K う〃 and ″ / ・ C わ e な記ル″〃面 0 加可 the 立″ of イな切 fe ル〃 175 dilution as compared with the toxicity of the hydrogen ion. 9. The bases potassium, sodium, lithium, and ammonium hydroxide act in relation tO their degree Of dissocia- tron, SO that the actlon is due to the concentration Of hydroxyl ions in SO- lution. Hydrogen ions are for anthrax spores, and tO a greater degree for S な 2 0 じ 0 じじツ 0 4 ″ , a stronger poison than hydroxyl ions. 10. The disinfecting action of the halogens chlorine, bromine, and i()dine decreases 1 ore rapidly With increasing atomic weight than would be expected from their chemical propertles. 11. The oxidizing agents nitric acid, dichromic acid, chloric acid, persul- furiC acid, and permanganic acid dis— infect in degrees corresponding to their positions in the electro-chemical series. Chlorine does not correspond t0 this relationship but exerclses a strong specific activity. 12. The disinfecting action of vari- ous oxidizing agents is significantly increased by the addition of hydro- acids of halogens (for example, potas- sium permanganate with hydrochloric acid). 13. We have confirmed the obser- vation of Scheurlen that phenol solu- tions disinfect better after the addition of salts. A good explanation of this phenomenon could not be derived from the present experiments. 14. We have confirmed the well known fact that substances dissolved in ethyl 引 coh 司 , methyl 引 coh 司 , and ethyl ether have almost no effect on anthrax spores. 15. The disinfecting action of aque- ous solutions Of silver mtrate and mercuric bichloride is significantly in- creased by the addition of certain amounts of ethyl alcohol, methyl al- C0h01 , and acetone. 16. The disinfecting action of aque- ous solutions of phenol and formalde- hyde decreases upon the addition of h ) , 1 alcohol or methyl alcoh 司 . 17. The disinfecting action of metal salts is in general weaker in broth, gelatin, body fluids, and the like, or in aqueous SOlutions containing these liquids, than it is in pure water. prob- ably this decrease in activity is due to a reduction in the concentratron of the metal ion solution. 18. NO conclusions can be drawn about the growth inhibiting properties of a substance from the knowledge Of its bactericidal activity. 19. lt is probable that the degree Of electrolytic dissociation of the metal salt has a less significant effect on the growth inhibiting properties of the substance than it does on the bacteri- cidal properties. 、 he former more probably a function of the concentra- tion Of the metal in the nutrient solu- t1011. 20. General laws can be derived for the relationship between the concen- tratlOn and the toxicity of mercurrc bichloride solutions. lt is probable that similar relationships will be discovered for the solutions of other substances. We want to express our extreme thanks to Herr Geheimrath P. ZweifeI and Herr Professor Ⅵを Ostwald, in whose laboratories the preceding work was carried out. They showed con- tinual interest ln our experiments and offered many helpful suggestions. CO 〃〃 e 〃 t This paper tackles the problem of dis- bility of bacterial cells and spores, there infection With typical German thorough- was a large amount Of confusion about ness. Although Koch and others had the basic processes involved. This paper studied the actlon 0f chemicals on clarified a number 0f concepts and was
174 pure solutions Of the agent, it IS nec- essary tO add small amounts Of the agent in question tO a nutrrerit liquid of variable composition, which usually contams a large amount Of substances. ln this way, the disinfect- agent undergoes more or less severe changes and assumes quite dif— ferent properties than it possesses ln pure solution. lt is probable that in growth in- hibition, where the time does not enter as a factor, the degree Of dissocia- tion of the compound plays a reduced role, and it is only the concentratlon Of the metal dissolved in the nutrient fluid which is important. Studies on the growth inhibiting properties Of varrous metal salts in nutrient solutions have been reported many times in the literature. Above all may we mention here the work of von Behring. H e te sted