Summary
Acquired resistance can be defined as a qualitative alteration of the genetic material of a cell which is phenotypically correlated with a measurable decrease of the cell's sensitivity against one or several chemotherapeutic agents. There are two basic genetic mechanisms which can lead to the emergence of resistance: mutation and the acquisition of additional genetic material from another cell. Both forms of resistance play an important role in clinical situations: the emergence of resistance by mutation occurs in tumor cells and can also lead to therapeutic problems in antimicrobial chemotherapy. In bacteria, however, acquisition of resistance plasmids represents the dominating mechanism which is responsible for most therapeutic problems in the clinical environment. The different genetic mechanisms involved in the emergence of resistance are paralleled — at least in bacteria — by two principally different groups of biochemical mechanisms implementing resistance. Mutations lead to alterations of single cell constituents such as the cell membrane or cellular receptors necessary for the binding of the antimicrobial agent. This form of resistance is biochemically characterized by the inaccessibility of the cell interior for a particular compound or by the modification of an intracellular binding site which loses its affinity for the chemotherapeutic agent. Resistance plasmids on the other hand code for enzymes which inactivate the antibiotic (β-lactamases, aminoglycoside-inactivating enzymes, chloramphenicol-acetyltransferase). In some cases, they direct the synthesis of proteins which affect cell permeability (tetracycline) or isoenzymes which have a lower affinity for the inhibitor (trimethoprim). Resistance against antibiotics can be inducible. In these cases the regulatory mechanisms involved are stable genetical traits as resistance itself. Using chloramphenicol, β-lactam-antibiotics and aminoglycosides as examples, it is demonstrated that resistance data gathered early in the development of a new drug are of little value in estimating the clinical potential of a new compound. Information on the rate at which resistance develops, on the pattern according to which it emerges (“single step” or “multi step”) and on cross-resistance patterns is important in the characterization of a new drug but is often invalidated by later findings obtained in the clinical environment. The problem appears somewhat simpler if a new drug is a member of an already known class of compounds, e.g. a β-lactam or an aminoglycoside. In such cases our knowledge of frequent enzymatic inactivation mechanisms provides a basis not only for the evaluation of an existing drug, but also for the synthesis of new derivatives.
Zusammenfassung
Das Problem der Resistenz von Mikroorganismen gegen antiparasitäre Wirkstoffe ist etwa so alt wie die Chemotherapie selbst. Erworbene Resistenz wurde jedoch erst in den Jahren von 1945 bis 1955 als das Ergebnis eines nicht gerichteten genetischen Prozesses erkannt. Bakterien können Resistenz gegen antimikrobielle Wirkstoffe auf zwei grundsätzlich verschiedenen Wegen erwerben: einmal durch Mutation, das heißt, durch eine qualitativ definierbare Änderung des in der Zelle vorhandenen genetischen Materials und zweitens durch den Hinzugewinn neuer genetischer Information von außen. Beide Formen der Resistenz haben in klinischen Situationen Bedeutung: Resistenzentstehung durch Mutation spielt eine wichtige Rolle in der Onkologie und ist zuweilen auch Ursache von klinisch beobachteten Resistenzen in der antimikrobiellen Chemotherapie. Für den Bereich der antibakteriellen Chemotherapie ist allerdings die Übertragung und der Besitz von Resistenzplasmiden der epidemiologisch wichtigere Mechanismus der Resistenzentstehung. Den verschiedenen genetischen Mechanismen, die zur Ausbildung von Resistenz gegen Chemotherapeutika führen können, entsprechen — zumindest in Bakterien — auch zwei grundsätzlich voneinander verschiedene biochemische Mechanismen. Mutationen führen zu Veränderungen einzelner Zellbestandteile, die dazu führen, daß ein Wirkstoff nicht mehr in das Zellinnere gelangt oder daß ein Rezeptor, mit dem der Wirkstoff vorher reagieren konnte, diesen nicht mehr mit der vorher