Chemistry: molecular biology and microbiology – Measuring or testing process involving enzymes or... – Involving viable micro-organism
Patent
1993-02-02
1994-09-27
Wityshyn, Michael G.
Chemistry: molecular biology and microbiology
Measuring or testing process involving enzymes or...
Involving viable micro-organism
435 18, 435 32, 435 49, 435231, 435810, 435975, 514192, 514200, C12Q 104, A61K 3143
Patent
active
053506804
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a cephalosporinase testing agent.
More specifically, the present invention relates to a cephalosporinase testing agent which enables a correct judgment as to whether or not infection-causing bacteria separated from a patient of a bacterial infectious disease are cephalosporinase-producing bacteria or not.
BACKGROUND ART
Beta-lactam antibiotics are nowadays frequently used for chemotherapy of infectious diseases. However, cephalosporin antibiotics and penicillin antibiotics, both beta-lactam antibiotics, are degraded by cephalosporinases and penicillinases, respectively, and consequently loose their antibacterial activity. For this reason, treatment by beta-lactam antibiotics can not be expected to have the desired effect as the infection-causing bacteria in a patient are beta-lactamase producing bacteria. In choosing a drug for the treatment of an infectious disease, it is thus important to judge beforehand whether or not infection-causing bacteria are beta-lactamase producing bacteria.
The detection of a beta-lactamase has been so far carried out by combined detection using a penicillinase testing agent comprising a penicillin antibiotic as a substrate together with a pH indicator as well as a cephalosporinase testing agent comprising a cephalosporin antibiotic and a pH indicator. In these testing agents, the substrate for an enzyme, i.e., a penicillin antibiotic and a cephalosporin antibiotic, is hydrolyzed to afford an acid where the bacteria tested are penicillinase producing bacteria and cephalosporinase producing bacteria, respectively, and as a result, a pH indicator contained in the testing agent will change its color. Consequently, the bacteria tested are judged to be bacteria which produce both penicillinase and cephalosporinase, where they are found as positive by each testing agent.
In general, penicillinases specifically hydrolyze penicillin antibiotics, and cephalosporinases specifically hydrolyze cephalosporin antibiotics. However, some penicillinases are known to hydrolyze not only penicillin antibiotics but also cephalosporin antibiotics as substrates. If such cephalosporinase-active penicillinase producing bacteria are subjected to the judgment according to the method described above, they will be found positive by each testing agent. As a result, bacteria producing a beta-lactamase actually classified as a penicillinase will be misjudged as bacteria producing both penicillinase and cephalosporinase. Such misjudgments sometimes lead to an improper choice of the chemotherapeutic in clinical treatment.
Accordingly, an object of the present invention is to provide a beta-lactamase testing agent which enables a proper and easy judgment of the type of beta-lactamase with no possibility of a misjudgment. In particular, its object is to provide a cephalosporinase testing agent which avoids a misjudgment on a cephalosporinase-active penicillinase that degenerates cephalosporin antibiotics. The inventors of the present invention have conducted various research, and as a result, they found that the above objects can be attained by providing a cephalosporinase testing agent which is added with a penicillinase inhibitor in addition to a cephalosporin antibiotic as a substrate for the enzyme for the detection of a cephalosporinase.
DISCLOSURE OF INVENTION
According to the present invention, there is provided a cephalosporinase testing agent comprising a cephalosporin antibiotic, a penicillinase inhibitor in an amount of 20% by weight or less based on the weight of the cephalosporin antibiotic, and a pH indicator.
The penicillinase inhibitor contained in the cephalosporinase testing agent of the present invention inhibits the activity of a penicillinase which hydrolyzes a cephalosporin antibiotic. As a consequence, bacteria producing cephalosporinase-active penicillinases are judged as cephalosporinase-negative by the cephalosporinase testing agent of the present invention. On the other hand, since a cephalosporinase can hydrolyze a cephalosporin
REFERENCES:
patent: 5026638 (1991-06-01), Saperstein
Chemical Abstracts, vol. 93, No. 7; Azuma et al.; Inhibitors of Beta-Lactamase; p. 174.
Journal of Immunological Methods; vol. 83, 1985; pp. 371-377; Premier et al.; "An Evaluation of . . . Immunoassay".
Antimicrob Agents Chemother, vol. 33, No. 3 (1989), K. Bush "Classification of .beta.-Iactamases: Groups 1, 2a, 2b, and 2b'" p. 264-270.
Chemotherapy, vol. 36, No. 3, (1990), W. Cullmann "Interaction of .beta.-Lactamase Inhibitors with Various -Lactamase Inhibitors with Various .beta.-Lactamases" pp. 200-208.
Kobayashi et al., Antimicrobial Agents and Chemotherapy, vol. 32, No. 7, pp. 1040-1045, 1988.
Labia et al., Chemical Abstracts, vol. 92, p. 199, Ref. #89743q, 1980 (Ann. Microbiol. (Paris), 1979, 130B(3), 295-304).
Cullman, Chemotherapy, vol. 36, No. 3, pp. 200-208, 1990.
Toda et al., The Journal of Antibiotics, vol. 34, No. 11, pp. 1469-1475, Nov. 1981.
Sato et al., Antimicrobial Agents and Chemotherapy, vol. 22, No. 4, pp. 579-584, Oct. 1982.
Nkazawa et al., Chemical Abstracts, vol. 106, p. 335, Ref. #116381m, 1987 (Chemotherapy (Tokyo) 1986, 34 (Suppl. 4) 1-8).
Stahl et al., Chemical Abstracts, vol. 96, p. 266, Ref. #81892z, 1982 (Ger. Offen. DE 3,019,451).
Blechschmidt et al., Chemical Abstracts, vol. 117, p. 395, Ref. #43279z, 1992 (J. Gen. Microbiol. 1992, 38(6), 1197-202).
Cordin et al., Chemical Abstracts, vol. 114, p. 451, Ref. #203396d, 1991 (J. Int. Med. Res. 1990, 18 (Suppl. 4) 670-770).
Kitzis et al., Chemical Abstracts, vol. 111, p. 424, Ref. #228866h, 1989 (Eur. J. Clin. Microbiol. Infect. Dis. 1989, 8(9) 783-788).
Inoue Matsuhisa
Sakai Akira
Mohamed Abdel A.
Showa Yakuhin Kako Co. Ltd.
Wityshyn Michael G.
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