virG, a plasmid-coded virulence gene of Shigella flexneri: identification of the virG protein and determination of the complete coding sequence.
J Bacteriol
; 171(1): 353-9, 1989 Jan.
Article
in En
| MEDLINE
| ID: mdl-2644195
ABSTRACT
On the 230-kilobase-pair (kb) virulence plasmid of Shigella flexneri 2a strain YSH6000, at least seven separate genetic determinants have been identified. One of them, an approximately 4-kb region, virG, that is required for the Sereny reaction, was extensively studied to examine the role of the virG region. The phenotype of a VirG- mutant (M94) of YSH6000 in the cytoplasm of cultured MK cells was characterized by a kinetic study of the invading shigellae. The observed phenotype of M94 in the cytoplasm indicated that the virG locus is not required for multiplication of the invading shigellae, but is essential for their spread to adjacent cells. The DNA region necessary for the VirG function was localized to a 3.6-kb DNA sequence on the 230-kb plasmid. A 130-kilodalton polypeptide was confirmed to be the virG product. External labeling of bacteria with 125I indicated that the 130-kilodalton virG protein is exposed on the bacterial surface. The nucleotide sequence of 4,472 bp, which contains the functional virG gene and its own regulatory sequence, was determined, and a large open reading frame encoding 1,102 amino acid residues was identified.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Plasmids
/
Shigella flexneri
/
Bacterial Proteins
/
Transcription Factors
/
DNA-Binding Proteins
/
Genes, Bacterial
/
Membrane Proteins
Type of study:
Diagnostic_studies
/
Prognostic_studies
Language:
En
Journal:
J Bacteriol
Year:
1989
Document type:
Article
Affiliation country:
Japan