KIM GREW UP IN MOSCOW
AND APPARENTLY MET SOME
MEMBERS OF OUR AUDIENCE
AT A MUCH YOUNGER AGE
THERE, OBTAINED HIS
PHD IN CHEMISTRY AT
MOSCOW UNIVERSITY.
HE'S BEEN AT
NORTHEASTERN UNIVERSITY
IN BOSTON SINCE 2001
WHERE HE'S NOW THE
DIRECTOR OF
ANTI-MICROBIAL DISCOVERY
CENTER AND A UNIVERSITY
DISTINGUISHED PROFESSOR.
SO, AS MOST OF YOU
PROBABLY KNOW,
INCREASING THE
RESISTANCE OF BACTERIAL
PATHOGEMS HAS BEEN ON THE
FRONT PAGE OF JOURNALS
AND EVERYBODY'S
ATTENTION.
WE'RE FORTUNATE TO HAVE
DR. LEWIS HERE TODAY TO
TELL US ABOUT HIS WORK
BECAUSE HE'S BEEN AT
THIS FOREFRONT OF
ATTACKING THAT PROBLEM.
I THINK I FIRST BECAME
AWARE OF HIS WORK AND
HIS INTERESTS WHEN HE
STARTED TALKING ABOUT
PERSISTERS.
A SMALL POPULATION OF
CELLS ARE NOT KILLED BY
ANTIBIOTICKIC TREATMENT
BUT REMAIN READY TO GROW
OF THEY GET THE CHANCE
AND REESTABLISHING INFECTION
WE HAVE A SECOND TALK
TOMORROW AT 11:00 A.M.
IN BUILDING 37 TOMORROW
MORNING IN THE SIXTH
FLOOR CONFERENCE ROOM.
IF YOU NEED MORE
INFORMATION ABOUT WHERE
AND WHAT THAT IS, LET ME
KNOW.
THE TITLE 
IS CHANGES IN ENERGY
LEVELS PRODUCED DRUG
TOLERANT PERSISTENT
CELLS.
TODAY'S TALK, HE WILL BE
DISCUSSING HIS EXCITING
WORK ON THE WORK FOR
NOVEL ANTIBIOTICS AND
DEVELOPING INTERESTING
TO GROWING UNCULTURAL
BACTERIA AND THE TITLE
TO THE TALK TO ANTI-
MICROBIAL DARK
MATTER.
PLEASE US KIM LEWIS TO
THE STAGE.
>> THANK YOU VERY MUCH,
SUSAN, FOR A KIND
INTRODUCTION AND THANK
YOU FOR THE INVITATION
TO THIS REALLY GREAT
PLACE.
I GET TO SEE IT FROM THE
OTHER SIDE WHICH IS ALSO
A PLEASURE.
SO WHAT I WILL TELL YOU
ABOUT TODAY IS SOME OF
OUR BASIC SCIENCE AND
HOW THAT INFORMS OUR
DRUG DISCOVERY EFFORTS,
AND I WILL START WITH
THIS SORT OF A TEXTBOOK
PRESENTATION OF
BACTERIAL RESISTANCE.
WHAT YOU WILL SEE HERE
IS THERE ARE LOTS OF
DECREASED MECHANISMS, OR
TARGET MODIFICATION.
AND REALLY EACH AND
EVERY LOGICAL
POSSIBILITY HAS BEEN
REALIZED IN NATURE AND
IT'S BECAUSE OF THIS
PLURALLALITY OF
MECHANISMS.
WE FIND OURSELVES IN THE
ANTI-MICROBIAL
RESISTANCE CRISIS THAT
SUSAN MENTIONED.
APART FROM JUST THE
THREAT OF INFECTIOUS
DISEASES, PER SAY, ONE
OF THE THINGS THAT'S
BECOMING INCREASINGLY
CLEAR AND I'M SURE THAT
EXPERIENCED A NUMBER OF
CASES WITH RESISTENT NOT
SO LONG AGO.
WITHOUT DEFECTIVE
ANTIBIOTICS WE DO NOT
HAVE THE ENTERPRISE OF
MEDICINE THAT WE ARE
USED TO HAVING, SO YOU
CANNOT DO CHEMOTHERAPY
OR SURGERY IF YOU DON'T
HAVE EFFECTIVE
ANTIBIOTICS.
BUT THIS PROBLEM IS
COMPOUNDED BY ANOTHER
PHENOMENON WHICH IS
RELATED TO CHRONIC
INFECTIONS.
ANOTHER WAY THAT
BACTERIA USED TO AVOID
BEING KILLED BY
ANTIBIOTICS AND IT COMES
BY THIS PARADOX OF
CHRONIC INFECTIONS.
ANTIBIOTICS ARE
INFECTIVE AGAINST
ANTIBIOTIC SUS
SUSCEPTIBLE PATHOGENS.
THESE CHRONIC INFECTIONS
OFTEN ASSOCIATE WITH --
AND THERE'S A LONG LIST
OF THEM, TUBERCULOSIS,
AND ONE COMMONALITY
AMONG THOSE TWO IS THE
FACT THAT THE IMMUNE
SYSTEM IS NOT VERY
EFFICIENT IN ATTACKING
THE PATHOGEN.
THEN THE PATHOGEN WHICH
IS OTHERWISE SUSCEPTIBLE
TO TESTS ON A PETRIE
DISH, THAT SAME
ANTIBIOTIC IS .
WE FOUND THIS PRETTY
SIMPLE KILLING
PHENOMENON.
YOU SEE THAT THE BULK OF
THE CELLS ARE EASILY
KILLED, NOTHING SPECIAL
ABOUT THEM.
THEN YOU HIT UPON THE
POPULATION OF CELLS THAT
DO NOT DIE.
SO THAT SEEMS TO BE THE
CULPRIT.
THIS CULPRIT, OUR
PERSISTER CELLS
DISCOVERED ORIGINALLY IN
1934 BY JOSEPH BIGGER
WHO WAS UNABLE TO
CULTURE A STAPH WITH
PENICILLIN.
HE WAS VERY FRUSTRATED
HE COULD NOT DO THAT.
HE PUBLISHED A MARYP AND
THAT PAPER WAS LARGELY
FORGOTTEN FOR A COUPLE
OF DECADES.
IF YOU WILL REDISCOVER
PERSTERS AND REALIZE
THAT IS VERY IMPORTANT,
PROBABLY VERY IMPORTANT
MEDICALLY, AND SO WE
WANTED TO OF COURSE
FIGURE OUT WHAT IS IT
THAT MAKES THESE CELLS
ESSENTIALLY INVULNERABLE
TO ANTIBIOTICS.
NOW TODAY I WILL GIVE
YOU SOME HIGHLIGHTS OF
OUR WORK IN THIS FIELD.
I WILL TALK IN MUCH MORE
DETAIL TOMORROW AND
TODAY I WILL GIVE YOU
SUFFICIENT BACKGROUND TO
THEM AND EXPLAIN WHAT
WE'RE DOING.
OKAY.
SO FIRST OF ALL, WE
WANTED TO KNOW IN
PRINCIPAL WHAT IS IT
ABOUT THESE CELLS THAT
ALLOWS THEM TO STAY
ALIVE.
WE THOUGHT THAT PERHAPS
THEY ARE DORMANT BECAUSE
THEY NEEDED TO GROW NOR
DIE IN THE PRESENT OF
ANTIBIOTIC.
