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//-->History of ScienceSouth African Journal of Science103,September/October 2007377Louis Pasteur, fermentation,and a rivalK.L. Manchester*Accusations of plagiarism, probably unjustified, concerning twoeminent scientists over the first demonstration of fermentation byliving organisms, still persist after a century and a halfONE HUNDRED AND FIFTY YEARS AGO, INAugust 1857, Louis Pasteur gave a lectureto the Société des Sciences de Lille entitled‘Lactate fermentation’, published soonafter as aMémoire.1The title may soundunexciting, but this historic paper markedPasteur ’s first statement of a germ theoryand a specific role for microorganisms inmetabolic processes. Pasteur was then34 and professor of chemistry and deanof the new Faculté des Sciences in Lille(Fig. 1), in the heart of the sugar beetgrowing region of northern France.Pasteur ’s appointment was in part in-tended to give help to industrialists inLille, but the opening sentence of hispaper makes clear that he was led toconsider fermentations following his re-searches on the amyl alcohols and theirremarkable crystallographic properties.2His studies on fermentations led to a pro-tracted dispute with a contemporary,Antoine Béchamp, over the priority of hisfindings which, remarkably, is main-tained to this day and with which thelatter part of this article deals.Pasteur’s work on fermentationIt will be recalled that, in 1846, as astudent at the École Normale Supérieurein Paris, Pasteur had had the remarkableperspicacity and good fortune to noticethat the sodium ammonium salt ofparatartaricacid, a form of tartaric acidthat was indistinguishable chemicallyfrom the commonly occurring tartaricacid except that solutions were not opticallyactive, crystallized to give mixtures of twomirror image enantiomorphic forms(Fig. 2). These crystal forms, if carefullyseparated by hand and then dissolved inwater, gave optically active solutions ofopposite rotations.3Given the opticalactivity of many organic compounds ofnatural origin, Pasteur had deducedthat asymmetry (Pasteur used the term‘dissymmetry’) was a feature of the chem-istry of life and that this would correlatewith hemihedral crystals. Optically activeamyl alcohol recovered in distillates fromalcoholic fermentations, particularly of*School of Molecular and Cell Biology, University of theWitwatersrand, Private Bag 3, WITS 2050, South Africa.E-mail: keith.manchester@wits.ac.zagrains, did not fit with this rule, and thisdiscovery had led him to a special interestin the amyl alcohols. Nevertheless, and alittle confusingly, the paper presented inLille dealt instead with lactic fermenta-tion,1Pasteur declaring that: ‘I intend toestablish that, just as there is an alcoholicferment, the yeast of beer, which is foundeverywhere that sugar is decomposedinto alcohol and carbonic acid, so alsothere is a particular ferment, a lactic yeast,always present when sugar becomes lacticacid.’ And this is precisely what he found.Critics have pondered over the yearswhether Pasteur formed his views on thebasis of the evidence or decided what theresult must be and proceeded to prove it!A prevailing view promoted by Justusvon Liebig, up to this time, was that fer-mentation represented a form of decom-position, perhaps initiated by yeastsbut proceeding essentially as a result ofinstabilities arising in molecules in fermen-tation liquors. On this view, amyl alcoholpossessed optical activity because it re-tained some of the properties of thefermenting sugars. Pasteur consideredthat amyl alcohol was too dissimilar tosugars for this to be so (in which he wascorrect), and that its optical activity derivedfrom the living organism producing it (inwhich he was wrong). Subsequent workshowed that the two amyl alcohols offermentation constitute breakdown prod-ucts of the amino acids leucine and iso-leucine, present in nitrogenous materialsin the fermentation media. AlthoughFig. 