gezeigten Affinität bindet. Hingegen codieren Resistenzplasmide für Proteine, die bis dahin in der Zelle nicht vorhanden waren. Hier handelt es sich meistens um Enzyme, die Antibiotika inaktivieren können (β-Lactamasen, Aminoglycosidinaktivierende Enzyme) oder um Proteine, die die Zellpermeabilität beeinflussen, gelegentlich aber auch um neue Enzyme, die es der Zelle ermöglichen, einen biosynthetischen Block zu umgehen (Beispiel: Trimethoprim). Häufig sind Antibiotikainaktivierende Enzyme induzierbar: sie werden dann nicht ständig synthetisiert, sondern nur in Gegenwart des zu inaktivierenden Antibiotikums. Der regulatorische Mechanismus, der die An-und Abschaltung derartiger Enzymsynthesen ermöglicht, ist ebenso ein vererbbares genetisches Merkmal wie die Resistenz selbst. Im letzten Abschnitt der Arbeit wird auf die Bedeutung von Resistenzparametern für die Beurteilung neuer Chemotherapeutika eingegangen. An den Beispielen Chloramphenicol, β-Lactam-Antibiotika und Aminoglycoside wird gezeigt, daß frühe auf Laborexperimenten beruhende Aussagen über die Schnelligkeit und den Typ der Resistenzentstehung („single step“ oder „multi step“) sowie über Kreuzresistenzmuster meist nicht den später in der Klinik angetroffenen Verhältnissen entsprechen. Obwohl solche Laboratoriumsdaten zur Charakterisierung einer neuen Verbindung gehören, sind sie zur Beurteilung des klinischen Wertes einer neuen Verbindung kaum brauchbar. Ob Resistenzparameter die Verwendung eines Chemotherapeutikums in der Klinik einschränken können und welche Mechanismen dabei epidemiologisch dominieren, läßt sich meist erst nach längerer klinischer Anwendung eines neuen Wirkstoffes beurteilen. Etwas einfacher liegen die Verhältnisse allerdings, wenn es sich bei einem neuen Wirkstoff um einen Vertreter einer bereits bekannten und klinisch breit eingesetzten Substanzgruppe handelt, etwa um ein β-Lactam oder um Aminoglycoside. In diesem Zusammenhang wird auf bekannte, epidemiologisch wichtige Inaktivierungsmechanismen hingewiesen und auf chemische Manipulationen, die geeignet sind, solchen Mechanismen auszuweichen.
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Literature
Ehrlich, P. Die Grundlagen der experimentellen Chemotherapie. Z. angew. Chem. 23 (1910) 2–8.
Ehrlich, P. Chemotherapeutics: scientific principles, methods and results. Lancet (1913/14) 445–451.
Lamarck, J. B., de Monet, P.: Philosophie Zoologique. Paris 1809.
Hinshelwood, C. N. The chemical kinetics of the bacterial cell. Oxford University Press, London 1946.
Luria, S. E., Delbrück, M. Mutations in bacteria from virus sensitivity to virus resistance. Genetics 28 (1943) 491–511.
Newcombe, H. B. Origin of bacterial variants. Nature 164 (1949) 150–151.
Lederberg, J., Lederberg, E. M. Replica plating and indirect selection of bacterial mutants. J. Bact.63 (1952) 399–406.
Lederberg, J., Tatum, E. M. Gene recombination in E. coli. Nature 158 (1946) 558–559.
Demerec, M. Genetic aspects of drug resistance. In: Drug resistance in microorganisms, Ciba Foundation Symposium, p. 47–58. Little, Brown, Boston 1957.
Adam, D. Interaction of antibiotics with host factors. In: Nonspecific factors influencing host resistance (Ed.:W. Braun, J. Ungar), pp. 457–458. Karger, Basel 1973.
Funatsu, G., Wittmann, H. G. Location of amino acid replacements in protein S 12 isolated from E. coli mutants resistant to streptomycin. J. molec. Biol. 68 (1972) 547–550.
Davies, J., Nomura, M. The genetics of bacterial ribosomes. Ann. Rev. Gen. 6 (1972) 203–234.
Pitton, J. S. Mechanisms of bacterial resistance to antibiotics. Ergebn. Physiol. 65 (1972) 17–93.
Beneviste, R., Davies, J. Mechanisms of antibiotic resistance in bacteria. Ann. Rev. Biochem. 42 (1973) 471–506.
Bockrash, R. C., Carlson, K., Bender, P. An unsuccessful search for amber streptomycin resistant or dependent mutants in E. coli. Microbiol. gen. Bull.31 (1969) 12–13.
Anderson, E. S. The ecological significance of R-factor activity. In: Topics in infections diseases (Ed.:Drews, J., Hahn, F. E.), pp. 59–76. Springer, Wien-New York 1975.
Clowes, R. C. Molecular structure of bacterial plasmids. Bact. Rev. 36 (1972) 361–405.
Mitsuhashi, S., Iyobe, S., Inoue, M. Genetic of R-factors. Antibiot. et Chemother. 20 (1976) 133–174.