SO HERE'S OUR VIEW OF
THESE TWO FACES OF
THREAT.
THESE ARE RESISTANCE
MECHANISMS.
ALL OF THEM DO
ESSENTIALLY THE SAME
THING, THEY PREVENT FROM
BINDING TO THE TARGET.
TOLERANCE WHICH PERSTERS
EXHIBIT, WE NEED TO
APPRECIATE KILL NOT BY
INHIBIT
INHIBITING.
THAT IS WHAT KILLS THE
CELL, NOT BECAUSE
STOPPED TURNING OUT
PROTEINS.
IF YOUR TARGETS ARE
INACTIVE IN A DORMANT
CELL OR LARGELY
INACTIVE, THEN THE
TARGET IS NOT CORRUPTED
AND THE CELL SURVIVES.
SO THIS SEEMED TO US
LIKE A REASONABLY GOOD
GUESS.
WE LEARNED HOW TO
ISOLATE PERSTERS, GOT
THEIR TRANSCRIPT.
AND WE WERE LOOKING FOR
PROTEINS THAT HAVE THIS
ABILITY TO STOP
IMPORTANT FUNCTIONS IN
THE CELL.
AND ONE OF THE FIRST
THINGS THAT WE NOTICED
WAS THE OVEREXPRESSION
OF A NUMBER OF TOXIN,
ANTI-TOXIN SYMPTOMS.
HAVE BEEN KNOWN FOR A
WHILE AS A MECHANISM OF
MAINTENANCE.
IF THE DAUGHTER CELL BY
ACCIDENT LOSES, THE
ANTI-TOXIN GETS
DEGRADED.
DEPENDING ON WHAT THAT
TARGET IS, KILLS THE
CELL OR CAUSES STATION
IS.
BUT THEN PEOPLE STARTED
SEQUENCING GENOMES AND
COPIOUS NUMBERS.
SO OUR SIMPLE
PROPOSITION WAS THAT
WHAT THESE THINGS DO
INTO THE CHROMOSOME IS
THEY ARE PERSISTER
GENES, AT LEAST SOME OF
THEM.
HERE I'LL GIVE YOU A
SUMMARY GROUPS OVER THE
YEARS, SO WHAT THEY
FOUND IS DIFFERENT
TOXINS, ANTI-TOXINS WILL
SUPPORT PERSIST
INTERESTING MECHANISM
THAT TOBEY IN MY LAB
DISCOVERED WHERE A
STRESS RESPONSE TURNS
DOWN THE B TOXIN WHICH
CAUSES THE DECREASE AND
ATP.
SO THESE ARE HIGHLY
REDUNDANT AND PARALLEL
PATHWAYS OF PERISTER
INFORMATION.
SO ARMED WITH THAT
INFORMATION FROM E.COLI,
WE THEN DECIDED THAT IT
WOULD BE USEFUL TO FIND
OUT WHAT'S HAPPENING IN
OTHER BACTERIA.
AT THAT TIME JOINED MY
LABORATORY AND HE CAME
FROM OUR STAPH LAB SO HE
WANTED TO FIGURE OUT
WHAT'S HAPPENING.
THE FIRST THING THAT HE
DID IS HE KNOCKED OUT
TOXINS, ANTI-TOXINS AND
HAS ONLY THREE, UNLIKE
80 IN TUBERCULOSIS.
SO SO HE KNOCKED OUT
THOSE THREE TOXINS,
ANTI-TOXINS AND ASKED A
SIMPLE QUESTION, IF YOU
EXPOSE THESE GROWING
CELLS, WHAT WILL HAPPEN?
AND ABSOLUTELY NOTHING
HAPPENS.
THERE'S NO DIFFERENCE IN
PERISTER FORMATION IN
THE WILD TYPE OR
KNOCK-OUT.
SAME IN STATIONARY
CULTURE.
SO THAT EXPERIMENT
IMMEDIATELY TOLD US THAT
WHAT WE LEARNED IN THE
PREVIOUS DECADE WAS
COMPLETELY USELESS, AND
WE NEED TO START --
USELESS FOR STAFF.
AND THAT WE NEED TO
START FROM SCRATCH.
WE WENT LOOKING FOR
CLUES, AND ONE OF THE
CLUES THAT WE THOUGHT
WOULD POINT US IN THE
RIGHT DIRECTION WAS THE
FACT THAT STAPH BECOMES
HIGHLY TOLERANT IN
STATIONARY STATES.
SO THEN WE THOUGHT,
WELL, MAYBE PERSISTERS
IN THE GROWING
POPULATION OF STAPH THAT
WENT INTO STATIONARY
EARLY.
HERE'S A SIMPLE TEST HER
THAT PROPOSITION.
WE HAVE A STATIONARY
STATE MARKER CLONED WITH
GFB.
THE CULTURE GROWS FROM
LACK IN STATIONARY
STATE, AND YOU SEE THAT
THERE ARE STATIONARY
CELLS SHOWING UP IN THE
GROWING CULTURE.
IF YOU NOW TAKE THESE
CELLS FROM A GROWING
CULTURE AND SORT THEM
OUT, THOSE THAT ARE
EXPRESSING THE
STATIONARY MARKER AND
EXPOSED TO ANTIBIOTIC,
THOSE ARE THE ONLY CELLS
THAT SURVIVE, SO THOSE
ARE CLEARLY ENRICHED IN
PERSISTERS SO WE HAVE
THIS EFFECT HAPPENING
THAT A GROWING CULTURE
PRODUCES STATIONARY
STATE.
I ALWAYS THOUGHT THESE
ARE TWO DIFFERENTLY
DIFFERENT THINGS.
BY DEFINITION,
STATIONARY ARE NOT
GROWING AND YET THE
GROWING CULTURE PRODUCES
STATIONARY CELLS.
SO WHAT WE'RE THINKING
MAY BE HAPPENING IN
PRODUCING PERSISTER
CELLS IS THAT OF COURSE
WE NOTED THE STATIONARY
CULTURE THE LEVELS OF
ATP ARE CONSIDERABLY
LOWER.
SO WE WERE THINKING THAT
MAYBE PERSTERS ARE CELLS
THAT HAVE LOW LEVELS OF
EXPRESSION OF KEY
ELEMENTS THAT ARE
RESPONSIBLE FOR
ATP PRODUCTION, AND ONE
OF SUCH KEY ELEMENTS IS
ALPHAKETOGLUTER.
TARATE.
IN WHICH IS COATED BY
THE SUCA.
TESTED THIS AND DID THE
VERY SIMPLE EXPERIMENT
WHERE HE HAS A
GFP REPORT OF SUCA
PROMOTERS AND LOOKING AT
THE DISTRIBUTION OF
EXPRESSION OF THIS GENE
IN THE POPULATION.
AND NOW SORTING OUT
CELLS SHOWS THOSE THAT
HAVE LOW LEVELS OF
EXPRESSION OF KETO
GLUTTERATE.
WE'RE PRETTY HAPPY ABOUT
IT BECAUSE THE
ALTERNATIVE WAS THAT
THERE WAS NO MECHANISM
BECAUSE LOTS OF THINGS
ARE GOING TO EFFECT THE
LEVELS OF ATP.
BUT NOW WE KNOW THERE
ARE SOME KEY ELEMENTS
THAT DO THAT.
TOMORROW I'LL TELL ABOUT
YOU SOME ADDITIONAL
MECHANISMS THAT WE
FOUND.
OKAY.
