EIBE European Initiative for Biotechnology Education 2000 33UNIT 17: BIOTECHNOLOGY: PAST AND PRESENT

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TEXT AND SCRIPT: STEFANIA UCCELLI, ALESSANDRA CORDA MANNINO, MATTEO MERLISCIENTIFIC ADVICE: ANTONELLA SCATTINA, GIANCARLO DONDO, ANTONIO SEVERI BARGELLESI

DRAWINGS: MATTEO MERLI ENGLISH TEXT: CAROLINE SHEARER

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34 UNIT 17: BIOTECHNOLOGY: PAST AND PRESENT EIBE European Initiative for Biotechnology Education 2000

ITS 10 OCLOCK!! I WANT THAT REPORTON YEAST - GET ALONG TO THE

ADVANCED BIOTECHNOLOGY CENTRENOW!! THEY ARE WAITING FOR YOU.

OK! OK! IM ONMY WAY.

AARGHWHAT A BORE!

HEY -HEY -HEY -HEY -HEY -I HEARD THAT!!I HEARD THAT!!I HEARD THAT!!I HEARD THAT!!I HEARD THAT!!

LATER... YAWN, HERE GOES, I HOPE IM NOTTOO LATE. HUH, WORKING ON A SUNDAYMORNING, I CANT BELIEVE IT! JUST BE-CAUSE MY BOSS WANTS A REPORT ON THEHISTORY OF YEAST BY TOMORROW.

EIBE European Initiative for Biotechnology Education 2000 35UNIT 17: BIOTECHNOLOGY: PAST AND PRESENT

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MAY I COME IN?IS ANYONE

HERE? AT LAST! I WASJUST GIVING UP

HOPE. IM THE ONLYONE TO HAVE

WAITED.

ER... WHOS THAT SPEAKING?

COME ON IN IFYOURE COMING.NOTHING TO BE

AFRAID OF!

COME A BIT CLOSER!LOOK DOWN THE

MICROSCOPE.

ER...WHO AREYOU? WHAT! DONT

YOU KNOW WHOI AM?

HI! I AM SACCHAROMYCES CEREVISIAEOR SACCAROMICIO TO MYFRIENDS, ARENT YOU HERETO INTERVIEW ME?

ER...YES...BUT ITS NOT

QUITE WHAT IEXPECTED....

...A DIRECT INTERVIEW? WHAT BETTER, ASCOOP! I CAN TELL YOU THE WHOLE STORY

OF THE INVISIBLE WORKERS.

UH... OK, FINE, AM I DREAMING? OHWELL, HERE GOES...NOTHING TO LOSE!

RIGHT! ARE YOU SITTING COMFORTABLY? TURNON YOUR TAPE - ITS A LONG STORY STARTINGIN ANCIENT EGYPT.

IN ANCIENTEGYPT!?

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36 UNIT 17: BIOTECHNOLOGY: PAST AND PRESENT EIBE European Initiative for Biotechnology Education 2000

AT THE TIME OF PHAROAH RAMESES, THERE WAS A FAMOUSBAKERY WHERE MY ANCESTORS THE ABRACADABRAS WERE

REALLY WIZZ AT THEIR JOB.

...WIZZ? YES - WIZARD. THE EGYPTIANSTHOUGHT THAT MAGIC MADE

THE DOUGH RISE!

FOR A LONG TIME FERMENTATION WAS BELIEVEDTO BE DIVINE INTERVENTION AND SO WAS NOTINVESTIGATED ... NO ONE KNEW IT WAS THESKILLS OF MY ANCESTORS THAT MADE THE BREADRISE!

OH REALLY! AND HOW DIDYOUR ANCESTORS MAKE THE

BREAD RISE?

JUST LIKE I DO, LET ME EXPLAIN. WHEN THE DOUGH WAS LEFT TOREST, MY ANCESTORS LIVED OFF THE STARCH IN THE FLOUR ANDMULTIPLIED FAST! THE BIOCHEMICAL PROCESS THEY MASTERMINDED -CALLED FERMENTATION - HAD THE EFFECT OF MAKING THE DOUGHRISE....

EIBE European Initiative for Biotechnology Education 2000 37UNIT 17: BIOTECHNOLOGY: PAST AND PRESENT

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LIKE MY ANCESTORS, MY TALENTED FAMILY PRODUCE ENZYMES WHICH CAN BREAK DOWNTHE STARCH IN FLOUR TO THE SUGARS MALTOSE AND THEN GLUCOSE - WHICH WE CANLIVE OFF. BUT OUR REAL TALENT IS TO USE SUGARSTO PRODUCE CARBON DIOXIDE& ALCOHOL!!