the growth inhibiting propertles of mercury salts in blood serum. For 14 different salts, he found an inhibiting concentration varying between one gram-molecular weight in 2200 liters ( Hg = 1 / 1 1 , 00 の and 6400 liters ( Hg 1 / 32 , 00 の . The agent giving the lowest inhibitory activity was a mrx- ture Of mercuric bichloride With 5 n10 に S Of tartaric acid. The most active compound was K2HgCyanide4. Our experiments were performed in nutrient broth and gelatin. AIthough they are not completed, ℃ have con- firmed von Behring's results that K2HgCyanide4 inhibits better than mercuric bichloride. The activity of the former iS one gram-molecule per 30 , 000 liters, while the latter is one ln 20 , 000 liters, in nutrient gelatin. When these results are compared with those of von Behring, they indicate the great dependence on the nature Of the me- dium. [There f0110W detailed data on the action Of a variety Of substances, and CHEMOTHERAPY the results are summarized in the con- clusions. ] CONCLUSIONS We can summarrze the results Of the preceding studies briefly: 1. Comparative studies on the tOXICl Of vanous substances must carrre out With eClUimOIeCUIar con— centratlons. 2. The disinfectant action of solu- uons Of metal salts depends not alone on the concentration Of the dissolved metal but is 引 so dependent on specific properties Of the salt and the SOlvent. 3. Solutions of metal salt in which the metal portion is in a complex ion, and the concentratlon Of the metal ion itself is very small, have very poor disinfecting powers. 4. The actron of a metal salt de- pends not only on the specific action Of the metal ion but also on the anion and the undissociated portion. 5. HaIogen compounds of mer- cury (including thiocyanate and cy- anate) act in proportion tO their degree Of dissocratlon. 6. The disinfecting power of aque- ous solutions Of mercuric bichloride are reduced by the addition of halogen compounds 0f other metals or hydro- chloric acid. 7. The disinfecting power of aque- ous solutions Of nitrate, mer— cur1C sulfate, and mercurrc acetate is significantly increased b the addition Of moderate amounts 0 sodium chlo— ride. 8. Acids disinfect in general in re- lation tO their degree Of dissociation. Therefore, their actron is a function Of the hydrogen ion concentration in solution. Anions Of the acids, and the undissociated molecules of hydroflu- or1C, nitr1C and triChIoracetIC acids exhibit a specific toxicitv. This spe- CifiC effect decreases with increasing
Krönig 4 〃 d Paul ・ C 加な記ル〃〃面 0 可 the 立″可市可〃 0 れ 173 being removed or added to.* ln this way the viability 0f the bacteria will be more or less lnfluenced. 2. The dissolved substance can pen- etrate the membrane and enter intO chemical reactlon with the proto- plasm. ln the latter case, the speed of dis- infection will depend upon the speed at which the dissolved material pene- trates the membrane, and from the reaction Of the agent with the proto- plasm. Since for disinfecting purposes or- dinarily relatively dilute solutions are used, 、 ve must concern ourselves prl— marily with these last tWO factors. Diffusion. The study of diffusion through organized membranes has been made exceedingly diffcult be- cause Of the fact that varlous sub- stances dO not penetrate the membrane in the same manner. For example, SO- dium chloride diffuses unhindered through a fish bladder, while protein materials are withheld. However, by depositing certain precipitates in th1S membrane, 1 [ can be made more or less impenetrable for a large number 0f sal . ln many experiments it has been shown that the living cell has similar semipermeable membranes. ln bacterla we must further dis- tinguish between the membrane Of a vegetative form and that Of a spore. 、、一 e may correctly assume that the latter is more poorly permeable than the former. Above , the large influence the nature of the cell wall has on the ac- tion Of the disinfectant must be con- sidered. 