SO HERE'S OUR ADDITIONAL
VIEW OF WHAT'S HAPPENING
WITH PERISTER FORMATION.
I THINK THIS IS A
GENERAL MECHANISM.
SUMMER SPECIFIC AND
PERHAPS SELECTIVE OR
GIVEN BACTERIA.
THIS IS A GENERAL AND
IMPORTANT MECHANISM.
THAT IS THAT ALL OF THE
ANTIBIOTICKIC TARGETS
REQUIRES ATP OF COURSE.
YOU GET CORRUPTION OF
THESE TARGETS BY
ANTIBIOTICS AND DEATH.
AND THEN IF
STATISTICALLY THE LEVEL
OF THE TARGET DECREASES,
YOU GET DORMANT CELLS,
AND YOU GET THE TARGET
SHUTDOWN.
SO THAT VERY SIMPLY
EXPLAINS THE NATURE OF
PERSISTENS.
IT'S PRETTY SIMPLE
EXPLANATION.
I'M GOING TO SAY THAT WE
OVERLOOKED IT.
WE COULD HAVE DISCOVERED
THIS TEN YEARS AGO BUT
WE DIDN'T FOR REASONS I
DON'T UNDERSTAND.
OKAY.
SO APART FROM THAT,
APART FROM THE BASIC
BIOLOGY OF PERSISTERS
THERE'S ANOTHER THING I
WANTED TO TELL YOU
ABOUT, AND THAT IS THE
IMPORTANT QUESTION OF
THE CLINICAL RELEVANT
RESISTANCE OF PER ABC
SISTERS.
SO A FRIEND OF MINE, LOU
RICE, WHO IS HEAD OF
MEDICINE AT BROWN.
HE TOLD ME A NUMBER OF
YEARS AGO THAT IT IS
VERY INTERESTING THAT IF
YOU GUYS ARE DOING WITH
PERSISTER CELLS AND I'M
SURE AMUSING BUT I'M
SURE IT HAS NOTHING TO
DO WITH CLINICAL
MANIFESTATION OF DISEASE
THAT'S ALL THERE IS TO
IT.
SO IT'S DIFFICULT TO
ADDRESS THAT QUESTION.
WE WERE HOPING TO DO AN
EXPERIMENT WHERE WE
ISOLATED PERSISTERS.
WE COULD INTRODUCE THEM
INTO AN ANIMAL AND SEE
IF THAT ANIMAL BECOMES
TOLERANT TO KILLING BY
ANTIBIOTICS.
AT THE MOMENT YOU
INTRODUCE PERSISTERS
INTO AN ANIMAL, THEY
WAKE UP.
THAT WAS QUITE A BIG
PROBLEM FOR US AND FOR
OTHERS IN THE FIELD, AND
THE CLUE TO SOLVING IT
CAME FROM AN EXPERIMENT
THAT WE WERE DOING ON A
COMPLETELY DIFFERENT
SUBJECT.
SO A GRAD STUDENT IN MY
LAP WAS TRYING TO
CATEGORY ALL POTENTIAL
PERSISTER JEANS IN
E.COLI.
THE WAY SHE DID THAT WAS
PERFORM THIS PRETTY
SIMPLE SELECTION
EXPERIMENT WHERE YOU HIT
A CULTURE WITH
ANTIBIOTIC COLLECT
SURVIVING PERSISTERS
REPEATED A COUPLE OF
TIMES, BUT THEN YOU GET
AN ENRICHMENT IN MUTANTS
THAT MAKE MORE
PERSISTENS.
FIGURE OUT WHERE THOSE
POTENTIALLY PERSISTER
GENES ARE.
BUT IF YOU LOOK AT THIS
EXPERIMENTS, WHAT YOU
REALIZE IS THIS IS
EXACTLY WHAT HAPPENS
WHEN WE PEOPLE ARE
TREATED WITH
ANTIBIOTICS.
WE GET PERIODIC HIGH
DOSES OF ANTIBIOTICS AND
BEER PERSISTER IS USEFUL
FOR THE PATHOGEN, THEN
THERE WILL BE SOLUTIONS
IN THE COURSE OF
ANTIBIOTICKIC TREATMENT.
IN THE WAY MILLIONS OF
PEOPLE PARTICIPATED AND
THE EXPERIMENT INCLUDING
PROBABLY EVERYONE
PRESENT IN THIS
AUDIENCE, SO WE SIMPLY
NEED TO LOOK AT THE
RESULTS OF THIS
EXPERIMENT AND DECIDE
WHETHER THEY ARE -- BUT
THAT EXPERIMENT WE DID
BUT FIRST I'LL SHOW YOU
WHAT WE FOUND IN THE
INVITRO EXPERIMENT.
MOST OF THE HIGH
PERSISTER MUTANTS TURN
OUT TO BE MUTANTS IN
DIFFERENT POSITIONS OF
THIS HIPPA TOXINS WHICH
PRO DUNES 100 TO 1,000
TIMES MORE PERSISTERS.
ENORMOUSLY STRONG FHELPO
TYPE.
SO THEN SCREENED A LARGE
COLLECTION OF E.COLI
ISOLATE AND FOUND THAT
IN HALF OF THESE STRAINS
THERE ARE MUTATIONS IN
THE HIPA LOCUSTS.
SO WE WANTED TO
UNDERSTAND
MECHANISMISTICLY.
A STUDY WE DID A NUMBER
OF YEARS AGO, WE WERE
TRYING TO UNDERSTAND
WHAT IS IT THAT HIPA
DOES IN THE CELL TO STOP
IT FROM GROWING.
WE DIDN'T HAVE ANY LEADS
.
AT WHICH POINT I GAVE A
CALL TO EUGENE AND I
ASKED HIM TO TAKE A LOOK
AT HIPA WHICH DOESN'T
LOOK LIKE ANYTHING IN
THE DATA BASE.
SO EUGENE RELUCTANTLY
AGREED TO DO THAT, AFTER
SOME ARM TWISTING.
AND IN THE COUPLE OF
DAYS I WAS SENT AN
E-MAIL WHICH SAID HIPA
WAS A KINASE.
I THOUGHT IT WAS
NONSENSE BECAUSE THERE
ARE NONE OF THOSE IN
BACTERIA.
THE ACTIVE CITES LINED
UP VERY WELL AND WE
FOUND INDEED HIPA IS A
PROTEIN KINASE.
THAT WAS A GOOD CLUE.
SO HIPA IS A PROTEIN
KINASE.
NORMALLY STOPS
TRANSLATION, BUT
NORMALLY IN THE CELL
PRESENT IN THE FORM OF A
DIMER.
SO NORMALLY HIPA IS
LARGELY INAT THIS POINT
ALL IMITATIONS, THEY
HAPPENED AT THE
INTERFACE BETWEEN THESE
DIMEERS.
SO THIS IS THE CASE WHEN
WE CAN UNDERSTAND AND WE
BY THEN ASK THE NUMBER
OF OTHER PATHOGENS.
SO ALL PATHOGENS WE
LOOKED AT AND THESE WITH
TUBERCULOSIS, FROM
CYSTIC FIBROSIS
PATIENTS.
IN THOSE CASES WE FIND
AND CYSTIC FIBROSIS
ABOUT HALF OF ISOLATES.
THERE ARE THESE TWO
PHENOMENON, ONE IS
HERITABLE TOLERANCE.
TO MAKE MATTERS MORE
DIFFICULT FOR US.