1.Pasteur in 1857 when dean of the Faculty ofSciences in Lille. [Musée Pasteur, Paris]both leucine and isoleucine exist in dextro(+) and laevo (–) rotatory forms, theirequivalent degradation to optically inac-tive isoamyl acohol and (optically) activeamyl alcohol results in loss of the asym-metry of a carbon atom in isoamyl alcohol,which is retained in active amyl alcohol(Fig. 3). To Pasteur’s considerable distress,the two alcohols, as their bariumsulphamylates, had exactly the same crys-tal form.2Fermentation correlative with lifeYeast, when incubated with sugaralone, gradually disintegrates. Pasteurrecognized this event as one of the mostimportant points in Liebig’s theory offermentation.4If fermentation, Liebigargued, is a consequence of the develop-ment and multiplication of cells, as othersclaimed, incubations containing sugaralone should not produce alcohol, sincesuch a medium lacks the other essentialconditions for cell growth and division.Nevertheless, alcohol is produced underthese conditions.Pasteur showed that it was as a result ofthe growth of yeast cells, which can feedoff the remnants of dead cells, that fermen-tation occurs.4Thus, he reached the cele-brated conclusion that ‘the breakdown ofsugar into alcohol and carbonic acid is anaction correlating with a vital phenome-non’, that is, fermentation is a property ofliving cells. Pasteur was also able to refuteLiebig’s claim by showing that yeastgrows and ferments sugar in mediumdevoid of albuminoid (proteinaceous)material, although containing ammoniaand salts.5But having made one clear and impor-tant advance, Pasteur now risked pushingFig. 2.Hemihedral crystals of (+)– and (–)-sodiumammonium tartrate. Adapted from ref. 22.378South African Journal of Science103,September/October 2007History of ScienceFig. 3.Structures of leucine and isoleucine, and the related amyl alcohols derived from them duringfermentations. Another name for the amyl alcohols is fusel oil, an acrid, oily liquid occurring in insufficientlydistilled alcoholic liquors.himself into a potentially dubious position,this time in relation to vitalism, that isthat certain metabolic properties of livingmatter cannot be observed outside the celland that only those fermentations carriedout by cells were to be regarded as‘proper’ fermentations. There was clearevidence of soluble ferments (that is,enzymes) that operated outside cells, twoof the best-known examples being theactions of diastase on starch and invertaseon sucrose. Thus it was not the fermentthat was living, but the cells that producedit, a point established unequivocally onlywith Buchner’s production, 40 years laterin 1897, two years after Pasteur’s death, ofa juice from yeast capable of ethanolicfermentation.6Pasteur was aware of sucha possibility but was never able experi-mentally to show it, and we know that inBuchner’s case the discovery was largelya matter of luck.Antoine BéchampWhile Pasteur was busy with his fermen-tations, another chemist was also activelystudying the possible influence of livingorganisms to bring about fermentation.Pierre Jacques Antoine Béchamp wasborn the son of a miller in 1816 (Pasteur,the son of a tanner, in 1822). Initiallystudying pharmacy in Strasbourg andteaching in various of the faculties in theuniversity, in 1854 he succeeded Pasteur(who had moved to Lille) as professor ofchemistry. In 1856 he was appointedprofessor of medical chemistry and phar-macy in the faculty of medicine of theUniversity of Montpellier (Fig. 4), wherehe worked for 20 years. Béchamp believedthat a question of pure chemistry oftenAll naturally occurring sugars rotate the plane of polarizedlight to the right [dextrorotatory; a plus (+) rotation] or to theleft [laevorotatory; a minus (–) rotation]. Polarimetry, a pro-cedure dating from the early years of the 19th century, wasonce one of the easiest ways of following a reaction such asthe hydrolysis of sucrose. Sucrose has a specific rotation of+67°, glucose of +53° and fructose –92°. An equimolarmixture of glucose and fructose is therefore laevorotatory,whereas that of sucrose is dextrorotatory. Invertase thuscatalyses a reaction that results in the inversion of the planeof polarization from being to the right to being to the left. Anold name for fructose is invert sugar or laevulose, and forglucose, dextrose (or grape sugar), as opposed to canesugar for sucrose.aturns into one of ‘subtle physiology’.