、、一 e can only derive a clear picture Of the actlon Of a solution on a bacterial cell when we know both the rate at which the substance dif- fuses through the cell membrane, and the reactlon rate which the substance 物 [ Osmotic pressure effect. ] undergoes with the cell body, i. e. , the protoplasm. A certmn evaluation Of the action Of different substances on the proto- plasm of the bacterial cell can at the time be obtained, When ℃ compare substances which because Of their similar chemical properties can be ex— pected tO have similar diffusion rates through the membrane. ln this way, the influence Of diffusion can tO 2 certain extent be ignored. Reactions with the protoplasm. AI- though the chemical compositron of protoplasm is at present almost un- known, itS reaction With chemical agents can be assumed tO fOllOW the general laws which govern ordinary chemical reactions. Therefore the re- action rate will be dependent on the time, temperature, concentratron, and the specific properties Of the reacting substances. GROWTH INHIBITION Ⅵ市翫 the preceding has dealt ex- clusively with the 厄 thal action of the varrous substances, we would like tO consider in the following various Ob- servatlons 、 VhiCh have been made on the growth inhibiting properties which metal salts may exhibit when dissolved in nutnent media. The bactericidal action of a solu- tion depends on the concentration Of the active grouping and the time dur- ing which action is allowed. ln considering growth inhibiting properties, the time Of action does not enter intO the considerations, but it IS only the concentration Of the actlve substance which iS determinative. Therefore 、 ve can not use directly data on the bactericidal actlon Of a substance tO dra 、 V direct conclusions on the growth inhibiting properties. Because it iS not POSSible tO determine the growth inhibiting properties in
24 SPONTANEOUS GENERATION AND FERMENTATION CO ″〃 e 〃 t This work was performed independ- ently of Schwann's, and confirms his for the most part. The student should note that the real reason these tWO workers came up With the same observatlons at the same tlme was probably due to the production Of better nucroscopes, as Cagniard-Latour mentions. Since the yeast cell is quite small in comparison tO plant and animal cells, it would take at least 400 magnifications to be able to discern cellular details. lt was this greater magnification which enabled Cagniard- Latour tO differentiate yeast cells from globules of coagulated egg albumin. author's observatrons on some 0f the physiological properties of the yeast are interesting. The yeast cell's ability tO grow anaerobically and to withstand freezrng and desiccation are well con— firmed today. Many other microorgan- lsms, including some pathogenic ones, alSO possess these propertles. This paper and the preceding one by Schwann gave Henle support for h1S early germ theory of disease. See page 76. Concermng the phenomena Of fermentatron, putrefaction, and decay, and their causes ノ 839 ・ / 〃立なん g Liebig, Justis. 1839. Ueber die Erscheinungen der Gährung, Fäulniss und Verwesung, und ihre Ursachen. / れ na 〃 der P わ 4 〃 C 〃 , VoI. 48 , pages 1 ー 150. I WISH NOW TO DRAW THE attention Of natural scientists tO a pre- viously undiscovered cause for the changes and decompositions which in general are known as d どじ 4 ツ , 2 ″な e じ - 0 〃 , fe 〃〃な 0 〃 and Ot 行〃 g. This cause is the ability which a chemical substance possesses, 、 vhen in the process Of decomposition or CO 一 - bination, tO cause or enable another substance which is touching it, tO un- dergo this same change which it itself iS undergoing. The generality 0f this causation can be demonstrated 、 vith countless ex- periences. lt will suffce when I indi- cate only several Of these. PIatinum, for example, does not pos- sess the ability tO decompose in nitric acid and hence tO dissolve in it. Plat- inum alloyed with silver dissolves very easily in nitric acid. The ability which silver possesses IS carried over tO the platinum. [Then follow a num- ber Of Other examples Of the same sort drawn from the chemical literature. ] The indicated examples suffce to prove the exlstence Of this character- iStiC principle. Before I go intO more detailed con-