THERE WAS A PAPER THAT
JUST CAME OUT IN SCIENCE
THAT SHOWED THAT IN THE
COURSE OF ANTIBIOTIC
TREATMENT, PATHOGEN
FIRST REQUIRES TOLERANCE
MUTATION THAT'S HELP THE
PATHOGENS SURVIVE HIGH
LEVELS OF ANTIBIOTICS
AND ON THAT BASIS
RESISTANCE MUTATIONS ARE
THEN ACQUIRED.
SO THESE TWO MECHANISMLY
DISTINCT, THEY
COLLABORATE, IF YOU
WILL, IN PRODUCING
RESISTENT MUTANTS.
WE NEED TO WORRY ABOUT
BOTH OF THESE PHENOMENON
AND TAKE CARE OF BOTH OF
THEM.
SO WHAT IS IT THAT WE
LEARNED HOW DOES THAT
INFORM OUR DRUG
DISCOVERY EFFORTS.
SO THE PATHWAYS OF
PERSISTER FORMATION IN
THE MODEL E.COLI ARE
MULTIPLE AND REDUNDANT.
MANY OF THESE PERSISTERS
ARE GOING TO BE LOW IN
ATP.
SO IF YOU HAVE REDUNDANT
PATHWAYS, IT MEANS YOU
DON'T HAVE A TARGET.
SO WHAT WE FOUND TELLS
YOU VERY SIMPLY THAT
DRUG DISCOVERY IS RATHER
HOPELESS.
SO FROM THAT UNPROMISING
BASIS, WE WERE THINKING
OF HOW TO GET SOMETHING
THAT'S GOING TO KILL
PERSISTERS.
WHEN MOTHER NATURE COMES
UP WITH A PERFECT
DEFENSE, WHAT WE KNOW IS
THAT IT ALSO PROVIDES A
RESPONSE TO THAT PERFECT
DEFENSE.
AND SO WE WERE WONDERING
IF AMONG NATURAL
PRODUCTS THERE MAY BE
SOMETHING THAT EVOLVED
BECAUSE PRODUCERS VERY
SIMILAR PROBLEM TO US.
THEY WANT TO KILL THEIR
NEIGHBORS INCLUDING
THEIR PERSISTERS.
WHAT WE'RE LOOKING FOR.
WE'RE LOOKING FOR A
COMPOUND THAT WILL IN A
DORMANT TARGET CORRUPT
IT AND KILL THE CELL AND
THAT'S NOT GOING TO
REQUIRE ANY ATP.
THAT'S THE KIND OF A
MAGICAL COMPOUND WE ARE
LOOKING FOR.
ONCE YOU FORMULATE THAT,
THEN INDEED THERE IS A
COMPOUND THAT COMES TO
MIND.
THIS IS A PEPTIDE, A
NATURAL COMPOUND
DISCOVERED BY A GROUP
FROM ELI LILY.
APPARENTLY SOMEONE WAS
VACATIONING IN HAWAII
AND BROUGHT BACK THIS
STRAIN THAT PRODUCE THIS
IS ANTIBIOTIC.
SO LILY HAD A LOOK AT
THIS COMPOUND, AND AT
THE TIME, THIS WAS 195,
EVERYBODY WAS LOOK FOR A
BROAD SPECTRUM
ANTIBIOTICS.
THIS COMPOUND ONLY KILLS
ONE BACTERIA SO LILY
DROPPED IT.
ABOUT 20 YEARS LATER WE
WERE EXPERIENCING AN
EPIDEMIC OF MRSA WHICH
IS STILL ONGOING.
SO A GROUP FROM BAYER
TOOK ANOTHER LOOK AT
THIS COMPOUND, THEY MADE
A MORE ACTIVE DERIVATIVE
AND THEY ALSO DROPPED
THE COMPOUND, BUT BEFORE
DROPPING IT, THEY
DETERMINED THE PRINCIPAL
MECHANISM OF ACTION.
IT IS VERY INTERESTING
THAT THAT'S WHAT
ATTRACTED OUR ATTENTION.
SO THE PROTEASE WILL
NORMALLY RECOGNIZE THE
PEPTIDES.
IN THE PRESENCE OF ADEP,
ATP IS NO LONGER NEEDED.
SO THAT'S THE KEY, OF
COURSE.
THAT'S EXACTLY WHAT THEY
WERE LOOKING FOR.
THEY ARE LOOKING FOR A
FORGET THAT CAN BE
CORRUPTED WITHOUT ANY
REQUIREMENT FOR ATP.
IT SEAMED LIKE A PERFECT
CANDIDATE FOR AN
ANTI-PERSISTENT
COMPOUND, BUT THERE
WASN'T A PROBLEM,
ACTUALLY TWO PROBLEMS.
THESE TWO PAPERS, ONE OF
THEM REPORTED THAT IN
THE PRESENCE OF ADEP,
THEY ARE GETTING OFF
RIBOCELL.
THE OTHER PAPER
IDENTIFIED THE PRIMARY
TARGET.
IT FORMS THE RING AND
THAT IS ALSO ONLY
REQUIRED IN DIVIDING
CELLS, NOT IN DORMANT
CELLS.
SO THE QUESTION IS WHAT
DO YOU DO WHEN FACTS
CLEARLY CONTRADICT YOUR
BEAUTIFUL HYPOTHESIS.
YOU HAVE TWO BASIC
OPTIONS.
ONE IS YOU DECIDE THAT
YOUR HYPOTHESIS IS
WRONG.
OTHER YOU DECIDE THAT
FACTS ARE WRONG.
SO I TOOK A VERY CAREFUL
LOOK AT THESE TWO PAPERS
AND I DIDN'T FIND ANY
PROBLEM WITH THEM.
THEY ARE VERY WELL
EXECUTED STUDIES.
BUT LIKE MOST BIO
CHEMISTRY STUDIES, THEY
ARE PERFORMED ON A
FAIRLY SHORT TIME SPAN
OF ABOUT 10 TO 15
MINUTES.
AND THAT IS AN ISSUE
BECAUSE ANTIBIOTICS ACT
AT A TIME FRAME OF HOURS
AND DAYS, NOT A TIME
FRAME OF MINUTES.
WE DECIDED TO REPEAT
THIS EXPERIMENT AT THE
MORE REALISTIC TIME
FRAME OF 24 HOURS WITH
NONE GROWING STATIONARY
STATE.
AND SO HERE IS THE FULL
PROTEAM AND YOU SEE
MASSIVE DEGRADATION.
IT LOOKS LIKE
ADEP FORCES THE CELL TO
CELL DIGEST.
WE HAD A LOOK AT WHAT
HAPPENS WITH KILLING.
THIS IS A CONTROL.
THESE ARE GROWING.
THAT WAS THE FIRST TIME
WE SAW COMPLETE
STERILIZATION WITH
ANYTHING THAT WAS NOT
BLEACH.
THAT WAS ENCOURAGING AND
THEN WE RECALLED WHY
BAYER DROPPED THE
COMPOUND.
THEY HAD A REASON TO DO
THAT.
YOU GET HIGH PROBABILITY
RESISTENT MUTANTS THAT
ARISE WHEN THERE'S A MAL
MUTATION.
CLIP MUTANTS BECOME
COMPLETELY RESISTENT.
HAS THIS POTENTIAL
SIMPLY COMBINE IT WITH
ANOTHER ANTIBIOTIC.
DOESN'T MATTER WHICH TO
PRESENT THE RISE.
