PCR cloning, sequence analysis and expression of the cybC genes encoding soluble cytochrome b-562 from Escherichia coli B strain OP7 and K strain NM522

ABSTRACT Exfoliative toxins produced by certain strains of Staphylococcus hyicus mediate exudative epidermitis in pigs. In this study the genes coding for four different exfoliative toxin from S. hyicus (ExhA, ExhB, ExhC, and ExhD) were cloned and sequenced. The coding sequence of the four toxin genes ranged from 816 to 834 bp. The amino acid sequences of these four toxins were homologous to the earlier described exfoliative toxins SHETB from S. hyicus and ETA, ETB, and ETD from Staphylococcus aureus. The homology between the S. hyicus toxins was at the same level as the homology to the exfoliative toxins from S. aureus. The toxins showed similarity to serine proteases, including preservation of the catalytic tract in ExhA, ExhB, and ExhC. However, in ExhD, Asp in the putative catalytic tract was replaced with Glu. The recombinant toxins could be expressed in Escherichia coli, and three of the four toxins were recognized by monoclonal antibodies raised against native exfoliative toxins.

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Nucleotide Sequence Analysis of the Enteropathogenic Escherichia coli Adherence Factor Plasmid pMAR7

Infection and Immunity ◽

10.1128/iai.01840-05 ◽

2006 ◽

Vol 74 (9) ◽

pp. 5408-5413 ◽

Cited By ~ 28

Author(s):

Carl Brinkley ◽

Valerie Burland ◽

Rogéria Keller ◽

Debra J. Rose ◽

Adam T. Boutin ◽

...

Keyword(s):

Escherichia Coli ◽

Sequence Analysis ◽

Nucleotide Sequence ◽

Horizontal Transfer ◽

Complete Nucleotide Sequence ◽

Nucleotide Sequence Analysis ◽

Enteropathogenic Escherichia Coli ◽

Type Iv ◽

Genes Encoding ◽

Virulence Regulator

ABSTRACT The complete nucleotide sequence was determined for pMAR7, an enteropathogenic Escherichia coli (EPEC) adherence factor (EAF) plasmid that contains genes encoding a type IV attachment pilus (Bfp) and the global virulence regulator per. Prototypic EAF plasmid pMAR7 is self-transmissible, unlike the smaller EAF plasmid pB171, which has no genes encoding conjugative functions. The tra locus, a highly conserved 33-kb segment found in pMAR7, is similar to the tra (conjugation) region of the F plasmid. ISEc13 copies flanking the pMAR7 tra region could potentially mobilize or delete the tra genes. Hybridization of 134 EPEC strains showed that a complete tra region is present only in strains of the EPEC1 clonal group. This study confirms EPEC's potential for dissemination of virulence attributes by horizontal transfer of the EAF plasmid.

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Identification and sequence analysis of Escherichia coli purE and purK genes encoding 5'-phosphoribosyl-5-amino-4-imidazole carboxylase for de novo purine biosynthesis.

Journal of Bacteriology ◽

10.1128/jb.171.1.198-204.1989 ◽

1989 ◽

Vol 171 (1) ◽

pp. 198-204 ◽

Cited By ~ 40

Author(s):

W Watanabe ◽

G Sampei ◽

A Aiba ◽

K Mizobuchi

Keyword(s):

Escherichia Coli ◽

Sequence Analysis ◽

De Novo ◽

Purine Biosynthesis ◽

De Novo Purine Biosynthesis ◽

Genes Encoding

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Sites of Adsorption of the Bacteriophages T3 and T5 on the Wall of Escherichia Coli B.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100060490 ◽

1967 ◽

Vol 25 ◽

pp. 96-97

Author(s):

Manfred E. Bayer

Keyword(s):

Escherichia Coli ◽

Cell Wall ◽

Electron Microscope ◽

Uranyl Acetate ◽

E Coli ◽

Receptor Sites ◽

Rigid Cell Wall ◽

Host Cell Surface ◽

Bacterial Viruses ◽

Escherichia Coli B

Bacterial viruses adsorb specifically to receptors on the host cell surface. Although the chemical composition of some of the cell wall receptors for bacteriophages of the T-series has been described and the number of receptor sites has been estimated to be 150 to 300 per E. coli cell, the localization of the sites on the bacterial wall has been unknown.When logarithmically growing cells of E. coli are transferred into a medium containing 20% sucrose, the cells plasmolize: the protoplast shrinks and becomes separated from the somewhat rigid cell wall. When these cells are fixed in 8% Formaldehyde, post-fixed in OsO4/uranyl acetate, embedded in Vestopal W, then cut in an ultramicrotome and observed with the electron microscope, the separation of protoplast and wall becomes clearly visible, (Fig. 1, 2). At a number of locations however, the protoplasmic membrane adheres to the wall even under the considerable pull of the shrinking protoplast. Thus numerous connecting bridges are maintained between protoplast and cell wall. Estimations of the total number of such wall/membrane associations yield a number of about 300 per cell.

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