(Presumably the same could be said ofPasteur, where his academic study ofstereoisomerism led to fermentation.)Béchamp was anxious to establish whetherthe partial inversiona(hydrolysis) to glu-cose and fructose of cane sugar, dissolvedin water and left to stand in stopperedbottles at room temperature for up to ninemonths, was the result of an action ofwater alone or had some other cause.His first published work on this topic,7in 1855, was to show that, if to the sucrosesolution he added 25% calcium or zincchloride, no inversion was observed. Inthe solution without salts some mouldappeared within a month, but in subse-quent months it did not increase in extent,though inversion was then taking place.At this date it was known that acids couldbring about inversion of sucrose. Béchampconcluded from this experiment that theacidity of salts was not comparable to theacidity of an acid, yet water acted onthe sucrose by virtue of its acid nature,although not showing an acid reactionwith coloured indicators. He was surprisedto see no effect of zinc chloride, since itshowed an acid reaction. In this paper,Béchamp makes no suggestion that theappearance of the mould was a significantfactor in the occurrence of inversion.Whether the thought had passed throughhis mind we do not know, which is unfor-tunate because it is this uncertainty whichconstitutes the basis of the controversy,which began to erupt around this time,over priority between Béchamp andPasteur as to who first showed the pro-duction of ferments by living organisms.In a subsequent paper,8however, pub-lished at the beginning of 1858, Béchamppointed out that experiments he had con-ducted since 1855 forced him to modifyhis earlier conclusions. He now believedthat cold water alone does not invertsucrose, but that the reaction, when itoccurs, is the result of a ‘true fermenta-tion’. He concluded that moulds do notdevelop in the absence of air and, in theirabsence, inversion does not occur; but ifsimple solutions of sucrose are in contactwith air, then moulds develop and inver-sion occurs in proportion to the develop-ment of the mould. With these findings,Béchamp also regarded himself as thefirst to show the action of ferments insugar solutions in the absence of proteina-ceous material, that is, the ferment had toarise within the living cell.Controversy between Béchamp andPasteur in the academiesThings began quietly. At a meeting ofthe Sociétés des Savantes in 1862, Pasteur,in the presence of Béchamp, claimedprecedence for showing the appearanceof living organisms in a medium devoid ofalbuminoid matter. The meeting report9reads:M. Béchamp quoted some experiments, inwhich the transformation of cane sugarinto grape sugar, brought about under theinfluence of air, is always accompanied bymoulds. These experiments agree with theresults obtained by M. Pasteur, who has-tened to acknowledge that the fact putforward by M. Béchamp is one of the mostrigid exactness.Fig. 4.Béchamp when professor of medical chemistryand pharmacy at the University of Montpellier1857–1875. From ref. 16.The Académie des Sciences was animportant venue for airing and develop-ing views and a place to put forwardnovel ideas. In 1864, Béchamp felt movedto present aMémoire1 0in which hesuggested that only soluble ferments (likeinvertase, to which he gave the namezymase)were constant in their actions.The organized ferments (Pasteur ’s ‘prop-erly called’ fermentations) generatedvariable amounts of products, accordingto circumstances, because they reflectedthe nutritional activities of cells whichHistory of ScienceSouth African Journal of Science103,September/October 2007379consume organic materials, breakingthem down and converting them intosimpler forms. It often requires severalsuccessive fermentations (in modernterms, several enzymes) to produce thetotal effect. For Béchamp, alcoholic fermen-tation and the fermentations by organizedferments are not ‘properly called’ fermen-tations—they are simply