YOU SEE INSTEAD OF AN
ATTEMPT TO KILL,
CONVENTIONAL ANTIBIOTICS
WHICH IS NOT DOING VERY
WELL.
WE ALSO HAVE A LOOK IN
VIETNAM ROW.
ASTRAZENECA DEVELOPED A
MODEL.
HERE YOU SEE THE GROWTH
OF A MASSIVE, INCURABLE
INFECTION.
REGULAR ANTIBIOTICS DO
VERY WELL IN THIS MODEL.
THEY KILL GROWING CELLS
BUT THEN YOU HIT UPON
GROWING PERSTERS AND
THIS IS AN INCURABLE
INFECTION.
AGAIN, IT STERILIZES IN
THIS INFECTION.
THAT GIVES US AN SCAN
PAL OF A COMPOUND THAT
TELLS US IT DID EVOLVE.
THAT WAS THE FIRST BUT
I'M SURE NOT THE LAST,
AND A BIO TECH COMPANY
IS NOW DEVELOPING THIS
INTO A DRUG.
OKAY.
SO IN THE REMAINING
TIME, I WILL TELL YOU
ABOUT OUR EFFORTS TO
DISCOVER NEW ANTIBIOTICS
AND I WILL START WITH
THIS BRIEF INTRODUCTION
INTO WHERE THE FIELD IS
AT THE MOMENT.
SO THE FIELD STARTED
WITH THE FOLDEN ERA WHEN
THE MAIN CLASSES OF TOO
BYTES AND THEY WERE
DISCOVERED.
THIS IS BASED ON AN
EXTREMELY SIMPLE
SCREENING DEVELOPED AND
GOT A NOBLE PRIZE.
THE SCREEN ESSENTIALLY
EMULATES THE ACCIDENTAL
DISCOVERY MADE BY
FLEMMING OR WHEN
FLEMMING FOUND THAT IF
HE HAD A PLATE WITH
STAPH THAT HE WAS
GROWING AND THEN HE GOT
AN ACCIDENTAL
CONTAMINATION.
THERE WAS A ZONE OF
INHIBITION AROUND THAT
CONTAMINANT.
REALIZED THAT YOU CAN
USE THAT SYSTEMATIC
SCREEN AND HE HAD SORT
OF THE GENIUS TO HIT
UPON THE WORLD'S BEST
PRODUCERS OF
ANTIBIOTICS.
HOW HE MANAGED THAT, I
DON'T KNOW.
BUT HE DID.
>> AND SO THIS VERY
SIMPLE SCREEN PRODUCES
THE MAJOR CLASSES OF
ANTIBIOTICS.
THAT GOES ON FOR A WHILE
VERY SUCCESSFULLY, AND
THEN SOMETHING HAPPENS
AROUND THE 1960s AS
THE MECHANISM OF
DISCOVERY IS TURNED OFF.
WE GO INTO THE DARK AGES
AND THEN THERE'S A BIT
OF A RESURGENCE OF
ACTIVITY.
THIS PRIMARILY DEFAULTS
BACK TO THE GOLDEN ERA
MEANING THAT WE'RE
PIPELY TAKEN INITIALLY
FAILED LEADS AND TRYING
TO RESUSCITATE THEM
BECAUSE WE DON'T HAVE --
WE HAVE A PRETTY GOOD
UNDERSTANDING AROUND
WHAT HAPPENED AROUND
1960 AND THAT IS THIS
RESOURCE, THE SOIL,
MICRO
MICROORGANISMS WAS IN
THE WAY LARGELY
OVER-MINED.
BY SCREENING BECAUSE
ONLY 1% OF THEM WILL
GROW.
THE REST OF THE
MICROBIAL DARK MATTER
THAT DOESN'T GROW.
SO WITH MY COLLEAGUE AT
NORTHEASTERN, WE DECIDED
THAT WE WILL TRY TO
REVIVE THE PLATFORM BY
GOING AFTER THIS
MICROBIAL DARK MATTER.
SO THIS IS A SIMPLE
EXPERIMENT THAT IS
SOMETIMES PERFORMED IN
OUR UNDERGRADUATE
LABORATORY WHICH
ILLUSTRATES WHAT
UNCULTURED BACTERIA ARE.
YOU TAKE A SAMPLE FROM
THE ENVIRONMENT LIKE
MARINE SEDIMENT OR SOIL,
AND YOU PUT BUN DROPLET
UNDER THE MICROSCOPE AND
YOU COUNT THE NUMBER OF
CELLS, ANOTHER GOES ON
THE PETRIE DISH, AND YOU
TRY TO FIGURE OUT HOW
MANY COLONIES THESE
CELLS PRODUCE, AND THE
DIFFERENCE IN THE COUNTS
ARE BETWEEN THE NUMBER
OF CELLS AND THE NUMBER
OF COLONIES THAT THEY
PRODUCE IS KNOWN AS THE
GREAT PLATES COUNT
ANOMALY.
THAT'S THE OLDEST
PROBLEM AND DISCOVERED
IN 18 EU8.
SO WINTERBERG THERE'S
BEEN SIGNIFICANT TO PUSH
THE NUMBERS UP AND THAT
DID NOT WORK.
SO WE DECIDED TO DO
SOMETHING DIFFERENT.
INSTEAD OF GROWING
BACTERIA ON THE PETRIE
DISH, GROW THEM WHERE WE
KNOW THEY DO GROW, AND
THAT'S THEIR NATURAL
ENVIRONMENT.
SO WE NEEDED TO COME UP
WITH A GADGET WHERE
BACTERIA CAN GROW IN
PURE CULTURE.
SO HERE YOU TAKE A
SAMPLE FROM MARINE
SEDIMENT, DILUTE IT AND
PLACE BETWEEN THESE TWO
SEMI PERMEABLE AND THIS
CONTRAPTION KNOWN AS A
DEFUSION CHAMBER AND
GOES BACK IN THE NATURAL
ENVIRONMENT.
THEY ARE DRINKING
BACTERIA.
NOT SURPRISING.
LOTS OF STUFF GROWS.
WE GET RECOVERY CLOSE TO
50% IN THE DEFUSION
CHAMBER AS AS OPPOSED TO
THE PETRIE DISH WHICH IS
REALLY LOW.
JUST A PIECE OF PLASTIC
WITH LOTS OF LITTLE
HOLES WHICH YOU DIP IN
THE SUSPENSION OF
BACTERIA.
EACH CAPTURES
APPROXIMATELY ONE CELL.
YOU COVER THIS WITH SEMI
PERMEABLE MEMBRANES AND
YOU GET MICRO COLONIES
IN THESE WELLS.
SO OF COURSE WE WERE
VERY INTERESTED IN
TRYING TO FIGURE OUT WHY
UNCULTURED BACTERIA DO
NOT GROW IN THE PETRIE
DISH.
WHAT IS THE MOLECULAR
MECHANISM?
SO THIS IS FROM MY LAB
AND WE DECIDED TO START
WITH THIS -- WITH BEACH
SAND AS A MODEL WHERE I
SUSPECTED THAT ON THESE
PARTICLES OF SAND WILL
BE MICROORGANISMS.
SO THIS IS WHAT YOU
ACTUALLY WORK ON OF YOU
WALK ON THE BEACH.
YOU WALK ON THIS.
AND THIS IS A -- I DON'T
KNOW WHAT THIS IS BUT IT
LOOKS VERY IMPOSING.
