scholarly journals Isolation and Characterization of Vibrio tubiashii Outer Membrane Proteins and Determination of a toxR Homolog

2007 ◽  
Vol 74 (3) ◽  
pp. 907-911 ◽  
Author(s):  
J. Jean-Gilles Beaubrun ◽  
M. H. Kothary ◽  
S. K. Curtis ◽  
N. C. Flores ◽  
B. E. Eribo ◽  
...  
Keyword(s):  
Membrane Proteins ◽  
Outer Membrane ◽  
Outer Membrane Proteins ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Growth Conditions ◽  
Isolation And Characterization ◽  
Vibrio Tubiashii

ABSTRACT Outer membrane proteins (OMPs) expressed by Vibrio tubiashii under different environmental growth conditions were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, N-terminal amino acid sequencing, and PCR analyses. Results showed the presence of a 38- to 40-kDa OmpU-like protein and ompU gene, a maltoporin-like protein, several novel OMPs, and a regulatory toxR homolog.

scholarly journals Identification of Polymorphic Outer Membrane Proteins of Chlamydia psittaci 6BC

2001 ◽  
Vol 69 (4) ◽  
pp. 2428-2434 ◽  
Author(s):  
Regina J. Tanzer ◽  
David Longbottom ◽  
Thomas P. Hatch
Keyword(s):  
Membrane Proteins ◽  
Outer Membrane ◽  
Disulfide Bonds ◽  
Outer Membrane Proteins ◽  
Polyacrylamide Gel Electrophoresis ◽  
Late Phase ◽  
Sodium Dodecyl ◽  
Chlamydia Psittaci ◽  
Developmental Cycle ◽  
Lauryl Sarcosine

ABSTRACT The genomes of Chlamydia spp. encode a family of putative outer membrane proteins, referred to as polymorphic outer membrane proteins (POMPs), which may play a role in the avoidance of host immune defenses. We analyzed avian strain 6BC of Chlamydia psittaci by polyacrylamide gel electrophoresis for the expression of POMPs. At least six putative POMPs were identified on the basis of their size (90 to 110 kDa) and labeling with an outer membrane-specific probe, 3-(trifluoromethyl)-3-(m-[125I]iodophenyl)diazirine. Three of the putative POMPs reacted with antiserum raised against a recombinant ovine C. psittaci strain POMP, and two possessed surface-exposed, trypsin-sensitive sites. The POMPs were dependent on disulfide bonds for their maintenance in sodium lauryl sarcosine- and sodium dodecyl sulfate-insoluble complexes but did not appear to be interpeptide disulfide bond cross-linked. The putative POMPs were found to be synthesized during the late phase of the chlamydial developmental cycle, cotemporally with the cysteine-rich doublet periplasmic proteins.

Outer membrane proteins from Serratia marcescens

1993 ◽  
Vol 39 (1) ◽  
pp. 108-111 ◽  
Author(s):  
Marta Puig ◽  
Carme Fusté ◽  
Miquel Viñas
Keyword(s):  
Membrane Proteins ◽  
Serratia Marcescens ◽  
Outer Membrane ◽  
Nutrient Availability ◽  
Sodium Dodecyl Sulphate ◽  
Gel Electrophoresis ◽  
Outer Membrane Proteins ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Cultural Conditions

The outer membrane proteins (OMPs) of several strains of Serratia marcescens have been studied by sodium dodecyl sulphate – urea – polyacrylamide gel electrophoresis. Four major OMPs, named Omp1, Omp2, Omp3, and OmpA (42, 40, 39, and 37 kDa, respectively), have been visualized. The relative proportions of Omp2 and Omp3 depend on cultural conditions (temperature of incubation, osmolarity, and nutrient availability).Key words: Serratia marcescens, outer membrane proteins, porin.

scholarly journals Establishing a Direct Role for the Bartonella bacilliformis Invasion-Associated Locus B (IalB) Protein in Human Erythrocyte Parasitism

2001 ◽  
Vol 69 (7) ◽  
pp. 4373-4381 ◽  
Author(s):  
Sherry A. Coleman ◽  
Michael F. Minnick
Keyword(s):  
Membrane Proteins ◽  
Outer Membrane ◽  
Protein Localization ◽  
Outer Membrane Proteins ◽  
Polyacrylamide Gel Electrophoresis ◽  
Buoyant Density ◽  
Sodium Dodecyl ◽  
Amino Acid Sequence Similarity ◽  
Bartonella Bacilliformis ◽  
Sds Page