manifestationsof nutrition, a remarkably prescient idea.In 1872 we again find Béchamp telling theAcademy11that he believedhewas thefirst to point out that organized fermentscan develop in media in the absence ofproteinaceous material and that fermen-tation is essentially an act of nutritionwhich includes excretion.Conflict erupted yet again at the inter-national medical congress held in Londonin 1881. Describing a session concerningthe role of bacteria in disease,12Béchamp,now from Lille, wrote:M. Pasteur began to lecture and sud-denly, in my presence, before I had said aword, he condemned me in a generalanathema towards all aspects of hetero-genesis.bI was waiting to speak, because Iwas due to lecture after him. But soon Iwas obliged to go down from my place tothe front to sit opposite M. Pasteurbecause he had dared to say “that even ifthere were any points in my results, I hadonly incorporated his ideas and madethem mine”. In short M. Pasteur had justclaimed a priority of views and made anaccusation of unprecedented plagiarism.In an indignant voice I demanded ofM. Pasteur to prove his assertion, since Iwould myself show him that the contrarywas true. M. Pasteur, refusing a publicdiscussion, left the session.accuracy of his experimental methodsfrom the aspersions cast upon them byPasteur.’Études sur la BièreversusLesMicrozymas13In his bookLes Microzymas,published in1883, Béchamp describes how Pasteur, in1876 in hisÉtudes sur la Bière,15‘in coldblood’ tried to demolish him once and forall. Pasteur wrote:The first note of Béchamp on the inver-sion of sucrose is in 1855.7There is nomention there of the influence of moulds,the second where he states this influenceis of 4 January 1858,8after my work onlactic fermentation, published 30 No-vember 18571where I establish for thefirst time that the lactic ferment is an or-ganized living being, that albuminoidmaterials do nothing in the cause of fer-mentation, after also my first work on al-coholic fermentation published on 21December 1857.4What is certain, one is atpains to point out, is that Béchamp, whosince 1855 has not suggested the action ofmoulds on sugar, although he had notedtheir presence, has now modified hisformer conclusions.what he considered the impropriety ofPasteur’s behaviour and the error of hisviews of disease, which he described as‘the greatest scientific silliness of the age’,consumed him for the rest of his longlife.19The microzymesThe microzymes are a form of life thatBéchamp, over a period of 30 years, be-lieved that he had discovered, beginning,as he points out in his book of this name,12with his experiments carried out in the1850s on the influence on moulds on thehydrolysis of sucrose. In the book he triesto bring together all the relevant data thatbrought him to the belief that the micro-zymes are at the basis of all life and death.When examining solutions in which thehydrolysis of sucrose was taking place,Béchamp observed extremely small micro-scopic forms, similar to those seen in fer-mentations. In his paper of 1857 [1858],17he designates them aslittle bodiesand thushe came to regard the molecular granula-tions of the histologists as being organizedand living ferments.Béchamp came up with a startling find-ing in 1866.20It was a well-establishedprocedure to add chalk, mainly powderedlimestone, to lactic and other acid fermen-tations to maintain neutrality. But Béchampasks whether this is the only role of thechalk, which, as well as consisting of thefossil remains of crustaceans, he finds stillcontains a whole generation of extremelysmall organisms, smaller than the yeasts.Not only do they exist, but they are alive,despite their extreme geological age. Theygrow with a rare energy like ferments[yeasts]. They are the most active fermentsBéchamp has encountered and theynourish themselves on very diverse organicsubstances.To the organisms from lime (killedwhen heated to 300°C) Béchamp gives thenameMicrozyma cretae,but microzymes(meaning ‘minute ferments’) are foundeverywhere, including in soil. Béchamp’spaper20is logically presented, with se-quential arguments, and the remarkablenature