SO THEN WE HAD THE
SIMPLE HYPOTHESIS, AT
LEAST SOME OF THEM DO
NOT GROW BECAUSE THEY
REQUIRE GROWTH FACTORS
FROM THEIR NEIGHBORS.
SO HERE'S A TEST OF THIS
YOU GET A WHOLE ZOO OF
CALL KNEES GROWING.
THEN YOU SAY MAYBE THIS
SMALL TOWN GREW BECAUSE
IT HAPPENED TO BE IN THE
VICINITY OF THIS BIGGER
ONE.
IT WAS RELEASING A
GROWTH FACTOR.
HERE'S A TEST OF THAT,
OF THAT IDEA.
HERE IS A SIMPLE TEST
WHERE YOU PATCH ONE OF
THEM, THE BIGGER ONE AS
IT GROWS IN THE COLONY.
THE OTHER ONE YOU WITH
SPREAD ON A PETRIE DISH
AND IT ONLY GROWS AROUND
THIS BIGGER ONE.
THAT FIRST OF ALL TELLS
YOU THE IDEA IS CORRECT
IN PRINCIPAL AND YOU CAN
PURIFY THE GROWTH FACTOR
BY SIMPLY GROWING UP THE
BACTERIA.
WHAT WE GOT ARE THESE
GROWTH FACTORS.
IF YOU DROP ONE OF THEM
ON A PETRIE DISH, IT
RECAPITULATES THE
HELPING ORGANISM.
SO NORMALLY IRON EXISTS
IN THE FORM OF INSOLUBLE
IRON THREE.
UNCULTURED BACTERIA
INTERESTINGLY LOST THE
ABILITY TO MAKE THEIR
OWN.
THEY COME FROM A
SECONDARY LOSS.
WHY THEY LOSE THEIR
ABILITY TO MAKE AND WITH
IT THEY LOSE THEIR
LIBERTY, THEY ALWAYS
DEPEND ON SOMEONE, THAT
IS A FASCINATING
QUESTION.
BUT NOW THEY HAVE IS TO
STEAL FROM THEIR
NEIGHBORS AND THAT IS
HOW THEY GROW.
SO WE GOT VERY EXCITED
WHEN WE FOUND THIS
BECAUSE I THOUGHT THAT
WE'LL JUST KEEP FINDING
ADDITIONAL GROWTH
FACTORS AND WE'LL CLOSE
THE GAP.
THAT DID NOT HAPPEN.
WE CAN EXPLAIN
APPROXIMATELY 10% OF
UNCULTUREABILITY.
THE NEXT GROWTH FACTOR
GAVE US 1% AND THEN
NOTHING.
I DON'T UNDERSTAND AT
THE MOMENT, BUT I HAVE A
POST DOC IN MY LAB WHO
IS SUPPOSED TO FIND AN
ANSWER TO THIS QUESTION
BY THE END OF THIS YEAR.
[ LAUGHTER ]
>> SO ONE USEFUL THING
THAT WE FOUND IS THAT
ONCE GROWN IN THE
DEFUSION CHAMBERS,
ESPECIALLY IF YOU
REINOCULATE, WITH HIGH
PROBABILITY YOU GET
GROWTH ON A REGULAR
PETRIE DISH.
SO THAT OF COURSE GIVES
YOU NOW ACCESS.
AND SO FAR WE HAVE 2 NEW
COMPOUNDS.
SO I'LL TELL YOU ABOUT
TWO OF THEM.
SO ONE COMPOUND CAME
FROM AN EFFORT TO SOLVE
A VERY TOUGH PROBLEM, A
NATIONAL PRODUCT
DISCOVERY AND THAT'S THE
ENORMOUS BACKGROUND OF
KNOWN COMPOUNDS IN JUNK.
THE WAY CHEMISTS TRY TO
SOLVE THAT PROBLEM IS TO
ASK THE QUESTION WHETHER
YOU HAVE A NEW MONTHLY
CULTURE IN YOUR EXTRACT.
THAT TAKES TIME AND
ENERGY AND THE ANSWER IS
NOT ENTIRELY
SATISFACTORY BECAUSE
YOUR NEW MONTHLY CULTURE
CAN BE A NEW DETERGENT
WHICH IS NOT TERRIBLY
EXCITING.
WE DECIDED ONE WAY TO
SOLVE THAT PROBLEM IS IF
YOU GO AFTER SPECIES OR
GROUP SELECTIVE
COMPOUNDS.
SO NATURE HAS VERY FEW,
IF ANY, COMPOUNDS THAT
HAVE BEEN KNOWN TO HIT A
PARTICULAR GROUP OF
BACTERIA.
LIKE MICHAEL BACTERIA,
FOR EXAMPLE.
SO THEN IF NATURE MAKES
COMPOUNDS, THEY ARE
SPECIFIC, THEN YOU CAN
DO A VERY SIMPLE THING.
YOU TAKE AN EXTRACT AND
YOU'RE LOOKING FOR THIS
PROPER.
YOU'RE LOOKING FOR
INHIBITOR ACTIVITY BUT
NOT AGAINST, FOR
EXAMPLE, IF YOU CAN DO
THAT, THEN CAN YOU
IMMEDIATELY SAY IT
CONTAINS A NEW COMPOUND.
BY DOING THAT WE
DISCOVERED THIS NEW
ANTIBIOTIC.
IT DOESN'T HIT BACTERIA
-- AND IT HAS AN
INTERESTING PROPERTY.
IF YOU LOOK AT
STATIONARY IT'S VERY
TOUGH TO KILL THEM.
THIS IS OUR BEST KILLING
COMPOUND.
WITH SURVIVING PERSTERS.
WE DON'T SEE ANY
INDICATION OF SURVIVING
PERSISTERS.
SO WE GOT VERY
INTERESTED IN THIS COUNT
DOWN IN THE POST DOC.
GOT RESISTENT MUTANTS
FOR.
WE DON'T DO MAPPING
ANYMORE BUT SEQUENCING
SHOW.
THAT IS THE UNIT OF THE
MICRO BACTERIAL CLIP,
WHICH IS FAIRLY SPECIFIC
FOR MICRO BACTERIA.
IT'S ALSO ESSENTIAL.
THAT'S WHY WE GAVE IT
THE SAME LASSOMYCIN
BECAUSE IT LOOKS LIKE A
LASSO.
BUT THEN ALSO THERE'S
STRONG ACTIVATION.
SO IF YOU LOOK AT WHAT
HAPPENS IN WHOLE CELLS,
LASSOMYCIN COLLAPSES
MIEVMENT TB.
WHAT I THINK IS
HAPPENING IS THERE'S
THIS MECHANISM I JUST
TOLD YOU ABOUT WHICH IS
ADP DEPLETION BUT NOT
THE ZERO, AND IT LOOKS
LIKE LASSOMYCIN PUSH
IT'S DOWN AN EXTRA STEP
IN THE ABYSS OF
IRREVERSIBLE DORMANCY.
I THINK IT'S A SNEAKING
MECHANISM, SORT OF
PIGGY-BACKING ON THE
NATURAL WAY TO MAKE
PERSISTERS TO GET RID OF
THEM.
SO IT LOOKS LIKE WE HIT
UPON PERSISTERS.
IT'S THIS PARTICULAR
MACHINE WHICH IS UNDER
ATTACK, SO IN BACTERIAL,
FORCES THE PART OF THIS
MACHINE TO DEGRADE
PROTEINS AND THAT'S HOW
IT KILLS DORMANT CELLS,
WITHOUT ANY REQUIREMENT
FOR ATP.
