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K HARADA

Publications and source records attributed to K HARADA.

At least 19 recordsLinked to original sources
PubMed1964

DRUG RESISTANCE OF ENTERIC BACTERIA. 3. ACQUISITION OF TRANSFERABILITY OF NONTRANSMISSIBLE R(TC) FACTOR IN COOPERATION WITH F FACTOR AND FORMATION OF FR(TC).

Harada, Kenji (Gunma University, Maebashi, Japan), Mitsuo Kameda, Mitsue Suzuki, and Susumu Mitsuhashi. Drug resistance of enteric bacteria. III. Acquisition of transferability of nontransmissible R(TC) factor in cooperation with F factor and formation of FR(TC). J. Bacteriol. 88:1257-1265. 1964.-Transmissible drug-resistance factor R, which confers resistance to tetracycline, chloramphenicol, streptomycin, and sulfonamide, was previously found to be transduced in the system of the Salmonella E group with phage epsilon. The R factor of R(+) transductants was nontransmissible by cell-to-cell contact, and it was not eliminated by treatment with acridine dye. When R(+) transductants were infected with F factor, the nontransmissible R factor acquired transferability by conjugation. The R(+) conjugants, to which only the R factor was separately transmitted by conjugation from the (F(+)R(+)) donor, were still unable to transfer their R factor by conjugation. However, the (FR)(+) conjugants, to which both F and R factor were transmitted simultaneously by conjugation, were also capable of transferring their F and R factors by conjugation. From the present study, it was concluded that the recombinant (FR) factor was formed as a result of an interaction between F and R factors present in a host bacterium, and that one of the mechanisms of acquisition of transferability is accounted for by the formation of recombinant (FR) factor. The recombinant (FR) factor was transferable by conjugation, and it conferred both the drug-resistance and F(+) characters to the recipient cells. The (FR) factor was eliminated by treatment with acridine dye and also transduced as one unit into Escherichia coli K-12 by P1kc phage.

Acridines↗
PubMed1963

DRUG RESISTANCE OF ENTERIC BACTERIA. II. TRANSDUCTION OF TRANSMISSIBLE DRUG-RESISTANCE (R) FACTORS WITH PHAGE EPSILON.

Harada, Kenji (Gunma University, Maebashi, Japan), Mitsuo Kameda, Mitsue Suzuki, and Susumu Mitsuhashi. Drug resistance of enteric bacteria. II. Transduction of transmissible drug-resistance (R) factors with phage epsilon. J. Bacteriol. 86:1332-1338. 1963.-Transmissible drug-resistance (R) factors, which transfer resistance to tetracycline (TC), chloramphenicol, streptomycin, and sulfonamide by cell-to-cell contact, were found to be transduced in the system of Salmonella E group with phage epsilon (epsilon(15) and epsilon(34)). The R(+) transductants of S. newington (S-84) and S. chittagong (S-224) were all found to be unable to transfer their R factors by conjugation, and their R factors were not eliminated by treatment with acridine dyes so far as tested. The R factors containing TC resistance were consistently segregated when transduced. At low multiplicities of infection, the R(+) transductants with epsilon(15) were all nonlysogenic and unable to produce normal epsilon(15) phage particles; among the R(+) transductants with epsilon(34), 34% were lysogenic and 66% were sensitive to epsilon(34).

Acridines↗