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Carbon Catabolite Repression and Global Control of The Carbon Catabolite Repression and Global Control ofth e Carbohydrate Metabolism in Lactococcus lactis Evert J. Luesink Promotor: dr.W.M .d eVo s hoogleraar ind emicrobiologi e Co-promotor: dr. O.P. Kuipers sectieleider Microbial Ingredients, NIZO,Ed e Carbon Catabolite Repression andGloba l Control ofth eCarbohydrat e Metabolism in Lactococcus lactis EvertJ . Luesink Proefschrift terverkrijgin gva nd egraa dva ndocto r opgeza gva nd erecto rmagnificu s vand e LandbouwuniversiteitWageningen , dr.CM .Karssen , inhe topenbaa r teverdedige n opmaanda g 14decembe r199 8 des namiddagst e 13.30uu ri nd eAula . Everythingshould be made assimple aspossible, butnot simpler. Albert Einstein. AanIs a Aanmij nouder s ISBN90-5485-931- 8 Omslag: I.Lalande-Luesin k Druk:Ponse n& Looije nBV , Wageningen. BIBLIOTHEEK LANDBOUWUNIVERSITEIT WAGENINGEN -M.ZVi? Stellingen 1 Ye en cowerker s gaan in hunexperimente n ten onrechte uitva nd e afwezigheid van HPr moleculenterwij l enzyme I,da t inee n grote ondermaat ten opzichte vanHP r aanwezig is,veronderstel d wordt in mime hoeveelheden aanwezig te zijn. Ye,J .J. ,J . Reizer,an dM .H .Saie rJr . 1994.Regulatio no f2-deoxyglucos ephosphat eaccumulatio n inLactococcus lactis vesicle sb ymetabolite-activated ,ATP-dependen tphosphorylatio no fserine-4 6i n HPro fth ephosphotransferas e system.Microbiolog y 140:3421-3429 Kohlbrecher, D., R. Eiserman,an dW .Hengstenberg . 1992.Staphylococca l phosphoenolpyruvate- dependent phosphotransferase system: molecular cloning and nucleotide sequence of the Staphylococcuscarnosus ptsl gene :expressio nan dcomplementatio nstudie so fth eproduct . J. Bacterid.174:2208-2214 . 2 Hetobservere n van cAMP-afhankelijke kataboliet repressie inGram-positiev e bacterien berustwaarschijnlij k eerder opee ngedege n literatuurkennis van de wetenschapper dan opee ndaadwerkelij k bestaand fenomeen. Garro,M.S. ,d eValdez ,G.F. ,G .Oliver ,an dG.S .d eGiori .1996 .Influenc eo fcarbohydrate so nth e a-galactosidaseactivit yi nLactobacillus fermentum. Curr.Microbiol .33:302-305 . Poolman,B. ,A.J .Driessen ,an dW.N .Konings .1987 .Regulatio no farginine-ornithin eexchang e andth earginin edeiminas epathwa yi nStreptococcus lactis. J.Bacterid .169:5597-5604 . Saier,M.H .Jr. ,S .Chauvaux ,J . Deutscher,J . Reizer,an dJ.J .Ye . 1995.Protei nphosphorylatio n andregulatio no fcarbo nmetabolis mi nGram-negativ eversu sGram-positiv ebacteria .Trend s BiochemSci .20:267-271 . 3 Degroott e van het SacR eiwitzoal s beschreven door Siegers en Entian bewijst dat de interpretatie van sequentiedata minstensz o belangrijk isal sd e presentatie ervan. Siegers,K. ,an dK .D .Entian .1995 .Gene sinvolve di nimmunit yt oth elantibioti c nisinproduce d by Lactococcuslactis. Appl.Environ .Microbiol . 61:1082-1089. Ditproefschrift , Hoofdstuk2 . 4 Glucoserepressie ismee rda n katabolietrepressie. Ditproefschrift . 5 Hetfei tda td emetereologi ezic hal senig ewetenscha p serieus aan voorspellingen waagt kan gezienworde n als bewijs voor het belang vanee ngoed e communicatie tussen wetenschap en publiek. 6 Ter bevordering vand e reproduceerbaarheid is het,zeke r binnend eexact e wetenschap, aan tebevele n niet mettwe e matent e meten. 7 De nieuwe ISOcertificate n vand e keizerdrage n er inel k gevalto e bijda t de verleners vandez e certificaten erwar m aangekleed bijlopen . 8 Eengoed ediscussie ,voor ,tijden s en naee nwetenschappelij k experiment, is het zout ind epap . 9 Deefficienti e vantelewerke n isomgekeer devenredi g metd e afstand die overbrugd moetworde ntijden s de communicatietusse n dewerkgeve r end e werknemer. 10Ee n betere harmonisatieva n hetgeschiedenisonderwij s ind e verschillende Europese landen zouee n grotere bijdrage leveren aan deonderling e integratie dan de invoering vanee n gemeenschappelijke munt,tege n eenfracti e vand ekosten . Stellingen behorende bijhe t proefschrift "Carbon Catabolite Repression and Global Control ofth e Carbohydrate Metabolism in Lactococcus lactis". EvertLuesink, Wageningen,14 december 1998. Voorwoord Na vier jaar is het moment aangebroken om even stil te staan bij de afgelopen periode op het NIZO, en de mensen die hebben bijgedragen aan dit proefschrift te bedanken. Allereerst wil ik mijn promoter Willem de Vos bedanken.Willem , bedankt voor je kritische ondersteuning van het onderzoek, jouw niet aflatende stroom van sceptische vragen en suggesties hebben een zeer grote invloed gehad op het uiteindelijke resultaat. Mijn co-promoter Oscar Kuipers wil ik bedanken voor zijn interesse in hetwer k enzij n bereidheid tot hetdiscussiere n over mogeiijke modellen. De collega's uit de catacomben van het NIZO wil ik bedanken voor de plezierige samenwerking en de gezellige sfeer zowel binnen als buiten het