Levy, S. B., McMurray, L. Detection of an inducible membrane protein associated with R-factor-mediated tetracycline resistance. Biochem. biophys. Res. Commun. 56 (1974) 1060–1068.
Franklin, T. J., Foster, S. J. Effect of osmotic shock on tetracycline resistance in E. coli bearing an R-factor. Biochem. J. 121 (1971) 287–292.
Fleming, M. P., Datta, N., Grüneberg, R. N. Trimethoprim resistance determined by R-factors. Brit. med. J. (1972/1) 726–728.
Datta, N., Hedges, R. W. Trimethoprim resistance conferred by W plasmids in enterobacteriaceae. J. gen. Microbiol. 72 (1972) 349–355.
Amyes, S. G., Smith, J. T. R-factor trimethroprim resistance mechanism: an insusceptible target site. Biochem. biophys. Res. Commun. 58 (1974) 412–418.
Anderson, E. S. The ecology of transferable drug resistance in the enterobacteria. Ann. Rev. Microbiol. 22 (1968) 131–180.
Anderson, E. S., Natkin, E. Transduction of resistance determinants and R-factors of the Δ transfer system by phage Plkc. Mol. gen. Genet. 114 (1972) 261–265.
Rutman, R. J., Chun, E. H. L., Lewis, F. S. Permeability difference as a source of resistance to alkylating agents in Ehrlich tumor cells. Biochem. biophys. Res. Commun. 32 (1968) 650–657.
Goldstein, M. N., Hamm, K., Amrod, E. Incorporation of tritiated actinomycin D into drug-sensitive and drug-resistant HeLa cells. Science 151 (1966) 1155–1156.
Pato, M. L., Brown, G. M. Mechanisms of resistance in E. coli to sulfonamide. Arch. biochem. Biophys. 103 (1963) 443–448.
Bertino, J. R., Hryniuk, W. M., Capizzi, R. In: Prediction or response in cancer chemotherapy. (Ed.:Hall, T. C.), p. 170. US Government Printing Office, Washington, D.C. 1971.
Tanaka, K., Teraoka, H., Tamaki, M., Takata, R., Osawa, S. Phenotypes represented by a mutational change in a 50 S ribosomal protein component, 50–8, in E. coli. Mo. gen. Genet. 114 (1971) 9–13.
Drews, J., Georgopoulos, A., Laber, G., Schütze, G., Unger, J. Antimicrobial activities of 81.723 hfu, a new pleuromutilin derivative. Antimicrob. Ag. Chemother. 7 (1975) 507–516.
Bollen, A., Helser, T., Yamada, T., Davies, J. Altered ribosomes in antibiotic-resistant mutants of E. coli. Cold Spr. Harb. Symp. quant. Biol. 34 (1969) 95–100.
Brockmann, R. W. A mechanism of resistance to 6-mercaptopurine: metabolism of hypoxanthine and 6-mercaptopurine by sensitive and resistant neoplasms. Cancer Res. 20 (1960) 643–653.
Reyes, P., Hall, T. C. Synthesis of 5-fluorouridine 5'phosphate by a pyrimidine phosphoribosyltransferase of mammalian origin. II. Correlation between the tumor levels of the enzyme and the 5-fluorouracil-promoted increase in survival of tumor-bearing mice. Biochem. Pharmacol. 18 (1969) 2587–2590.
Richmond, M. H., Jack, G. W., Sykes, R. B. The β-lactamases of gramnegative bacteria including Pseudomonads. Ann. N. Y. Acad. Sci. 182 (1972) 243–257.
Steuart, C. D., Burke, P. J. Cytidine deaminase and the development of resistance to arabinosyl-cytosine. Nature (New Biol.) 233 (1971) 109–110.
Wolpert, M. K., Ruddon, R. W. A study on the mechanism of resistance to nitrogen mustard (HN2) in Ehrlich ascites tumor cells: comparison of uptake of HN2-14-C into sensitive and resistant cells. Cancer Res. 29 (1969) 873–879.
Hirschberg, E., Kream, J., Gellhorn, A. Enzymatic deamination of 8-azaguanine in normal and neoplastic tissues. Cancer Res. 12 (1952) 524–528.
Smith, J. T.: Personal communication, 1975.
Connamacher, R. H. Inducible bacterial resistance. In: Antibiotics and Chemotherapy (Ed.:Hahn, F. E.) pp. 8–66. Karger, Basel 1976.
