Transposon-facilitated recombination in classical biotypes of Vibrio cholerae

Sublett, R D; Romig, W. R.

doi:10.1128/iai.32.3.1132-1138.1981

Cited by 13 publications

(14 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, recombination analysis could not be used to order met, trp, and his relative to each other. However, the frequency of marker transfer data in Table 1 suggests that the order of the loci relative to the origin of transfer was met-trp-his, which was consistent with the map order determined by other authors for phenotypically similar markers (5,7). When Trp+ was the selected phenotype, his and tox-1000 cotransferred with trp at approximately equal frequencies.…”

supporting

confidence: 88%

Genetic Mapping of the tox-1000 Locus of Vibrio cholerae El Tor Strain RJ1

Saunders

Bramucci

1983

Infect Immun

View full text Add to dashboard Cite

show abstract

supporting

confidence: 88%

Genetic Mapping of the tox-1000 Locus of Vibrio cholerae El Tor Strain RJ1

Saunders

Bramucci

1983

Infect Immun

View full text Add to dashboard Cite

show abstract

“…cholerae. This generalized map is a summary of data obtained with strains RV79 (13, 14; Johnson, Ph.D. thesis), 569B (19,20), and 162 (32). The arrows show the polarity of transfer for some of the VcA1-facilitated donors used in this study.…”

Section: Resultsmentioning

confidence: 96%

Genetic mapping of Vibrio cholerae enterotoxin structural genes

Sporecke¹,

Castro²,

Mekalanos³

1984

J Bacteriol

View full text Add to dashboard Cite

The structural genes which constitute the cholera toxin operon, ctxAB, were genetically mapped in the Vibrio cholerae El Tor strain RV79. This strain of V. cholerae contains two copies of the ctx operon located on a 7-kilobase-pair tandemly duplicated region. We began by isolating a vibriophage VcA1 insertion mutation in one of the two ctxA genes located in this region. The mutant carrying this ctxA::VcA1 insertion, DC24, was converted to a VcA1-facilitated donor by introduction of the conjugal plasmid pSJ15, which carries an inserted copy of a defective VcA1-like prophage. The donor characteristics of DC24(pSJ15) indicated that the ctxA::VcA1 insertion mutation was near the trp region of the V. cholerae chromosome. Subsequent RV79 three-factor crosses were performed between VcA1-facilitated donors and recipient strains carrying one of two structural gene mutations in ctx, either ActxA23P Kmr or Actx-7922. The former was constructed by an in vivo marker exchange procedure and could be scored either by its kanamycin resistance phenotype or by its lack of DNA sequences homologous to the ctxA region. The Actx-7922 mutation is a total deletion of both ctx copies of strain RV79. The three-factor cross data strongly suggest that the two ctx loci of RV79 map between the nal and his genes of V. cholerae in the trp nal his linkage group. Physical analysis and heterologous crosses between an RV79 El Tor donor and a 569B classical recipient indicates that one of the two 569B ctx operon copies maps in the same region as the RV79 ctx loci (i.e., linked to nal). Together with previously published observations, these data show that the ctx structural genes are not closely linked to other genes known to affect toxin production in V. cholerae.Toxinogenic strains of Vibrio cholerae produce an extracellular heat-labile protein that is primarily responsible for the diarrheal syndrome observed in Asiatic cholera (8). Cholera toxin is now recognized as the prototype for a growing family of protein enterotoxins that produce their toxic effects via the activation of adenylate cyclase in eucaryotic cells (4,5,9). The heat-labile enterotoxin of Escherichia coli also belongs to this family, and recent DNA sequence analysis has shown the heat-labile enterotoxin genes to be 78% homologous to the cholera toxin genes (5; deWilde, Nature [London], in press). However, the LT operon eltAB appears to be exclusively located on plasmids (7, 28), while the data suggest that the cholera toxin operon ctxAB is located on the bacterial chromosome. This conclusion has been based primarily on the absence of demonstrable plasmids in toxinogenic V. cholerae strains of either the classical or El Tor biotypes (15,22).Although a variety of laboratories have isolated mutants and genetically mapped mutations that affect toxin production in the highly toxinogenic classical strain 569B, all of these mutations have turned out to be regulatory mutations (2,10,12,17,19,20). The explanation for this failure to obtain structural gene mutations in ctx in this particular ...

show abstract

“…Most early genetic studies of V. cholerae were performed with classical strains (3, 14,15). The genetic map of the classical V. cholerae strain 162 is circular, and the positions of many genetic markers on the map have been determined (14,17). Conjugal gene transfer between El Tor and classical biotypes has been demonstrated (17), and preliminary studies on the linkage map of the El Tor biotype have been done (10; J. W. Newland, B.…”

mentioning

confidence: 99%

“…In conjugal matings mediated by the wild-type P plasmid in V. cholerae, recombinants inherit donor alleles at low frequencies from all regions of the genetic map (14,15). Transposons can be introduced into both the P plasmid and the chromosome in V. cholerae to create new donor strains for transposon-facilitated recombination (Tfr) (10,17;Newland et al,in preparation). In conjugal matings, Tfr donors transfer the bacterial chromosome to recipient bacteria in an oriented and sequential manner from an origin corresponding to the site of insertion of the transposon in the donor chromosome.…”

mentioning

confidence: 99%

“…In conjugal matings, Tfr donors transfer the bacterial chromosome to recipient bacteria in an oriented and sequential manner from an origin corresponding to the site of insertion of the transposon in the donor chromosome. Isogenic Tfr donor strains with P plasmids containing the appropriate transposon in opposite orientations can, therefore, mobilize chromosomal genes in conjugal matings from a common origin but with opposite polarities (10,16,17). In the studies reported here, we used transposon-facilitated recombination mediated by transposon Tnl or transposon TnS for genetic mapping of biotype determinants of V. cholerae.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Mapping of chromosomal genes that determine the El Tor biotype in Vibrio cholerae

Green¹,

Newland²,

Holmes³

1983

Infect Immun

View full text Add to dashboard Cite

The El Tor biotype of Vibrio cholerae has several characteristics that differentiate it from the classical biotype of V. cholerae. Among these are production of soluble hemolysin(s), a cell-associated hemagglutinin for chicken erythrocytes, resistance to polymyxin B, and resistance to bacteriophages of Mukerjee group IV. In the present study, we located the determinants for hemolysin (hly), chicken erythrocyte hemagglutinin (cha), and polymyxin B resistance (pmx) on the genetic map of V. cholerae. Transposon-facilitated recombination was used to perform conjugal matings between El Tor donor strains and classical recipient strains of V. cholerae. Recombinants were selected that had inherited specific nutritional markers from the donor strains and streptomycin resistance from the recipient strains. The reconibinants were tested for the presence or absence of the unselected donor markers hly, cha, and pmx. These three El Tor biotype markers were found to be closely linked to each other and were located between the pyrA-201 and his-2 loci on the genetic map of V. cholerae.on July 31, 2020 by guest http://iai.asm.org/ Downloaded from

show abstract

Transposon-facilitated recombination in classical biotypes of Vibrio cholerae

Cited by 13 publications

References 22 publications

Genetic Mapping of the tox-1000 Locus of Vibrio cholerae El Tor Strain RJ1

Genetic Mapping of the tox-1000 Locus of Vibrio cholerae El Tor Strain RJ1

Genetic mapping of Vibrio cholerae enterotoxin structural genes

Mapping of chromosomal genes that determine the El Tor biotype in Vibrio cholerae

Contact Info

Product

Resources

About