scholarly journals Isolation and characterization of novel phage (Podoviridae ɸParuNE1) and its efficacy against multi-drug-resistant Pseudomonas aeruginosa planktonic cells and biofilm

Author(s):  
Nkechi V. Enwuru ◽  
Jason J. Gill ◽  
Katri P. Anttonen ◽  
Christian A. Enwuru ◽  
Ry. Young ◽  
...  

Abstract Background Bacterial pathogen (Pseudomonas aeruginosa) could form biofilm that conveys multi-drug resistance. Bacteriophage as an alternative to antibacterial resistance is useful against biofilm complications. This study evaluated antibacterial and biofilm removal activities of lytic phage, specific against multi-drug-resistant clinical P. aeruginosa. Results The phage showed a wide range of pH (5–10) and heat (7–44 °C) stability. Electron microscopy showed ɸPauNE1 phage head (60 nm in diameter) and non-contractile tail (12 nm in length by 8 nm in width); hence, the family Podoviridae and the order Caudovirales. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed structured protein of 55 kDa and double-stranded DNA of 45 kb. The phage was species specific and had broad host range activity. It inhibited bacterial growth at multiplicity of infection (MOI) 1–0.000001 pfu/ml. Inhibition was maximal at both low (1 × 105) and high (1 × 109) bacterial CFU/ml. Biofilm removal test showed that the phage removed more than 60% cell biomass within CFU/ml of 1.5 × 108, 6.0 × 108 and l.0 × 109. Conclusion Phage (ɸPauNE1) was unique and had broad host range activity. The phage exhibited strong bacteriolytic activity against biofilm forming multi-drug-resistant strains. It had no lytic effect on the heterogeneous strains and so a promising bioagent.

Apmis ◽  
2017 ◽  
Vol 125 (6) ◽  
pp. 579-584 ◽  
Author(s):  
Muafia Shafique ◽  
Iqbal Ahmad Alvi ◽  
Zaigham Abbas ◽  
Shafiq ur Rehman

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
M. Adamczyk ◽  
E. Lewicka ◽  
R. Szatkowska ◽  
H. Nieznanska ◽  
J. Ludwiczak ◽  
...  

Abstract Background DNA binding KfrA-type proteins of broad-host-range bacterial plasmids belonging to IncP-1 and IncU incompatibility groups are characterized by globular N-terminal head domains and long alpha-helical coiled-coil tails. They have been shown to act as transcriptional auto-regulators. Results This study was focused on two members of the growing family of KfrA-type proteins encoded by the broad-host-range plasmids, R751 of IncP-1β and RA3 of IncU groups. Comparative in vitro and in silico studies on KfrAR751 and KfrARA3 confirmed their similar biophysical properties despite low conservation of the amino acid sequences. They form a wide range of oligomeric forms in vitro and, in the presence of their cognate DNA binding sites, they polymerize into the higher order filaments visualized as “threads” by negative staining electron microscopy. The studies revealed also temperature-dependent changes in the coiled-coil segment of KfrA proteins that is involved in the stabilization of dimers required for DNA interactions. Conclusion KfrAR751 and KfrARA3 are structural homologues. We postulate that KfrA type proteins have moonlighting activity. They not only act as transcriptional auto-regulators but form cytoskeletal structures, which might facilitate plasmid DNA delivery and positioning in the cells before cell division, involving thermal energy.


1982 ◽  
Vol 152 (2) ◽  
pp. 687-691
Author(s):  
T H Watts ◽  
E A Worobec ◽  
W Paranchych

The proteins of purified inner and outer membranes obtained from Pseudomonas aeruginosa strains PAK and PAK/2Pfs were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis, transferred to nitrocellulose, and treated with antiserum raised against pure pili. Bound antipilus antibodies were visualized by reaction with 125I-labeled protein A from Staphylococcus aureus. The results showed that there are pools of pilin in both the inner and outer membranes of P. aeruginosa and that the pool size in the multipiliated strain is comparable with that of the wild-type strain.


1998 ◽  
Vol 66 (9) ◽  
pp. 4374-4381 ◽  
Author(s):  
John C. McMichael ◽  
Michael J. Fiske ◽  
Ross A. Fredenburg ◽  
Deb N. Chakravarti ◽  
Karl R. VanDerMeid ◽  
...  