A VERY DIFFERENT
COMPOUND HITS A
DIFFERENT PART OF THE
SAME MACHINE FORCING IT
TO DIGEST ADP.
OF COURSE THAT DOESN'T
REQUIRE ATP EITHER.
IT JUST MOPS UP WHATEVER
IS IN THE CELL.
WHY THIS PARTICULAR
MACHINE IS UNDER ATTACK
BY COMPLETELY UNRELATED
NATURAL PRODUCTS IS A
FASCINATING QUESTION.
WHILE I'M SURE THAT
THERE ARE OTHER
ANTI-PERSISTER COMPOUNDS
TO BE FOUND, I WILL TELL
YOU ABOUT ANOTHER
COMPOUND THAT WE FOUND
SORT OF RELATED TO THE
GENERAL PROBLEM OF
ANTIBIOTIC RESISTANCE.
THIS WAS DISCOVERED FROM
THIS UNUSUAL CULTURED
BACTERIA.
THAT PARTICULAR GROUP IS
NOT KNOWN TO MAKE
ANTIBIOTICS.
IT IS A GRAM NEGATIVE
BACTERIA.
IT FORMS A NEW GENUS AND
WE HAVE TO GIVE IT A
NAME WHICH IS FREE
EARTH.
THIS NAME IS A MIXTURE
OF GREEK AND LATIN WHICH
YOU'RE NOT SUPPOSED TO
DO WHEN GIVING NAMES TO
CREATURES BUT I FIGURED
THAT NOBODY CARES ABOUT
THESE THING ANYMORE, SO
THIS IS THE NAME OF THE
CREATURE.
IT'S AN INTERESTING
COMPLEX MONTHLY CULTURE,
AND WE CHECKED IT OUT
FOR ACTIVITY AND FOUND
THAT IT HITS ALONG LIST
OF BACTERIA INCLUDING
SOME NASTY PATHOGENS
LIKE MRSA AND
TUBERCULOSIS.
WE TRIED TO GET
RESISTENT MUTANTS TO
THIS COMPOUND AND FAILED
WHICH WAS REALLY
FRUSTRATING BECAUSE
FIRST OF ALL, YOU DO NOT
HAVE AN EASY PATH TO
DETERMINE THE COURSE OF
ACTION BUT MORE
IMPORTANTLY IN OUR
EXPERIENCE, IF YOU HAVE
NO RESISTANCE
DEVELOPMENT, THAT MEANS
THAT YOU DISCOVERED A
NEW DETERGENT.
BUT THEN PARALLEL, WE
WERE -- THIS IS AGAINST
HUMAN CELLS.
THERE'S NO ACTIVITY
AGAINST HUMAN CELLS, SO
THIS WAS VERY TRILLION.
THIS IS THE FIRST TIME
WE SAW A COMPOUND WHERE
THERE'S NO RESISTANCE
DEVELOPMENT, AND SO
SIGHT OF EXISTING.
SO WE EXAMINED IN THE
NUMBER OF ANIMAL MODELS.
I'M NOT GOING TO GO OVER
THIS IN ANY DETAIL JUST
TO TELL YOU SEVERAL
SIMPLE MODELS,
PROTECTION INFECTION AND
MOUSE LUNG IN PNEUMONIA.
THIS IS ALL MOUSE.
SO THAT GAVE US SOME
ADDITIONAL ENCOURAGEMENT
THAT THIS COMPOUND IS
WORTHY OF INVESTIGATING.
SO THEN WE TOOK PARALLEL
INVESTIGATE RESISTANCE
DEVELOPMENT.
THERE'S A PROTOCOL HOW
TO DO IT CORRECTLY, SO
WE DID IT CORRECTLY.
HERE'S A CONTROL.
YOU ADD THE ANTIBIOTIC
AND EACH DAY YOU UP THE
CONCENTRATION.
SO IF YOU HAVE A MUTANT
WITH ANY INCREASE IN
RESISTANCE, EVEN
MINIMAL, IT WILL TAKE
OVER THE POPULATION.
YOU ENCOURAGE RESISTANCE
DEVELOPMENT.
THEN AFTER ABOUT THE
MONTH YOU'RE SUPPOSED TO
DO IT FOR ABOUT A MONTH,
YOU GET AN ENORMOUS
INCREASE IN RESISTANCE,
AND THIS IS PRETTY MUCH
HOW IT WILL LAND
ANTIBIOTICS IN CURRENT
CLINICAL PRACTICE
BEHAVIOR.
WE DID NOT SEE ANY
CHANGES.
SO THAT WAS PRETTY
SURPRISING.
NOW PERFORMED A
SPECIFICITY TEST TO SEE.
THE TEST IS VERY SIMPLE.
YOU SIMPLY FOLLOW THE
RATES OF LABEL
INCORPORATION TO THESE
MAJOR POLY EMERGENCIES
AND THEN THIS EXPERIMENT
TAKES IT BACK AND
SELECTIVELY SO WE KNOW
THIS IS A SOLO ACTING
INHIBITOR.
AND THERE'S NO
RESISTANCE DEVELOPMENT
TO IT SO WE CONCLUDED
THIS COMPOUND DOES NOT
HAVE A PROTEIN TARGET.
PROTEINS WILL ALWAYS
MUTATE.
YOU WILL ALWAYS HAVE A
MUTANT PROTEIN THAT DOES
NOT BIND YOUR
ANTIBIOTIC.
A REALISTIC TARGET WHICH
IS NOT PROTEIN.
SO WE TARGETED WITH A
SIMPLE TEST.
WE HAD GROWING STAFF OR
I COULDN'T SAY WHICH IS
NOT GROWING IN THE
PRESENCE.
IF YOU ADD LIPID, YOU
RESTORE GROWTH.
IF YOU'RE COLLABORATING
WITH TANJA SCHNEIDER
WHERE YOU CAN ISOLATE
LIPID TWO AND SEE IT
LATER, BUT YOU CAN NO
LONGER EXTRACT LIPID TWO
FROM SOLUTION.
SO USING THAT METHOD,
THEN ADDING DIFFERENT
VERSIONS OF LIPID TWO,
YOU CAN THEN ZERO IN.
AND IT IS THE LIPID
SUGAR PART.
THIS IS WHAT TAKES IT
BACK.
THE NATURE OF THE SUGAR
IS NOT IMPORTANT SO THAT
TOLD US THAT IT WILL
ALSO PROBABLY BUY AND
INDEED IT DOES, TO THE
IMPORTANT POLYMER.
IT HAS THE SAME
STRUCTURE, JUST A
DIFFERENT SUGAR.
SO THIS INVESTIGATION
TELLS US AN INTERESTING
THING.
IT INDICATES THAT NATURE
EVOLVED THE COMPOUND TO
BE FAIRLY FREE OF
RESISTANCE.
IT HITS TWO TARGETS.
NEITHER OF THESE TARGETS
IS MUTABLE.
THESE THINGS ARE NOT
CODED BY GENES, AT LEAST
NOT DIRECTLY.
THE TARGET ITSELF IS
EXPOSED ON THE SURFACE
OF THE CELL SO YOU
CANNOT PUMP IT OUT.
IT'S ALREADY OUTSIDE.
AND IT APPEARS THAT THE
MAIN DOING MA THAT WE'VE
BEEN OPERATING UNDER
WHICH IS BACTERIA WILL
DEVELOP RESISTANCE TO
EVERYTHING AND IN MANY
CASES RAPIDLY IS
PROBABLY INCORRECT.
