coli significantly increased with the length of stay in the ICU. For the general ward population, no significant changes in resistance frequencies were found during hospitalization. From a population perspective, the risk of dissemination of resistant gram-negative bacteria into the community through hospitalized patients appears to be low for general ward patients but is noticeably higher among ICU patients.

Sign in / Sign up

Export Citation Format

Share Document