ABSTRACT The UspA1 and UspA2 proteins of Moraxella catarrhalisare potential vaccine candidates for preventing disease caused by this organism. We have characterized both proteins and evaluated their vaccine potential using both in vitro and in vivo assays. Both proteins were purified from the O35E isolate by Triton X-100 extraction, followed by ion-exchange and hydroxyapatite chromatography. Analysis of the sequences of internal peptides, prepared by enzymatic and chemical cleavage of the proteins, revealed that UspA1 and UspA2 exhibited distinct structural differences but shared a common sequence including an epitope recognized by the monoclonal antibody 17C7. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), purified UspA1 exhibited a molecular weight of approximately 350,000 when unheated and a molecular weight of 100,000 after being heated for 10 min at 100°C. In contrast, purified UspA2 exhibited an apparent molecular weight of 240,000 by SDS-PAGE that did not change with the length of time of heating. Their sizes as determined by gel filtration were 1,150,000 and 830,000 for UspA1 and UspA2, respectively. Preliminary results indicate the proteins have separate functions in bacterial pathogenesis. Purified UspA1 was found to bind HEp-2 cells, and sera against UspA1, but not against UspA2, blocked binding of the O35E isolate to the HEp-2 cells. UspA1 also bound fibronectin and appears to have a role in bacterial attachment. Purified UspA2, however, did not bind fibronectin but had an affinity for vitronectin. Both proteins elicited bactericidal antibodies in mice to homologous and heterologous disease isolates. Finally, mice immunized with each of the proteins, followed by pulmonary challenge with either the homologous or a heterologous isolate, cleared the bacteria more rapidly than mock-immunized mice. These results suggest that UspA1 and UspA2 serve different virulence functions and that both are promising vaccine candidates.


1982 ◽  
Vol 152 (1) ◽  
pp. 239-245
Author(s):  
R M Berka ◽  
M L Vasil

Phospholipase C (heat-labile hemolysin) was purified from Pseudomonas aeruginosa culture supernatants to near homogeneity by ammonium sulfate precipitation followed by a novel application of DEAE-Sephacel chromatography. Enzymatic activity remained associated with DEAE-Sephacel even in the presence of 1 M NaCl, but was eluted with a linear gradient of 0 to 5% tetradecyltrimethylammonium bromide. Elution from DEAE-Sephacel was also obtained with 2% lysophosphatidylcholine, and to a lesser extent with 2% phosphorylcholine, but not at all with choline. The enzyme was highly active toward phospholipids possessing substituted ammonium groups (e.g., phosphatidycholine, lysophosphatidylcholine, and sphingomyelin); however, it had little if any activity toward phospholipids lacking substituted ammonium groups (e.g., phosphatidylethanolamine, phosphatidylserine, and phosphaditylglycerol). Collectively, these data suggest that phospholipase C from P. aeruginosa exhibits high affinity for substituted ammonium groups, but requires an additional hydrophobic moiety for optimum binding. The specific activity of the purified enzyme preparation increased 1,900-fold compared with that of culture supernatants. The molecular weight of the phospholipase C was estimated to be 78,000 by both sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Sephacryl S-200 column chromatography and was 76,000 by high-performance size exclusion chromatography. The isoelectric point was 5.5. Amino acid analysis showed that phospholipase C was rich in glycine, serine, threonine, aspartyl, glutamyl, and aromatic amino acids, but was cystine free.


1993 ◽  
Vol 39 (4) ◽  
pp. 635-640 ◽  
Author(s):  
J Risteli ◽  
I Elomaa ◽  
S Niemi ◽  
A Novamo ◽  
L Risteli

Abstract We developed a radioimmunoassay (RIA) for the carboxy-terminal telopeptides of type I collagen (ICTP), cross-linked with the helical domain of another type I collagen molecule, after isolation from human femoral bone. The cross-linked peptide was liberated by digesting insoluble, denatured bone collagen either with bacterial collagenase or with trypsin, and purified by two successive reversed-phase separations on HPLC, with monitoring of pyridinoline-specific fluorescence. The purity of the peptide was verified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and its origin in the type I collagen fibers was determined by amino-terminal amino acid sequencing. Polyclonal antibodies and a separation reagent containing second antibody and polyethylene glycol are used in the RIA. An immunologically identical, somewhat larger antigen is present in human serum; its concentration increases in multiple myeloma and in rheumatoid arthritis. The ICTP antigen seems to be cleared from the circulation by the kidneys, because glomerular filtration rates that are two-thirds of normal or less are associated with increased circulating ICTP concentrations. The CVs of the method are between 3% and 8% for a wide range of concentrations. The analysis of 40 serum samples can be completed in 4 h.