TAKE A CLOSE UP LOOKAT A LUMP OF DOUGH ...THE CARBON DIOXIDE

BUBBLES GET TRAPPED INTHE DOUGH. WHEN ITS

BAKED, THE ALCOHOLEVAPORATES BUT THE

CARBON DIOXIDEBUBBLES EXPAND, MAKING

THE BREAD SOFT.

FERMENTATION STARTS SLOWLY, WE NEED TIME TO GET THAT STARCH BROKEN DOWN TO GLUCOSEAND TO GET GOING ON SOME SERIOUS REPRODUCTION SO THAT THERE ARE ENOUGH OF USWORKERS...THEN WE REALLY PICK UP SPEED!

WOW! WHATA STORY.

ENOUGH OFTHAT, NOW MEETSOME MORE OFMY ANCESTORS

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38 UNIT 17: BIOTECHNOLOGY: PAST AND PRESENT EIBE European Initiative for Biotechnology Education 2000

SOME OF MY COUSINS - THE LEAVENERSWORKED WITH THE HEBREWS

THEY ALWAYS WENT RATHER HUNGRY OVERPASSOVER TIME, POOR THINGS, WHEN THEHEBREWS MADE UNLEAVENEDBREAD...

UNLEAVENED BREAD?YEAH, A REMINDER

OF THE RUSHEDPACKING WHEN THEYHAD TO FLEE EGYPT

THE GREEKS, ON THEOTHER HAND, REALLYGOT BREADMAKING

ORGANISED - THEY HADCOMMERCIAL BAKERIES

AROUND 400BC. MYCOUSINS THE RISERSHAD A HARD JOB KEEP-

ING THEM HAPPY....

...THE RISERS WERE EXPECTED TO WORK ALL NIGHT LONGMAKING MANY DIFFERENT SORTS OF BREAD... NOT THAT

ANYONE RECOGNISED THEM FOR THEIR TALENTS!

EIBE European Initiative for Biotechnology Education 2000 39UNIT 17: BIOTECHNOLOGY: PAST AND PRESENT

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NOW FOR THEROMANS!

CRIPES!THERES MORE

TO BREADMAKING THAN I

THOUGHT!!

IN ROMAN TIMES THE SKILLS OF MY COUSINS THEFERMENTERS LED TO CLASSY WHITE BREAD FOR THE

RICH AND POWERFUL...

A ROMAN BANQUET

...BUT NOT EVERYONE WAS SO LUCKY! THEREWERE DIFFERENT BREADS FOR ATHLETES, FORPEASANTS, FOR SLAVES...

...AND EVEN FREE BREAD AT GAMES IN THE ROMANCIRCUSES! BUT IT WAS STILL THOUGHT THATTHE RISING OF THE DOUGH WAS DUE TO SOMESUPERNATURAL PHENOMENON!!HONESTLY!!

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40 UNIT 17: BIOTECHNOLOGY: PAST AND PRESENT EIBE European Initiative for Biotechnology Education 2000

BREAD MAKINGDIDNT CHANGE MUCH

UNTIL ONE DAY......WHAT?ONE DAYWHAT?

HANG ON AHANG ON AHANG ON AHANG ON AHANG ON AMINUTE!!MINUTE!!MINUTE!!MINUTE!!MINUTE!!

DONT INTERRUPT ME!

OOER!SORRY.

WELL, WHERE WAS I? AAHUH. UNTIL ONE DAY IN 1673 WHEN A DUTCH CLOTH MERCHANT CALLEDVAN LEEUWENHOEK, A KEEN RESEARCHER IN HIS SPARE TIME AND AN ACE LENS GRINDER, MADE A

MICROSCOPE THAT COULD MAGNIFY 200 TIMES... WELL, THAT MEANT HE COULD SEE LOTS OFTHINGS INVISIBLE TO THE NAKED EYE, AND ONE OF THOSE WAS US - THE YEASTS!!!

HOWEVER, THINGS WERE STILL ABIT MUDDLED AS AT THAT TIME

THEY WERE CONVINCED THATSOME LOWER ORGANISMS...

... LIKE INSECTS AND WORMS COULD ARISE FROM RUBBISHBY SPONTANEOUS GENERATION!