P な立 e ″・沢 e20 0 れオ C 〃じ 4 じ〃 e 0 27 10 ℃ r order, as a result Of a neutraliza- tion Of the equllibrium in the attrac- t10n Of their elements. The following disturbances will bring about decompositlon: (a) Heat which is in the process of changing ・ (c) The influence of a substance stances (b) Contact with different sub- CO ″れ t I have translated only a small portion of this long, rambling account. lts in- clusion in thiS collection iS only war— ranted because Liebig was 2 powerful figure who was able, by sheer weight of prestige, tO influence 2 number Of lesser scientists. Because Of this the controversy OVer spontaneous generatlon ex— tended for another generation. lt will be noted that there is little experimental work in Liebig's paper. He starts from a position Of pure prgudice, and consequently cannot but conclude as he does. This paper should be 2 contmuous ObJect lesson tO all scientrsts, young and old, that one good experiment is worth one hundred bad theories. This should not be taken to mean that Liebig did not make significant contri- but10ns tO SCience. a great chem— lSt, and S convinced that 2 Ⅱ vital activity could be explained in terms 0f chemistry and physics. Much of the his- tory of biochemistry had its beginmngs in the work of Liebig and his school. lt is unfortunate that he took the view he did on the putrefactive process, srnce this probably dela ed for a number of years the rise 0 microbiology as a scrence. Report on the lactic acid fermentatlon (author's abstract) T ゐ 0 g 切 al F 〃 c t な叩 2 な切 the / 22e れ市も 24g 2 ー 2 石 7. 7 め 7 ・も 0 〃な P の肝 Pasteur, L. Mémoire sur la fermentatlon appelée lactique. (Extrait par l'auteur). Co 2 ゞれ d de I ' / 砌イ e イ〃 0 , Vol. , pages 913- 916 , 1857. MY WORK ON THE PROPERTIES OF THE amyl alcohols and on the very remark- able crystallographic properties of their derivatives has led me tO a study Of the process Of fermentation. Later I will have the honor to present to the Academy observations WhiCh ShOW an unexpected relationship between fermentation and the optically actlve properties 0f organic molecules found ln nature. The necessary materials for the prtaration and production of 1 。 0i0 are ℃Ⅱ known tO chemists. lt iS known that it IS only necessary tO take a solution of sugar and add chalk, which keeps the medium neutral, a mtrogenous material, such as
160 lsolation Of a crystalline protern possessing the properties Of tobacco-mosarc VIrus 1935 ・Ⅳ印売〃 M. & 衂 I VIROLOGY Stanley, 、 V. M. 1935. lsolation of a crystalline protern possesstng the properties 0f tob acco- mosaic V1rus. Sc れ 0 ら VOI. 81 , NO. 21B , pages ょ CRYSTALLINE MATERIAL, WHICH HAS the properties Of tobacco-mosarc has been isolated from the juice 0f Turkish tobacco plants infected with this virus. The crystalline material contains 20 per cent. nitrogen and 1 per cent. ash, and a SOlution containing 1 milligram per cubic centimeter a positive test with Millon'S, xanthoproteic, glyoxylic acid and Folin's tyrosine reagents. The M01isch and Fehlings tests are even with concentrated solutions. 、 he ma- terial is preci itated by 0.4 saturated ammoruum su fate, by saturated mag- nesrum sulfate, or by safraninq ethyl alCOhOl, acetone, trichloracetic tannic acid, phosphotungstic acid and lead acetate. The c stalline protein iS practically insolub e in water and is soluble in dilute acid, alkali or salt solutions. solutions containing from 0.1 per cent. t0 2 per cent. Of the pro- tein are opalescent. They 2 代 fairly clear between pH 6 and 1 1 and be- tween pH 1 and 4 , and take on a dense whitish appearance between PH 4 and 6. The infectivity, chemical composi- tlOn and optical rotation Of the cr s- talline protein were unchanged a ter 10 successrve crystallizations. ln a fractional crystallization experiment the act1Vity 0f the first small po 山 on Of crystals tO come out Of solution was the same as the activity Of the mother liquor. When SOlutions are made more alkaline than about pH 11.8 the opal- 000 。 00 d P 「 000 and 市 ey b00 。 00 C 厄 ar. such SO utl()ns are devoid Of ac- tivity and it was shown by solubility tests that the protein had been dena- tured. The material is also denatured and itS acuvity lOSt when solutions are made more acid than about pH 1. lt is com letely coagulated and the ac- tl ⅵ ost on heating t0 94 。 C. Pre- liminary experiments, in which the amorphous form Of the protein was partially digested with pepsin, or par- tially coagulated by heat, indicate that the IOSS in activit iS about propor- tional tO the IOSS O native protein. The molecular weight Of the protein, as determined by two preliminary ex- perrments on osmotic pressure and diffusion, is of the order of a few millions. That the molecule is quite large is also indicated by the fact that the protein is held back by collodion filters through which proteins such as egg albumin readily pass. C0110dion