2019 ◽  
Vol 9 (2) ◽  
pp. 245 ◽  
Author(s):  
Anna Koziróg ◽  
Anna Otlewska ◽  
Magdalena Gapińska ◽  
Sylwia Michlewska

In this study, we investigated the activities of hexamethylene-1,6-bis-(N,N-dimethyl-N-dodecylammonium bromide) (C6), pentamethylene-1,5-bis-(N,N-dimethyl-N-dodecylammonium bromide) (C5), and their two neutral analogues: hexamethylene-1,6-bis-(N-methyl-N-dodecylamine) (A6) and pentamethylene-1,5-bis-(N-methyl-N-dodecylamine) (A5) at concentrations of ½ MIC, MIC, and 2 MIC (minimal inhibitory concentration) against hyphal forms of Aspergillus brasiliensis ATCC 16404. Enzymatic profiles were determined using the API-ZYM system. Extracellular proteins were extracted from the mycelia and analyzed using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The ultrastructure was evaluated using a transmission electron microscope (TEM). Both groups of surfactants caused changes in the enzyme profiles. Larger changes in the number and concentration of enzymes were noted after the action of non-ionic gemini surfactants, which may have been due to the 100× higher concentration of neutral compounds. Larger differences between the protein profiles of the control sample and the biocide samples were observed following the use of cationic compounds. On the basis of TEM analyses, we found that, with increasing concentrations of compound C6, the mycelium cells gradually degraded. After treatment at 2 MIC, only membranous structures, multiform bodies, and dense electron pellets remained. Based on these results, we concluded that cationic gemini surfactants, in comparison with their non-ionic analogues, could have a wide range of practical applications as active compounds.


2019 ◽  
Vol 5 (Supplement_1) ◽  
Author(s):  
Blanco Fernández ◽  
M E Barrios ◽  
R V Cammarata ◽  
C Torres ◽  
V A Mbayed

Abstract Bacteriophages and their endolysins, enzymes that degrade the cell walls of bacteria, are emerging as alternative tools to detect and inhibit growth of pathogen bacteria. Listeria monocytogenes is a foodborne pathogen that causes listeriosis, a serious invasive disease that affects both humans and a wide range of animals. Listeria spp. are ubiquitous in the dairy farm environment and could be present in dairy-processing plants and wastewater. All Listeria-specific bacteriophages found to date are members of the Caudovirales, of the Siphoviridae or Myoviridae families. Myophages infecting Listeria have been recently classified by the ICTV in the Spounavirinae subfamily, as well as in the P100 virus genus. The aim of this work was to isolate Listeria spp. bacteriophages and their endolysin codifying genes from wastewater of a dairy industry. Wastewater with and without treatment was sampled during the course of a year, and isolation of bacteriophages was performed after an enrichment step using as hosts L. innocua, L. ivanovii, and L. monocytogenes serotypes 1/2a, 1/2b, and 4b. Bacteriophages infecting L. innocua and L. ivanovii were isolated (n = 24) from 3 out of 12 samples. Bacteriophages were purified, and the host range was determined using spot test and EOP against five collection strains and several field isolates of Listeria spp. Two bacteriophages of narrow and broad host range, vB_Lino_VEfB7, and vB_Liva_VAfA18, were selected for further characterization. High titer stocks of bacteriophages were purified by centrifugation with ammonium acetate, and morphological information on the purified bacteriophages was obtained by negative staining and transmission electronic microscopy. Their morphology, size, and contractile tails indicated that these bacteriophages belonged to the Myoviridae family. Bacteriophage genomes were extracted using phenol-chloroform, followed by ethanol precipitation, and tested by digestion with RNAsa A and DNAse I. RFLP was performed, digesting genomes with restriction enzymes HindIII and NcoI. Consistent with the morphological findings, bacteriophages contained dsDNA genomes but showed different RFLP patterns. A PCR designed to amplify conserved domains of endolysins—PGRP and CwlA—was applied to characterize this gene. Another PCR was designed to amplify the complete endolysin gene, and the complete sequence of this gene was obtained and analyzed. Substitution model selection and a maximum likelihood phylogenetic tree of the endolysin gene was carried out using IQ-Tree software. The sequences of the endolysin gene indicated that the codified enzyme is an N-acetyl-muramoyl-L-alanine amidase, related to A511 and P100 species of the recently described P100virus genus. Further evolutionary analyses are needed to evaluate their belonging to this species or their taxonomy within this genus.


2012 ◽  
Vol 79 (2) ◽  
pp. 718-721 ◽  
Author(s):  
F. Heath Damron ◽  
Elizabeth S. McKenney ◽  
Herbert P. Schweizer ◽  
Joanna B. Goldberg

ABSTRACTWe describe a mini-Tn7-based broad-host-range expression cassette for arabinose-inducible gene expression from the PBADpromoter. This delivery vector, pTJ1, can integrate a single copy of a gene into the chromosome of Gram-negative bacteria for diverse genetic applications, of which several are discussed, usingPseudomonas aeruginosaas the model host.


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