EIBE European Initiative for Biotechnology Education 2000 41UNIT 17: BIOTECHNOLOGY: PAST AND PRESENT

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HANG ON, I DONT WANT TO SPOIL YOURSTORY BUT DID YOU KNOW THAT BY THEN,

IN 1668 ACTUALLY, REDI HAD DEMON-STRATED THAT LARVAE CAME FROM...

...MICROSCOPIC EGGS LAID BY FLIES. LATER OTHERSCONFIRMED THIS, WHICH RATHER UNDERMINED THETHEORY THAT ORGANISMS CAN ORIGINATE FROMDEAD SUBSTANCES.

YES, I KNOW. BUT WHEN MICROBES WEREFIRST DESCRIBED - SOON AFTER REDIS EX-PERIMENTS - MANY RESEARCHERS STILLTHOUGHT THAT THEY MIGHT ARISE FROMDEAD MATTER.

RIGHT, BUT LATER, IN 1765, ANOTHER ITALIAN,SPALLANZANI, MANAGED TO SHOW THAT EVEN

MICROSCOPIC ORGANISMS COUDNT ARISE...

...FROM DEAD MATTER. HE ISOLATED ASINGLE BACTERIUM AND SAW IT DIVIDE

INTO TWO! THE THEORY OF SPONTANEOUSGENERATION WAS FINALLY ZAPPED BY

PASTEUR IN 1862.

AAH YES, PASTEUR... HE ISOLATED YEASTS ANDLEARNT TO GROW THEM IN THE LAB. IT WAS PASTEURWHO APPRECIATED THAT MY ANCESTORS WERE ABLETO CONVERT SUGAR INTO ALCOHOL WITHOUT AIR.

IT WAS A START, ALTHOUGH IT TOOK MORE TIME FORUS TO BE RECOGNISED FOR WHAT WE REALLY ARE...NOBLY DESCENDED FROM THE ASCOMYTES AND CLOSERELATIVES OF SUCHDELICACIES ASTRUFFLES ANDMUSHROOMS.

THE FRENCHMAN, CAGNIARD DE LA TOUR, APHYSISIST OF ALL THINGS, STUDIED USVERY CLOSELY INDEED... IN MICROSCPICDETAIL... VERY ATTENTIVELY...

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42 UNIT 17: BIOTECHNOLOGY: PAST AND PRESENT EIBE European Initiative for Biotechnology Education 2000

...WATCHING EVERYTHING... HE EVEN MANAGED TO SEEUS ...AHEM... REPRODUCING!!! IN 1835 HE FINALLY DE-CIDED THAT WE WERE LIVING - THEDARK SPOTS ARE ALIVE!

THEN OUR LIVES REALLY WENTPUBLIC - THERE WAS ALWAYS

SOMEONE WATCHING US!!

IN 1897 WE WERE GROUND UP WITH FINE SAND BY BUCHNER, A KEEN GERMAN CHEMIST. THAT PARTICULARSACRIFICE ENABLED BUCHNER TO EXTRACT A JUICE WHICH HAD SOME OF OUR CATALYTIC ABILITIES - ITWON HIM THE NOBEL PRIZE FOR CHEMISTRY. BUT AT LEAST SOME OF OUR TALENTS WERE BEGINNING TOBE RECOGNISED.

CHATTERINGAGAIN?

HI! WELCOMEBACK.

OH! ER.. CANYOU HEAR HIM

TOO?

YUP, DONT FORGET ITSA CARTOON! HAS HE

TOLD YOU WHAT WE CANDO WITH YEASTS

NOWADAYS?

EIBE European Initiative for Biotechnology Education 2000 43UNIT 17: BIOTECHNOLOGY: PAST AND PRESENT

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DETAILED STUDIES HAVEMADE US REALISE THAT

THEY HAVE EXTRA-ORDINARY ABILITIES...

...AND MADE US WONDERHOW TO EXPLOITTHOSE ABILITIES!

YES, THEY DISCOVERED THAT IF THEYGIVE US GOOD CONDITIONS - PLENTY OF

SUGAR AND OXYGEN...

...WE CAN REPRODUCE AND WORK FAST - ON ANINDUSTRIAL SCALE- AND THAT THE BEST OF

US, THE REALLY SKILLED WORKERS, CANPRODUCE A VERY FINE BREAD!

HOW DO YOUSELECT THE

BEST?

NO PROBLEM. WE ISOLATENATURAL YEAST STRAINS - FROMGRAPES OR BREWING - AND CHECK

OUT THEIR ABILITIES.