lab. Ger, Ingrid, Joey, Saskia, Michiel, Pascalle, Iris, Ingeborg, Patrick, Hans, Roger, en alle tijdelijke medewerkerse n studenten,allemaa lva n harte bedankt. De medebewoners van het wissellab verdienen een aparte vermelding: Marke Beerthuyzen, Cindy van Kraay, Jeroen Wouters en BenoTt Grossiord waren gedurende deze periode een belangrijke steun zowel tijdens hetwer k als daarbuiten. Marke, bedankt voor je antwoorden op mijn vragen en voor je hulp de afgelopen jaren. Cindy en Jeroen,julli e waren slechts een korte periode bij de genetica groep (Hmmm... ), maar tech had ik de indruk datjulli e veel langer aanwezig waren. In elk geval wil ik jullie bedanken voor de vrolijke sfeer tijdens het werk. BenoTt, Iwan t to thank you for the discussions we had about catabolite repression and the carbohydrate metabolism in L. lactis.Furthermore , Iwoul d like to thank you for your help in understanding the French and the French language and Ia mgla d that Icoul d teach you some new Frenchword s (C'est moiquelqu e chose!). Richard, ondanks het feit dat we vaak niet begrepen werden (ik denk hier bijvoorbeeld aan "Het Zustertje" of "Het Dansende Meisje"), zijn we de laatste jaren op het NIZO een flink aantal levenswijsheden op het spoor gekomen en ik hoop dat we deze zoektocht naar de diepere betekenis van het leven nog lang kunnen voortzetten. Ikwi l de studenten Hans Paalman, Christel Beumer en Rene van Herpen, die in het kader van een stage en of een afstudeervak meegewerkt hebben aan het in dit proefschrift beschreven werk, van harte bedanken voor nun inzet. Daarnaast wil ik alle andere collega's van het NIZO, in het bijzonder de voormalige afdelingen Biophysische Chemie en Microbiologie bedanken voor de fijne werksfeer op het instituut, die in een belangrijke mate heeft bijgedragen aan het tot standkomen van dit proefschrift. Boyendien een woord van dank aan het NIZO en de Europese Unie voor hetmogelij k makenva ndi t promotieonderzoek. Mijn ouderswi l ik bedanken voor hunondersteunin g deafgelope njaren . Isa, mem es i aucun mot nesuffi t adecrir e tout ce que tu representes pour moi,j e tiens at e remercier pourt a patience,te sencouragement s etto n amour. Evert CONTENTS Chapter 1 General Introduction 1 Chapter 2 Characterization of the divergent sacBKan d sacAR operons 25 involved insucros e utilization by Lactococcus lactis. Chapter 3 Immunological crossreactivity toth e catabolite control protein 45 CcpA from Bacillus megaterium is found in many Gram- positive bacteria. Chapter 4 Transcriptional activation of the glycolytic las operon and 53 catabolite repression of the gal operon in Lactococcus lactis are mediated byth e catabolite control protein CcpA. Chapter 5 Molecular characterization of the Lactococcus lactis ptsHI 75 operon and analysis ofth e regulatory role ofHPr . Chapter 6 Summary and concluding remarks 97 Chapter 7 Nederlandstalige samenvatting 109 Appendix 120 Curriculum vitae 134 Listo f publications 135 CHAPTER 1 General Introduction Parto fthi s chapter was published inL eLai t 78:69-76 (1998) General introduction Lactic acid bacteria. Lactic acid bacteria represent a group of Gram-positive bacteria comprising the genera Lactococcus, Lactobacillus,Leuconostoc an d Streptococcus. These bacteria arewidel y used in dairy fermentations where their main function is the conversion of the milk sugar lactose into lactic acid, which conserves the food-product and prevents the growth of pathogenic and spoilage bacteria (Venema et ai, 1996). Furthermore, these bacteria may contribute to the texture of the fermented product by the production of extracellular polysaccharides which enhance the viscosity. Finally, the hydrolysis of the milk protein casein, to peptides and free amino acids followed by their further modifications catalyzed by proteolytic enzymes and amino acid convertases of lactic acid bacteria contribute to the taste and the aroma of the final product. Since industrial dairy fermentations are used on a large scale world­ wide,thei r economic value isconsiderable . Bacteria belonging to the genus Lactococcus lactis are often used in starter cultures for the fermentation of different dairy products e.g. cheese, buttermilk or butter. The two most frequently used subspecies are L. lactis subsp. lactis and L lactis subsp. cremoris that can be distinguished by differences in specific DNA sequences including those encoding 16S rRNA (Godon et ai, 1992). L. lactis is capable ofconvertin g a limited number of mono- and disaccharides to L-lactatevi aa homolacticfermentation . The growth under anaerobic conditions and the absence of cytochromes reduce the possibility to generate energy by the reduction of external electron acceptors and account for the limited metabolic capacities of L. lactis.A s a consequence, L. lactis can only generate energy via either
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