164 area Of inorganic and orgamc chem- istry a series Of general la , S. Since the physiological activity of sub- stances iS in general dependent upon chemical properties, one can expect that the study of disinfection will also find new vrewpoints through these new chemical theories. We have set for ourselves the task of studying the behavior of bacteria with chemical agents from the basis Of these vrewpoints, in order, per- haps, to be able t0 use the results obtained for the development of prac- tical disinfectlon procedures. Although there is in the literature a large number Of observations on the actIOn Of different disinfectants on bacteria in pure solutlons, we have carried out anew 2 large senes Of ex- periments, since the previous results have partly disagreed with each other and are Often not directly comparable, Slnce the ex enments had been run under a ' 1 e variety Of conditions, SO that the temperatures were not the same, and the test organisms differed, and SO on. Before we proceed tO our ments, we must examine briefly hOW one can determine the disinfecting properties Of 2 solution and What con— ditions must be kept constant, in order tO be able tO compare the disinfectant properties Of different solutions. 1. First, equimolar amounts of the varl()us substances must be used in the comparatlve expenments. 2. The bacteria to be used as test organisms must all have the same re- SlStance. 3. The number of bacteria used in each experiment must be the same. 4. The bacteria must be placed in the disinfecting solutions ln such a way that none Of the nutrient ma- terlals on which they were cultured are carried over With them. 5. The disinfecting solutions must always have the same temperature. CHEMOTHERAPY 6. After the action of the disinfect- lng agent, the bacterra must be again completely freed from this agent. 7. After the bacteria have been re- moved from the disinfecting solution, they must be placed on equal amounts Of the same suitable medium at the same temperature, which if possible should be the optimum for their growth. 8. The number of remaining bac- teria capable Of reproducing intO C01- omes on SOlid medium must be counted after the same length Of in- cubation time. We have attempted to follow these rules in the performance Of our ex- periments, SO far as POSSible. 7. CO 2 な 0 れ of 9 0 c ln the literature, the experiments on disinfection almost always report the concentration Of the solutions in per cent b weight. AS ong as 耽 IS not necessary tO compare the activity Of tWO agents, the expresslon Of concentration in per cent is not only the easiest, but for practical use it IS the most suitable. A simple consideration will ShOW, hOW- ever, that for comparative studies only equimolecular amounts Of the sub- stances may be used. From the theory Of van 't を IO 窟 , a substance in SOlu- t10n iS lll a comparable condition tO a gas; in relation tO temperature, pres- sure, and volume both types show a perfectly analogous behavior, so that we can apply the gas laws directly tO solutions. A gram-molecular weight 0f every gas at the same temperature and pres- sure assumes the same volume. Fur- ther, from Avogadro's 12W , all gases at the same volume and at the same temperature and pressure contain the same number Of molecules. AISO, SOlu- tions Of the same VOlume contaimng