SOME OF US GIVE BREAD AGREAT TASTE, SOME MAKE MORE

CARBON DIOXIDE OR LESSETHANOL, SOME ARE MORERESISTANT TO FREEZING...

HEY! WHOSTALKING HERE?

AS I WAS SAYING, WE SELECTSTRAINS WITH THE CHOSEN

TALENTS...

...AND IN THE LAB WEGROW THE CHOSEN

STRAINS.SO HOWDO YOU

DO THAT?

WELL, TAKE THESE TWO - A.SMELLY AND B.FIZZY - EACH IS GROWN INA PETRI DISH ON A SPECIAL (STARVATION) MEDIUM TO ENCOURAGEMEIOTIC DIVISION...

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44 UNIT 17: BIOTECHNOLOGY: PAST AND PRESENT EIBE European Initiative for Biotechnology Education 2000

OOER! WHATS SO SPECIAL ABOUTTHIS MEIOW.... DIVISION?

MEIOTIC,YOU SAY

MEIOTIC...

ITS SPECIAL BECAUSE EACH CELL FORMS AN ASCUS - A BAG OF 4HAPLOID SPORES, EACH WITH ONLY HALF THE GENETIC MATERIAL.

GIVEN HALF DECENTCONDITIONS WE WOULDNORMALLY REPRODUCE BY

BUDDING!

TRUST HIM TOCHIP IN!

WHAT NEXT?THE ASCUS...??

WE CAN BREAK ITS OUTER MEMBRANEWITH SPECIAL ENZYMES AND RELEASETHE SPORES.

WE THEN FEED THEM UP ON A GOOD NUTRIENTMEDIUM,SO EACH SPORE GROWS INTO A VISIBLE COLONY WHICHWE CAN CHECK OUT.

NOW WE TAKE A SMELLY TYPE COLONY ANDMIX IT IN CULTURE MEDIUM WITH A FIZZYTYPE COLONY! AND WHAT HAPPENS??...

...SPORES OF OPPOSITEMATING TYPES WILL FUSE...

EIBE European Initiative for Biotechnology Education 2000 45UNIT 17: BIOTECHNOLOGY: PAST AND PRESENT

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...AND ZYGOTES (DESCENDANTS)WILL FORM THAT ARE NEW HYBRIDS

- SMELLY/FIZZYSO?

WE HAVE A STRAINWITH BOTH TALENTS!

ALL THIS JUST FORBETTER BREAD?

JUST!!! JUST!!! JUST!!! JUST!!! JUST!!! SHOW SOMERESPECT FOR TALENT!

SORRY! IDIDNT

MEAN TO....

LET ME SPELL OUT OUR SKILLS FOR YOUAND MAYBE YOU WILL SHOW A LITTLE

MORE RESPECT!

WE ARE THE STAR PLAYERS OF THE BIGBAKERIES - KNOWN BY OUR STAGE NAME:

BAKERS YEAST...

...REALLY WE ARE CARFULLY SELECTED STRAINS OFSACCHAROMYCES CEREVISIAE, GROWN UNDER

SPECIAL CONDITIONS TO GIVE MAXIMUM YIELD. THENWE ARE PRESSED INTO SLABS AND SENT FRESH TO THE

BAKERIES.

WHERE WE ARE WARMLY WELCOMED AND MIXED WITHFLOUR AND WATER INTO DOUGH. HERE WE WORK INTANDEM WITH LACTIC ACIDBACTERIA AND NATURAL YEASTS.

UNFORTUNATELY, WE DONT LIKE TOOMUCH HEAT.... SO THAT WHEN IT COMES

TO THE OVEN....

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46 UNIT 17: BIOTECHNOLOGY: PAST AND PRESENT EIBE European Initiative for Biotechnology Education 2000

...BUT ITS A WORTHWHILESACRIFICE, SUCH EXCELLENT

BREAD!

SNIFF... REALHEROES!!

LATER...THANK YOU. WHAT

AN INCREDIBLEDAY!

THATS OK,COME AND SEE

US AGAINSOMETIME.

THANK YOUTOO!

FROTHY FERMENTATIONS!OOPS, I MEAN

RICH REPORTING

THE NEXT DAY... HMMPH! VERY GOOD, MUCH BETTER THAT IEXPECTED! WHO TOLD YOU ALL THIS?

OH! JUST - NO- NOTJUSTJUSTJUSTJUSTJUST!! A TALENTEDINVISIBLE FRIEND.