THEY ARE PROBABLY
COMPOUNDS THAT EVOLVED
TO BE LARGELY FREE OF
RESISTANCE DEVELOPMENT.
SO GOING AFTER THOSE
COMPOUNDS I THINK MAKES
A LOT OF SENSE.
SO WITH THAT I WILL
THANK MY TEAM.
I WILL THANK MY
COLLABORATORS IN SUPPORT
WHICH HAS BEEN
SUPPORTING THE WORK OF
MY TEAM OVER THE YEARS,
AND I THANK YOU FOR
LISTENING.
[ APPLAUSE ]
>> IF THERE'S A
QUESTION, I THINK YOU
NEED TO GO TO THE
MICROPHONE.
>> YOU WERE SPEAKING
ABOUT BIO FILMS.
YOU DIDN'T SAY ANYTHING
ABOUT THE STRUCTURE OF
BIO FILM.
SUPPOSEDLY THEY HAVE AN
OUTER LAYER OF
PROTECTORS AND INNER
LAYER OF GUYS KIND OF
PROTECTED AND LOWER
LAYER OF SOMETHING ELSE.
CAN THE TYPE OF THING
YOU'RE TALKING ABOUT
ACTUALLY BEAT ALL OF THE
LAYERS OF A BIO FILM OR
PARTICULARS THAT ARE
LAID OUT FLAT.
THAT IS SIGNIFICANT
BECAUSE WHAT YOU'RE 3
TALKING ABOUT IS IT
MEDICAL DEVICES THAT ARE
GOING TO BE IN DWELLING
AND THEY DO DEVELOP ALL
OF THOSE DIFFERENT
LAYERS OF THINGS.
>> SURE.
OF COURSE THIS IS AN
IMPORTANT QUESTION AND
THERE ARE TWO ASPECTS TO
IT.
ONE IS THE ABILITY OF
THE COMPOUND TO
PENETRATE THROUGH.
AND THOUGH THERE'S THE
ABILITY TO KILL CELLS,
SO THE ABILITY OF
COMPOUNDS TO PENETRATE
INTO THE BIO FILM HAS
BEEN WELL DEMONSTRATED
WITH FEW EXCEPTIONS.
MOST COMPOUNDS PENETRATE
FAIRLY WELL.
THERE'S SOME PROBLEM,
THERE'S SOME RETARDED
PENETRATION.
THE MAIN PROBLEM IS NOT
PENETRATION INTO BUT THE
ABILITY TO KILL CELLS IN
THE BIO FILM WHICH ARE
DORMANT.
WHAT WE SHOWED
PREVIOUSLY IS THE MOST
DIFFICULT CELLS TO KILL
ARE NOT CELLS IN THE BIO
FILM BUT A SIMPLE
STATIONARY CULTURE.
SO ADEP KILLS CELLS IN
STATIONARY CULTURE AND
IN -- INVITRO.
>> THANK YOU.
>> THE FIRST PART OF
YOUR LECTURE, YOU SPOKE
ABOUT DIFFERENT KINDS OF
MECHANISMS BEHIND
PERSISTER FORMATION.
AND THEN THERE ARE
SPECIFIC MECHANISMS
BROUGHT ABOUT BY TOXINS,
SO COULD YOU ELABORATE
UNDER WHAT KIND OF
CIRCUMSTANCES, IN WHAT
SITUATIONS THESE
SPECIFIC MECHANISMS ARE
INVOLVED.
>> MY ELABORATION IS
LIMITED BY MY IGNORANCE
SO I WILL ONLY TALK
ABOUT SOME CLEAR
EXAMPLES THAT WE HAVE AT
THE MOMENT.
A GOOD EXAMPLE THAT WE
HAVE IS THE INDUCTION TO
B TOXIN.
DURING DNA DAMAGE, DNA
REPAIR.
THAT RESPONSE ACTIVATES
AND YOU HAVE ALSO AN
ACTIVATION OF THAT
EXPRESSION WITH THEM.
WHICH CONTROLS THE
ENTIRE SOS RESPONSE.
SO GETS ACTIVATED,
INSERTS ITSELF IN THE
MEMBRANE.
IT IS A VERY STRANGE
MONTHLY CULTURE THAT
DIMINISHES, DECREASES
ATP, AND THAT'S HOW YOU
GET PERSISTENCE UNDER
THOSE VERY SPECIFIC
CONDITIONS.
SO IN OTHER WORDS, UNDER
TYPES OF STRESS, YOU
WOULD IMPLICATE ALL
TOXINS BUT UNDER GENERAL
CONDITIONS THE
SPONTANEOUS --
>> MY FEELING IS THAT
PROBABLY UNDER
CONDITIONS WHERE THE
CULTURE IS NOT
NECESSARILY, STRESS IS
PRIMARILY GUIDED BY
ADEP LEVELS.
>> LET ME ASK TWO
QUESTIONS ABOUT THE
ENVIRONMENTAL
MICROBIOLOGY THAT COMES
OUT OF SOME OF THE
THINGS THAT YOU DO.
THAT YOU SEE BEING
BORROWED BY WHAT WAS
OTHERWISE
NON-CULTUREABLE ONES,
ARE THOSE GOING TO BE
SPECIFIC TO WHOSE IN THE
NEIGHBORHOOD IF YOU
TRIED AN UNCULTUREABLE
SOME PLACE ELSE?
>> THAT'S A GREAT
QUESTION AND WE EXAMINED
THAT, AND WHAT WE FOUND
IS THAT THERE'S EVERY
LOGICALLY POSSIBLE
SCENARIO.
SO WE FOUND SOME
BACTERIA THAT WILL ONLY
TAKE IT FROM A
PARTICULAR NEIGHBOR AND
THEN WE FOUND THOSE THAT
WE COULD INDUCE GROWTH
WITH THAT WE COULD BUY
COMMERCIALLY AND
EVERYTHING IN BETWEEN.
>> SO WE'LL EVENTUALLY
UNDERSTAND IT BUT NOT
YET AND PROBABLY THE
ANSWER TO THE OTHER
QUESTION SAID THE
BACTERIA THAT GAVE YOU
YOUR ANTIBIOTIC,
ANYTHING KNOWN ABOUT WHY
IT WOULD BE MAKING THIS
AND PRESUMABLY KILLING
OFF ALL ITS GROUND
POSITIVE NEIGHBORS?
>> THAT'S AN EXCELLENT
QUESTION.
IN ONE SIMPLE SCENARIO,
YOU WANT TO GET RID OF
YOUR NEIGHBORS.
THAT'S A COMMON
SENTIMENT, AT LEAST OF
WILD CREATURES.
SO PUT THERE'S ONE
PARTICULAR PROPERTY THAT
KIND OF TELLS US WHY
THAT COMPOUND, SO WHAT
WE FOUND ABOUT, IT HAS A
TERRIFIC ACTIVITY TO
Y CELLS, BETTER THAN ANY
OTHER CELL.
PROBABLY BECAUSE IT HITS
THESE TWO TARGETS.
AND SO I THINK THAT THIS
CREATURE IS A HUNTER.
I THINK IT HUNTS AND
EATS THEM.
>> CAN THERE BE DRAWN A
PARALLEL -- WHICH OCCUR
WHEN RECEPTORS WON'T
RESPOND --
>> WHY NOT.
[ APPLAUSE ]