Chabbert, Y. A., Baudens, B. G., Gerbaud, G. R. Variations sous l'influence de l'acriflavine et traduction de la resistance à la kanamycine et au chloramphenicol chez des Staphylocoques. Ann. Inst. Pasteur 91 (1959) 225–230.
Dunsmore, C. L., Pim, K. L., Sherris, J. C. Observations on the inactivation of chloramphenicol by chloramphenicol-resistant staphylococci. Antimicrob. Ag. Chemother. 3 (1963) 500–506.
Kono, M., Kasuga, T., Mitsuhashi, J. Drug resistance of staphylococci. IV. Resistance patterns of some macrolide antibiotics in Staph. aureus isolated in the United States. Jap. J. Microbiol. 10 (1966) 109–113.
Inoue, M., Hashimoto, H., Mitsuhashi, S. Mechanisms of tetracycline resistance in Staph. aureus. I. Inducible resistance to tetracycline. J. Antibiotics (Tokyo) 23 (1970) 68–74.
Izaki, K., Kiuchi, K., Arima, K. Specificity and mechanisms of tetracycline resistance in a multiple drug resistant strain of E. coli. J. Bact. 91 (1966) 628–633.
Dean, A. C., Giordan, B. L. The development of resistance of Bact. lactis aerogenes. II. Production of highly resistant strains in nonselective conditions. Proc. roy. Soc. Bact. 153 (1961) 329–338.
Franklin, T. J., Rownd, R. R-factor mediated resistance to tetracycline in Proteus mirabilis. J. Bact. 115 (1973) 235–242.
Barber, J. The incidence of penicillin sensitive variant colonies in penicillinase-producing strains of Staph. pyogenes. J. gen. Microbiol. 3 (1949) 274–281.
Harmon, J. A., Baldwin, J. N. Nature of the determinant controlling penicillinase production in Staphylococcus aureus. J. Bact. 87 (1964) 593–597.
Novick, R. P., Richmond, M. H. Nature and interactions of the genetic elements governing penicillinase synthesis in Staphylococcus aureus. J. Bact. 90 (1965) 467–480.
Sabath, L., Jago, J., Abraham, E. P. Cephalosporinase and penicillinase activities of a β-lactamase from Pseudomonas pyocyanea. Biochem. J. 96 (1965) 739–752.
Jacob, F., Monod, J. On the regulation of gene activity. Cold Spr. Harb. Symp. quant. Biol. 26 (1961) 193–211.
Imsande, J., Zyskind, J. W., Mile, I. Regulation of staphylococcal penicillinase synthesis. J. Bact. 109 (1972) 122–133.
Dunsmore, C. L., Pim, K. L., Sherris, J. C. Observations on the inactivation of chloramphenicol-resistant Staphylococci. Antimicrob. Ag. Chemother. 3 (1963) 500–506.
Mitsuhashi, S. Drug action and drug resistance in bacteria. 2. Aminoglycoside antibiotics. University Park Press, Baltimore 1975.
Doyle, F. P., Nayler, M. P. The biochemistry and function of β-lactamase. Advanc. Enzymol. 28 (1966) 237–321.
Neu, H. C., Winshell, E. B. In vitro studies of cephanone, a 3-heterocyclic thio-methyl cephalosporin derivative. J. Antibiot. (Tokyo) 26 (1973) 153–156.
Neu, H. C. Cefamandole, a cephalosporin antibotic with an unusually wide spectrum of activity. Antimicrob. Ag. Chemother. 6 (1974) 177–182.
Daoust, D. R., Onishi, H. R., Warrick, H., Handlin, D., Stapley, E. O. Chephalomycins a new family of β-lactam antibiotics: antibacterial activity and resistance to β-lactamase degredation. Antimicrob. Ag. Chemother. 3 (1973) 254–261.
Neu, H. C. Cefoxitin, a semisynthetic cephamycin antibiotic: resistance to β-lactamase inactivation. Antimicrob. Ag. Chemother. 6 (1974) 170–176.
Stöffler, G., Tischendorf, G. W. Antibiotic receptor-sites in Escherichia coli ribosomes. In: Topics in infectious diseases. Drug receptor interactions in antimicrobial chemotherapy (Ed.:Drews, J., Hahn, F.), pp. 117–143. Springer, Wien-New York 1975.
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Drews, J. Parameters of acquired resistance and their role in the evaluation of new chemotherapeutic drugs. Infection 4, 61–69 (1976). https://doi.org/10.1007/BF01638718
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DOI: https://doi.org/10.1007/BF01638718