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H HASHIMOTO

Publications and source records attributed to H HASHIMOTO.

At least 19 recordsLinked to original sources
PubMed1965

DRUG RESISTANCE OF STAPHYLOCOCCI. I. TRANSDUCTION OF TETRACYCLINE RESISTANCE WITH PHAGE LYSATES OBTAINED FROM MULTIPLY RESISTANT STAPHYLOCOCCI.

Mitsuhashi, Susumu (Gunma University, Maebashi, Japan), Hiroshi Oshima, Umeko Kawaharada, and Hajime Hashimoto. Drug resistance of staphylococci. I. Transduction of tetracycline resistance with phage lysates obtained from multiply resistant staphylococci. J. Bacteriol. 89:967-976. 1965.-Tetracycline resistance was found to be transduced with phage lysates obtained from multiply resistant strains of Staphylococcus aureus of human origin. With various combinations of multiply resistant donors and tetracycline (TC)-sensitive recipients, almost all of the strains were found to be competent donors. A greater percentage of group 1 staphylococci were competent recipients. Most of the TC(+) transductants were not lysogenic for the transducing phage and were unable to transduce TC resistance with their own phage lysates obtained by ultraviolet irradiation. However, the TC(+) transductants, lysogenized with transducing phage, were capable of transducing TC resistance, and some of the lysogenizations were accompanied by changes in phage type. These results suggest that the emergence of the multiply resistant staphylococci (consistently resistant to TC) can be accounted for by transduction among various strains accompanied sometimes by changes in phage typing pattern after lysogenization, and by selection through extensive use of antibiotics and chemotherapeutic agents.

Anti-Bacterial Agents↗
PubMed1965

DRUG RESISTANCE OF STAPHYLOCOCCI. II. JOINT ELIMINATION AND JOINT TRANSDUCTION OF THE DETERMINANTS OF PENICILLINASE PRODUCTION AND RESISTANCE TO MACROLIDE ANTIBIOTICS.

Mitsuhashi, Susumu (Gunma University, Maebashi, Japan), Hajime Hashimoto, Megumi Kono, and Masato Morimura. Drug resistance of staphylococci. II. Joint elimination and joint transduction of the determinants of penicillinase production and resistance to macrolide antibiotics. J. Bacteriol. 89:988-992. 1965.-Strains of Staphylococcus aureus, which show high resistance to macrolide antibiotics (erythromycin, oleandomycin, leucomycin, and spiramycin) and the capacity to produce penicillinase, have been isolated from clinical sources. The determinants of penicillinase production (PCase(+)) and resistance to macrolide antibiotics (MAC(r)) of these strains were irreversibly eliminated by treatment with acridine or with ultraviolet light. Among the 18 strains tested, PCase(+) and MAC(r) were eliminated from all strains except one, which lost only PCase(+) but not MAC(r). The characters PCase(+) and MAC(r) were jointly transduced with the aid of phage lysates, obtained from the resistant donors by ultraviolet irradiation, into staphylococcal strains sensitive to PC and MAC. Segregation of PCase(+) and MAC(r) was rarely observed after transduction. From these results, it is suggested that the determinants of both PCase(+) and MAC(r) of staphylococci are located close together on a single genetic element, i.e., a plasmid (or episome), which exists extrachromosomally.

Anti-Bacterial Agents↗
PubMed1962

Combination of two types of transmissible drug-resistance factors in a host bacterium.

Mitsuhashi, Susumu (Gunma University, Maebashi, Japan), Kenji Harada, Hajime Hashimoto, Mitsuo Kameda, and Mitsue Suzuki. Combination of two types of transmissible drug-resistance factors in a host bacterium. J. Bacteriol. 84:9-16. 1962.-When two types of R factor, R(TC) and R (CM.SM.SA), or R(TC) and R (CM), were brought together in a host bacterium by superinfection with both factors, loss of either one or both factors was found. In the imperfectly stable existence of both factors in a host bacterium, both factors were transmitted separately by conjugation. As the result of interaction between the two types of R factor present in a host bacterium, recombinant factors were formed, R(25) (TC.CM.SM.SA) and R(31) (CM.TC). The recombinant factors were able to transfer their resistance by conjugation. They were also transduced as one unit into Escherichia coli K12 by Plke phage in the same fashion as the original R(11) (TC.CM.SM.SA) and R(14) (CM.TC) factors independently isolated from dysenteric patients.

Bacteria↗