ABSTRACT The invasion-associated locus A and B genes (ialAB) ofBartonella bacilliformis were previously shown to confer an erythrocyte-invasive phenotype upon Escherichia coli, indirectly implicating their role in virulence. We report the first direct demonstration of a role for ialB as a virulence factor in B. bacilliformis. The presence of a secretory signal sequence and amino acid sequence similarity to two known outer membrane proteins involved in virulence suggested that IalB was an outer membrane protein. To develop an antiserum for protein localization, the ialB gene was cloned in frame into an expression vector with a six-histidine tag and under control of thelacZ promoter. The IalB fusion protein was purified by nickel affinity chromatography and used to raise polyclonal antibodies. IalB was initially localized to the bacterial membrane fraction. To further localize IalB, B. bacilliformis inner and outer membranes were fractionated by sucrose density gradient centrifugation and identified by appearance, buoyant density (ρ), and cytochromeb content. Inner and outer membrane proteins were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and IalB was positively identified by Western blot. Contrary to expectations, IalB was localized to the inner membrane of the pathogen. To directly demonstrate a role for IalB in erythrocyte parasitism, the B. bacilliformis ialB gene was disrupted by insertional mutagenesis. The resulting ialB mutant strain was complemented in trans with a replicative plasmid encoding the full-length ialB gene. PCR and high-stringency DNA hybridization confirmed mutagenesis and transcomplementation events. Abrogation and restoration of ialB expression was verified by SDS-PAGE and immunoblotting. In vitro virulence assays showed that mutagenesis of ialB decreased bacterial association and invasion of human erythrocytes by 47 to 53% relative to controls. Transcomplementation of ialB restored erythrocyte association and invasion rates to levels observed in the parental strain. These data provide direct evidence for IalB's role in erythrocyte parasitism and represent the first demonstration of molecular Koch's postulates for a Bartonella species.

scholarly journals Isolation and characterization of outer membrane proteins (OMPs) from Salmonella Gallinarum in chicken and antibiogram of the isolates

2016 ◽  
Vol 8 (4) ◽  
pp. 2292-2297
Author(s):  
Asma Ul Husna ◽  
Shabir Ahmad Mir ◽  
Rusheeba Manzoor ◽  
Farhat Pandit ◽  
Shakil Ahmad Wani ◽  
...  
Keyword(s):  
Membrane Proteins ◽  
Outer Membrane ◽  
Antimicrobial Agents ◽  
Outer Membrane Proteins ◽  
Specific Detection ◽  
Salmonella Gallinarum ◽  
Isolation And Characterization ◽  
Faecal Samples

Salmonella isolates should be distinguished as it may assist in tracing the source of an outbreak and monitoring trends in antimicrobial resistance associated with a particular type. The specific detection of these Salmonella serotypes is therefore extremely important in order to attribute an isolate to a previously known epidemic outbreak. The present investigation was to isolate and identify S. Gallinarum, to study variation in the profile of outer membrane proteins (OMPs) and to determine in vitro antibiogram of S. Gallinarum in poultry. A total of 228 faecal samples and 22 visceral samples suspected for Salmonellosis were collected, of these 15 samples (6.0%) were found positive for S. Gallinarum. In the present study, rfbS gene sequence was helpful in the serotype-specific detection of S. Gallinarum giving a 187 bp product. Salmonella Gallinarum crude protein extracts determined by SDSPAGE showed migration of OMPs as several bands at approximate moleculer weights of appx. 45 kDa, 55 kDa, 64 kDa, 65 kDa, 74 kDa, 110 kDa, 120 kDa, 135 kDa, 150 kDa,155 kDa, 200 kDa and above 200 kDa. The study indicated a definite variation in the profile of OMPs of various Salmonella Gallinarum strains with major OMPs in the range of appx 80-100 kDa which could be the target for vaccine production. All the isolates tested against 14 antimicrobial agents showed variable susceptibility pattern with highest resistance to nalidixic acid, ampicillin and sulphadiazine and sensitivity to chloramphenicol, gentamicin and enrofloxacin.

Isolation and characterization of outer membrane proteins of Edwardsiella tarda and its application in immunoassays

Aquaculture ◽  
2007 ◽  
Vol 272 (1-4) ◽  
pp. 98-104 ◽  
Author(s):  
Gokhlesh Kumar ◽  
Gaurav Rathore ◽  
U. Sengupta ◽  
V. Singh ◽  
D. Kapoor ◽  
...  
Keyword(s):  
Membrane Proteins ◽  
Outer Membrane ◽  
Outer Membrane Proteins ◽  
Edwardsiella Tarda ◽  
Isolation And Characterization

Bacteriocin 28b fromSerratia marcescensN28b: identification ofEscherichia colisurface components involved in bacteriocin binding and translocation

1996 ◽  
Vol 42 (1) ◽  
pp. 19-26 ◽  
Author(s):  
Josefina Enfedaque ◽  
Santiago Ferrer ◽  
Joan Francesc Guasch ◽  
Miguel Regué ◽  
Joan Tomás
Keyword(s):  
Membrane Proteins ◽  
Serratia Marcescens ◽  
Outer Membrane ◽  
Outer Membrane Proteins ◽  
Binding Ability ◽  
E Coli ◽  
The Core ◽  
Isolation And Characterization ◽  
Sensitivity Tests

Serratia marcescens N28b produces bacteriocin 28b, active against Escherichia coli. Bacteriocin sensitivity tests performed on a collection of E. coli envelope mutants, and isolation and characterization of E. coli bacteriocin-28b-insensitive mutants, showed that the core lipopolysaccharide, outer membrane proteins OmpA and OmpF, and TolQ, TolA, and TolB proteins are involved in bacteriocin 28b lethal activity. These mutants were assayed for bacteriocin 28b sensitivity under normal and bypass conditions, and their bacteriocin-binding ability was determined. The results obtained suggest that the core lipopolysaccaride and outer membrane proteins OmpA and OmpF are involved in bacteriocin 28b binding. Furthermore, bacteriocin 28b translocation requires proteins TolA, TolB, and TolQ.Key words: bacteriocin, receptors, translocation, Serratia marcescens.

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