of his results is clear to him. Couldit be that Béchamp was genuinely observ-ing specific bacteria? Or was it a case ofartefacts in the microscopes of the time?Promotion of Béchamp againstPasteurBéchamp’s views would by now havebeen long since forgotten had they notbeen espoused by anti-vivisectionists andprotagonists of alternative medicine.Pasteur ’s use of experimental animalsaroused the wrath of the former, and thedesire of the latter to believe that diseaseoriginating from microorganisms is aBéchamp goes on to say thatThe Timesnewspaper carried full details of the inci-dent. Actually,The Timesreport of 8August13was more restrained and thesummary of Pasteur’s lecture (deliveredin French, as was Béchamp’s) was directedtowards criticism of the work of CharltonBastian over spontaneous generation.However, Béchamp is reported to have‘affirmed that the microzymas in chalk[see below] did exist and that if Pasteurhas not obtained such results it wasbecause his experiments were badlyconducted. Béchamp held that the causeof disease and death lay in the animalitself.’ The report of the same session intheBritish Medical Journal14describesBéchamp as ‘vindicating his claim topriority in the discovery of the organisms[microzymes] which caused the fermen-tation of milk. He also defended theHeterogenesis could mean either the birth or organizationof a living being otherwise than from a parent of the samekind—a process called by Charlton Bastian arche-biosis—or the generation of animal or vegetable life of loworganization from inorganic (i.e. non-living) matter—calledby Thomas Huxley abiogenesis.bThe implications of this is that the changeof Béchamp’s ideas, which took placebetween his first paper in 18557and thenote which appeared in January 1858,8occurred after he had heard of Pasteur ’swork as presented to the Academy inNovember1and December41857. To us,familiar with long intervals betweensubmission of a manuscript and its even-tual publication, this charge would seemimprobable, but on occasion publicationcould be very rapid.Béchamp’s answers inLes Microzymas12to Pasteur ’s accusations are, first, outragethat Pasteur could make such suggestions,and secondly that all his (Béchamp’s) newideas were contained in his memoir of1857. Unfortunately, the latter does notexist, but an apologist16describes how thismemoir is his paper inAnnales de Chimie,17which for unknown reasons appearedonly in September 1858. Dates of submis-sion of manuscripts are not indicated inthe final publication.It is interesting to note, in parenthesis,how both Béchamp and Pasteur startedtheir careers more as physical scientiststhan biologists, but were gradually ledinto biology through the study of aspectsof fermentation, then turned their atten-tion to the diseases of man and of higheranimals. Béchamp, like Pasteur, alsoworked on the diseases of wine and ofsilkworms, making significant findingswhich did not attract the publicity ofPasteur’s studies, and again Béchamp felthe had reason to accuse Pasteur of plagia-rizing his work.18Béchamp’s anger at380South African Journal of Science103,September/October 2007History of Sciencefiction, set them firmly against Pasteur infavour of Béchamp’s ideas.Following the death of Béchamp in1908, an event ignored in France, a DrMontague Leverson from Baltimorepersuaded a writer and sympathizer,Ethel Douglas Hume, to put togethersome notes he had collected as a book thatwas published first in 1923 under the titleBéchamp or Pasteur? A Lost Chapter in theHistory of Biologyand pours scorn onPasteur ’s efforts and accuses him ofplagiarism and fabrication.16The bookwas republished in 1932 and has gonethrough numerous subsequent editionsand modifications of title (more recentlybeing attributed to Douglas Hume!).cIt isof course increasingly true that muchhuman disease and suffering cannot beattributed to infection but stems fromchanges within us, but in this the micro-zymes do not have a place.With a medical colleague, Alfred Estor,Béchamp observed granulations in cells(they mainly studied liver of differentspecies).21In the physiological state thesegranules, which