soil samples-help which consisted mostly of bottle-washing and making dilutions-Paige learned the reasoning well enough to put forward a version of it himself. He practiced it on Anne over dinner.
"It all rests on our way of thinking about why antibiotics work," he said, while the girl listened with an attentiveness just this side of mockery. "What good are they to the organisms that produce them? We assumed that the organism secretes the antibiotic to kill or inhibit competing organisms, even though we were never able to show, that enough antibiotic for the purpose is actually produced in the organism's natural medium, that is, the soil. In other words, we figured, the wider the range of the antibiotic, the less competition the producer had."
"Watch out for teleology," Anne warned. "That's not why the organism secretes it. It's just the result. Function, not purpose."
"Fair enough. But right there is the borderline in our thinking about antibiosis. What is an antibiotic to the organism it kills? Obviously, it's poison, a toxin. But some bacteria always are naturally resistant to a given antibiotic, and through-what did your father call it?-through clone-variation and selection, the resistant cells may take over a whole colony. Equally obviously, those resistant cells would seem to produce an antitoxin. An example would be the bacteria that secrete penicillinase, which is an enzyme that destroys penicillin. To those bacteria, penicillin is a toxin, and penicillinase is an antitoxin-isn't that right?"
"Right as rain. Go on, Paige."
"So now we 'add to that still another fact: that both penicillin and tetracycline are not only antibiotics-which makes them toxic to many bacteria-but antitoxins as well. Both of them neutralize the placental toxin that causes the eclampsia of pregnancy. Now, tetracycline is a broad-range antibiotic; is there such a thing as a broad-range antitoxin, too? Is the resistance to tetracycline that many different kinds of bacteria can develop all derived from a single counteracting substance? The answer, we know now, is Yes. We've also found another kind of broad-range antitoxin-one which protects the organism against many different kinds of antibiotics. I'm told that it's a whole new field of research and that we've just begun to scratch the surface.
"Ergo: Find the broad-range antitoxin that acts against the toxins of the human body which accumulate after growth stops-as penicillin and tetracycline act against the pregnancy toxin-and you've got your magic machine-gun against degenerative disease. Pfitzner already has found that antitoxin: its name is ascomycin. . . . How'd I do?" be added anxiously, getting his breath back.
"Beautifully. It's perhaps a little too condensed for MacHinery to follow, but maybe that's all to the good-it wouldn't sound authoritative to him if he could understand it all the way through. Still it might pay to be just a little more roundabout when you talk to him." The girl had the compact out again and was peering into it intently. "But you covered only the degenerative diseases, and that's just background material. Now tell me about the direct attack on death."
Paige looked at the compact and then at the girl, but her expression was too studied to convey much He said slowly: "I'll go into that if you like. But your father told me that the element of the work was secret even from the government. Should I discuss it in a restaurant?"
Anne turned the small, compact-like object around, so that he could see that it was in fact a meter of some sort. Its needle was in uncertain motion, but near the zero-point. "There's no mike chose enough to pick you up," Anne said, snapping the device shut and restoring it to her purse. "Go ahead."
"All right. Some day you're going to have to explain to rue why you allowed yourself to get into that first fight with me here, when you had that Eavesdropper with you all the time. Right at the moment I'm too busy being a phony
"It all rests on our way of thinking about why antibiotics work," he said, while the girl listened with an attentiveness just this side of mockery. "What good are they to the organisms that produce them? We assumed that the organism secretes the antibiotic to kill or inhibit competing organisms, even though we were never able to show, that enough antibiotic for the purpose is actually produced in the organism's natural medium, that is, the soil. In other words, we figured, the wider the range of the antibiotic, the less competition the producer had."
"Watch out for teleology," Anne warned. "That's not why the organism secretes it. It's just the result. Function, not purpose."
"Fair enough. But right there is the borderline in our thinking about antibiosis. What is an antibiotic to the organism it kills? Obviously, it's poison, a toxin. But some bacteria always are naturally resistant to a given antibiotic, and through-what did your father call it?-through clone-variation and selection, the resistant cells may take over a whole colony. Equally obviously, those resistant cells would seem to produce an antitoxin. An example would be the bacteria that secrete penicillinase, which is an enzyme that destroys penicillin. To those bacteria, penicillin is a toxin, and penicillinase is an antitoxin-isn't that right?"
"Right as rain. Go on, Paige."
"So now we 'add to that still another fact: that both penicillin and tetracycline are not only antibiotics-which makes them toxic to many bacteria-but antitoxins as well. Both of them neutralize the placental toxin that causes the eclampsia of pregnancy. Now, tetracycline is a broad-range antibiotic; is there such a thing as a broad-range antitoxin, too? Is the resistance to tetracycline that many different kinds of bacteria can develop all derived from a single counteracting substance? The answer, we know now, is Yes. We've also found another kind of broad-range antitoxin-one which protects the organism against many different kinds of antibiotics. I'm told that it's a whole new field of research and that we've just begun to scratch the surface.
"Ergo: Find the broad-range antitoxin that acts against the toxins of the human body which accumulate after growth stops-as penicillin and tetracycline act against the pregnancy toxin-and you've got your magic machine-gun against degenerative disease. Pfitzner already has found that antitoxin: its name is ascomycin. . . . How'd I do?" be added anxiously, getting his breath back.
"Beautifully. It's perhaps a little too condensed for MacHinery to follow, but maybe that's all to the good-it wouldn't sound authoritative to him if he could understand it all the way through. Still it might pay to be just a little more roundabout when you talk to him." The girl had the compact out again and was peering into it intently. "But you covered only the degenerative diseases, and that's just background material. Now tell me about the direct attack on death."
Paige looked at the compact and then at the girl, but her expression was too studied to convey much He said slowly: "I'll go into that if you like. But your father told me that the element of the work was secret even from the government. Should I discuss it in a restaurant?"
Anne turned the small, compact-like object around, so that he could see that it was in fact a meter of some sort. Its needle was in uncertain motion, but near the zero-point. "There's no mike chose enough to pick you up," Anne said, snapping the device shut and restoring it to her purse. "Go ahead."
"All right. Some day you're going to have to explain to rue why you allowed yourself to get into that first fight with me here, when you had that Eavesdropper with you all the time. Right at the moment I'm too busy being a phony
Similar Books