D ' 〃 e 〃ビ・ / 〃切みなみ e 4 な go が立な地厩 e リみ 4 〃 159 Shiga bacillus. These latter properties ℃ re attenuated in succeeding cul- tures. ln summary, in certain convalescents from dysentery I have shown that the disappearance 0f the dysentery bacilli IS coincident with the appearance Of an invisible microbe endowed With antagonistic properties against the pathogen. This microbe, really a ml- crobe Of immunity, iS an obligate bac- teriophage. lts parasitism iS strictly specific, but if it iS restricted tO a cer- tain species, it is gradually able t0 acqurre actlV1ty agamst various gerrns. lt seems therefore that in the dysen- tery bacillus, as well as a homologous immunlty coming directly from the person infected, there eXlStS a hetero- logous immunity coming from an an- tagomstic microbe. lt is probable that thiS phenomenon IS not restricted tO dysentery, but that it is of general significance, because I have been able tO observe a similar S1tuat10n, even though weaker, in t ℃ cases Of para- typhoid fever. CO ″″〃 e 〃 t This discovery of bacteriophages, or bacterial viruses, was actually first made by Twort in 1905. But his work is not t00 clear and was not followed up, SO that I have included here the paper by d'Herelle, which was really responsible for the beginning Of extensive scientific work on these lnteresung organrsms. MOSt species Of bacteria that have been studied have been shown tO be hosts for bacterial viruses. AS d'Herelle sus- pected, the phenomenon widespread. But his early hopes that bacterial viruses would be useful in treating bacterial in- fections or ln conferring immunity have not been fulfilled. d'HereIIe had little understanding Of the word 'fimmunity as we use 1 [ , since the Of a bac— terial virus could not be expected to in- duce antibody formation against a bac- terrum. The bacterial Viruses have remained essentially laboratory ties. They have been used as model sys- tems for the study of viral reproduction and have made great impact on molecular genetics. They have also been used in diagnostic laboratories in the typing of certain widely occurring pathogens, such as & / 0 〃 el な p わ 0 and & 4 々たあ co ← C ″ゞ 4 ″ re ″ゞ . But all trials of their use as therapeutants have been unsuccessful.
230 GENERAL MICROBIOLOGY tained the largest amounts Of sulfur mng, while in the control the amount granules. lt was possible tO Obtain an was just at the limit Of sensitivity of approximate idea 0f the rapidity of the mlcrochemical reaction. The the oxidation phenomenon in the liv- amount Of acid formed in the controls, ing cells by comparing under the mi- due tO a pure chemical oxidation of crosco e the quantlty Of crystals the sulfur of their cells, had a maxi- forme with those formed by known mum 0f 0.0014 to 0.004 per cent, or solutions Of sulfate. about three tlmes the origrnal value. I have found in such an experrment Therefore the physiological role of the following figures. These figures the sulfur bacteria is a purely oxidative were derived from a drop which con- one. Hydrogen sulfide of the medium tained 0.2 ー 0.3 cc. of a liquid contain- IS oxldized in their protoplasm and ing O. OO 14 % sulfuric acid and con- de OSited as sulfur granules in their taining a small floccule 0f B gg 地 4. ce ls. These sulfur granules are trans- formed intO sulfuric acid and ex- After 24 hours 0.00 グ creted. The protoplasm of the living After 48 hours 0.0093 7 orgamsm enters actively intO thiS proc- After 5 days 0.0443 7 ess Of combustion and makes it par- After 8 days 0. 867 ticularly intense. ・ rhe energy that be- The amount of sulfuric acid which comes available in thiS oxidation iS is formed in the liquid surrounding their principle source Of energy, as I the living filaments more than 弭 have shown in special expenments, tlmes what it had been at the begin- making them umque beings ・ CO 冖 e ま This paper is one of the early works propertles lll mcroscopic culture. Be— of Winogradsky on the properties of the cause the sulfur granules SO easy chemosynthetic bacteria. He had pre- tO see, it was quite simple tO shOW that viously worked on the iron bacteria, and these were only formed when hydrogen now his work on the sulfur bacteria ex- sulfide was present under aerobic condi- tended further 2 whole new field of t1011S. Under anaerobic conditions he microbiology, concerning orgamsms showed that the reduction Of sulfur com- that could derive their energy from the pounds to hydrogen sulfide