they considered to bemicrozymes, are spherical, but outsidethe cell they develop into bead-like elon-gated structures, eventually recognizableas bacteria. From observations of bacteriain blood, they conclude that bacteria, farfrom being the cause of illness, are, to thecontrary, the result.Thus, in death the microzymes becomebacteria, eventually reducing the cells ofhigher organisms to dust, and then revert-cThe most recent edition I have been able to track down ispublished byHealth Research,in 2003 (ISBN-100787311286).There are also items on the Web.ing to microzymes. Airborne germs arisefrom microzymes in dead plant andanimal life. Béchamp writes: ‘The micro-zyme is at the beginning and at the end ofevery cell organization. It is the funda-mental anatomical element by which thecellules, the tissues, the organism, thewhole of an organism are constitutedliving.’12CodaIt seems likely that, in the 1850s and1860s, Béchamp and Pasteur were inde-pendently making similar discoveries—anot unknown phenomenon in science.Accusations of plagiarism are thereforeprobably not justified. Pasteur withoutquestion was aggressive and intolerant ofopposition and treated Béchamp shabbily,but Béchamp led himself into a theory ofsuch generality that was both its strengthand its weakness—it could be used toexplain too much, but did not lend itself toexperimental testing. In a France increas-ingly idolizing Pasteur and his memory,Béchamp was bound to become increas-ingly ignored. Only Miss Hume16and fol-lowers, for their own reasons, have kepthis name alive.1. Pasteur L. (1857). Mémoire sur la fermentationappelée lactique.Compt. Rend.45,913–916.2. Pasteur L. (1856). Isomorphisme entre des corpsisomères, les uns actifs, les autres inactifs sur lalumière polarisée.Compt. Rend.43,1259–1264.3. Pasteur L. (1848). Mémoire sur la relation qui peutexister entre la forme cristalline et la compositionchimique, et sur la cause de la polarisationrotatoire.Compt. Rend.26,535–538.4. Pasteur L. (1857). Mémoire sur la fermentationalcoolique.Compt. Rend.45,1032–1036.5. Pasteur L. (1858). Nouveaux faits concernantl’histoire de la fermentation alcoolique.Compt.Rend.47,1011–1013.6. Buchner E. (1897). Alcoholische Gährung ohneHefezellen.Ber. Dt. Chem. Ges.30,117–124.7. Béchamp A. (1855). Note sur l’influence que l’eaupure et certaines dissolutions salines exercent surle sucre de canne.Compt. Rend.40,436–438.8. Béchamp A. (1858). De l’influence que l’eau purou chargée de diverse sels exerce à froid sur thesucre de canne.Compt. Rend.46,44–47.9. Meeting report (1862).Revues des Sociétés desSavantesI,81.10. Béchamp A. (1864). Sur la fermentation alcoo-lique.Compt. Rend.58,601–605.11. Béchamp A. (1872). Seconde observation surquelques communications récentes de M. Pasteur,notamment sur la théorie de la fermentationalcoolique.Compt. Rend.75,1519–1523.12. Béchamp A. (1883).Les Microzymas: L’hétérogénie,l’histogénie, la physiologie et la pathologie.LibrairieJ.-B. Baillière, Paris.13. Report of International Medical Congress (1881).The Times(London), 8 August, p. 6.14. Report of International Medical Congress (1881).Br. Med. J.2,547–548.15. Pasteur L. (1876).Études sur la Bière.Gautier-Villars,Paris.16. Hume E.D. (1923).Béchamp or Pasteur? A lostchapter in the history of biology.Covici-McGee,Chicago.17. Béchamp A. (1858). De l’influence que l’eau pure,ou chargée de divers sels, exerce, à froide, sur lesucre de canne.Ann. Chim.3rd ser., 54, 28–42.18. Béchamp A. (1867). Lettre adressée àM. lePrésident,au sujet de la communication faite parM. Pasteurle 29 avril dernier.Compt. Rend.64,1042–1043.19. Béchamp A. (1903).Louis Pasteur: ses plagiatschimicophysiologiques et medicaux.Chez l’auteur,Paris.20. Béchamp A. (1866). Du rôle de la craie dans lesfermentations butyrique et lactique, et desorganismes actuellement vivants qu’elle contient.Compt. Rend.63,451–455.21. Béchamp A. and Estor A. (1868). De l’origine et dudéveloppement des bactéries.Compt. Rend.66,859–863.22. Findlay A. (1965).A Hundred Years of Chemistry,3rdedn, p. 47. Wiley, New York.
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