took place oxidation Of inorganrc compounds. At rnstead. He inferred without proving it the time of the present work he had not that this reduction process was due to yet formulated completely the idea that Other orgamsms, WhiCh ℃ these organisms used the energy from to be those of the genus D の fo ⅵ房 . lnorganrc oxidatlons tO fiX carbon diOX- After showing the initial oxidation to ide intO organic compounds Of their pro- sulfur granules, he proceeded to demon- toplasm. But he showed quite clearly strate that these granules could then be that the sulfur bacteria could convert, oxidized further to sulfuric acid, and under aerobic conditions, hydrogen sul- that this process only occurred when the fide into free sulfur, and this into sul- organism , as alive. HiS clever technique furiC acid. for demonstrating the production of sul- He was working with an organism that furiC acid in mcrocultures iS quite nota— IS quite large and easy tO see under the ble. The crystals of barium sulfate are mrcroscope. ItS presence sulfur waters distinctive enough to be readily iden- was ℃Ⅱ known, and because it occurred tified, and he was also able to perform in clumps it was easily available for crude quantitative experiments on the study. Without the pure culture meth- amount Of acid formed. ods which he later worked out, he found There were many things left to be diffcult to study this organism ln mass done with the sulfur bacteria after these culture but succeeded in working out lts experiments, and it was 2 long time be-
CHEMOTHERAPY 204 T VII ela 0 み ue 印 CO 加 e れ〃可ゆわ 4 腕 e 4 れイ CO れ c な 0 れ of Factor Re 4 耘 e イ地 Rev the 0 ル Quantities of Extracts A and B are expressed as ml. "standard 代 n 部 h Streptococcus Ba . CO 〃・ Streptococcus 0 ′ g な川 p-aminobenzorc acid Extract A Fac ー 0 イ : Conc. required ml. required ml. required Conc. sulphan. (M X 10 ー 7 ) Ratio: (X 10 ー 1 ) Ratio: t (X 10 ー 1 ) Ratio: t (M x 10 ー 3 ) (d) (c) (b) (a) 058 0.08 0.016 0303 2.91 0.4 1.515 0.08 14.54 2.0 04 7.575 ・ The of Ba け . co 〃 and the medium em 可 oy 記 (lactate 十 inorganic salts) were those used by Fildes ( 19 ). ・ rhese arbitrary ratlOS are an expression Of the 靆ロ 0 : conc. factor required/conc. sul- phanilamide Ⅱ s 記 . boxylic the first substance tested was the chemical properties 0f the factor p-aminobenzorc acid. ln this acid the 引 so indicated the possibility that the p-NH2 of sulphanilamide is unchanged factor might be chemically related t0 but —S02NH2 is replaced by ー COOH. sulphanilamide. Examples 0f known p-amnobenzorc acid proved tO have cases Of competltive inhibition Of en- very high activity, and a 五 nal con- zyme reactrons by substances related centration 0f 1.2 ー 5.8 X 10 ー 8 M was tO the substrate or products are: (a) suffcient tO reverse the inhibition succinic dehydrogenase by malonic caused by 3.03 X 10 ー 4 M sulphanila- acid, (b) lipase (hydrolysls 0f ethyl mide (). e. , 0.02 .1 g. in 1 1 ml. me- butyrate) by acetophenone and other dium compared with 570 g. sulphanil- non-polar compounds containing a car- amide). The results 0f a number 0f bonyl group, and (c) invertase by quantltative determrnatlons are given and ß-galactose and ß-l-arabinose. in Table VIII. The agreement between As it was possible tO interpret these separate determrnations tWO distinct lines Of evidence (chemi- variation by a factor Of 5 ) is satis- C21 properties and behaviour in growth factory in view 0f the high dilutions tests) in the same ' ay , it seemed used and possible differences in the worth while at this stage tO test for state Of the inoculum. Duplicates in anti-sulphanilamide activity S01 e the same determination did not show pounds which are structurally related this varntion. t0 sulphanilamide, and whose proper- ties are reasonabl in accord with pu Of 2- m ア 0 み e 0 な 4 房イ . those Of the yeast actor. Table VIII also shows that the ac- ANTI-SULPHANILAMIDE ACTIVITY OF t1Vity Of p-aminobenzoic acid is un- P-AMINOBENZOIC ACID affected by recrystallizin five times. . From the methOd O preparation ln view 0f the probability that the the most likely impurities are the 0- acid group Of the factor was car- Extract B 1.92 1.92 1.92 265 265 265