THAT, UNTIL RECENTLY, HAS NEVER BEEN SEEN BY HUMANS.

THESE RESEARCHERS ARE BRAVING PRECARIOUS AND CLAUSTROPHOBIC PASSAGEWAYS THIRTY FEET DEEP

IN THE EARTH — ALL IN A RACE TO DISCOVER WHAT COULD SAVE MILLIONS OF OUR LIVES.

ANN: You plunge yourself down into totally pitch darkness.

You can't even see your own hand.

I have to confess here that I have to turn my brain off,

so that I wouldn't imagine the worst that could happen in the cave.

I don't like caves, yeah... but I'm doing it for work.

These soda straws are speleothems, which basically means secondary mineral deposits.

We thought the formation was caused by physical and chemical interaction, but actually now

everywhere we look we see lots of bacteria living in this soda straw formation.

Each year, this grows only maybe 1 mm or smaller, so these formations could be

500 years old or longer.

A thousand years, this length.

Or more.

DR. NAOWARAT CHEEPTHAM, OR "ANN," IS COMBING THE IRON CURTAIN CAVE - AND OTHER CAVES -

FOR A NEW ANTIBIOTIC THAT CAN FIGHT THE QUICKLY SWELLING CRISIS

OF DRUG-RESISTANT SUPERBUGS.

ANN: If we go into a hospital these days, some of us might not come back.

I mean, I'm sorry but it's that dire, the situation right now.

We don't have enough antibiotics in our toolbox to actually fight against these infections.

WHAT WOULD A WORLD WITHOUT EFFECTIVE ANTIBIOTICS REALLY LOOK LIKE?

MORE LIKE THE DARK AGES.

SURGERIES ARE FAR MORE DANGEROUS.

CHILDBIRTH MORTALITY RATES SOAR.

TRAVEL BETWEEN COUNTRIES IS TOO RISKY, DUE TO OUTBREAKS.

BY 2050, THERE WILL BE TEN MILLION DEATHS A YEAR FROM DRUG-RESISTANT INFECTIONS...

MORE THAN THE ANNUAL NUMBER OF DEATHS FROM CANCER.

AND IT'S HAPPENING BECAUSE OUR ONLY ANTIBIOTICS, MOST OF WHICH

ARE OVER THIRTY YEARS OLD, CAN NO LONGER OUTSMART INFECTIOUS BACTERIA.

ANN: Bacteria are way smarter than us.

They adapt so quickly, and they are very resourceful as well.

Every life on earth, we want to survive.

Bacteria are just like us in that sense. They want to survive.

There will be one or two of them that are strong enough, and stronger than the drug

that we put in, that they can still survive, and then they will multiply.

Basically this is the the law of nature, that you have these antibiotic-resistant

groups of bacteria.

WHICH MEANS, EVEN IF ANN FINDS THE NEXT ANTIBIOTIC, ONE DAY,

BACTERIA WILL BECOME RESISTANT TO IT AGAIN.

BUT A NEW DRUG WOULD STILL BUY US TIME.

AND WITH OVER ONE TRILLION MICROBIAL SPECIES YET TO BE DISCOVERED,

ANN HAS TO START SOMEWHERE.

THE IRON CURTAIN CAVE ECOSYSTEM IS SO RICH WITH LIFE BRAND NEW TO SCIENCE

THAT THERE'S HOPE AT LEAST ONE SPECIES COULD HOLD THE FORMULA FOR A NEW DRUG.

ANN: The bacteria themselves are not truly antibiotics in that sense,

but it is their metabolites that they produce.

We use these molecules as our antibiotics and

basically the source of antibiotics and new drugs.

SECONDARY METABOLITES ARE BIOLOGICALLY ACTIVE SMALL MOLECULES THAT HAVE OFTEN

BEEN THE SOURCE OF MEDICINE IN THE PAST.

THEY ARE A BY-PRODUCT OF BACTERIA, NOT REQUIRED FOR SURVIVAL,

BUT FOR A COMPETITIVE ADVANTAGE AGAINST OTHER SPECIES.

HOWEVER, ANN AND OTHER RESEARCHERS THINK SECONDARY METABOLITES

COULD SERVE AN ADDITIONAL PURPOSE.

ANN: I think there is more evidence now that these types of metabolites that they produce

during their life cycle are used as a tool for communication within themselves,

within their own species, and also between other species as well.

Instead of killing each other off and using a competitive mode of living, wouldn't it

be more beneficial for their own community to actually communicate and work together,

to achieve the same goal of surviving?

With that said, we want to look deeper into whether they produce certain kinds of

metabolites what we could use for our benefit.

UNDERSTANDING ANY DETAILS LIKE THESE ABOUT BACTERIA'S BEHAVIOR OR THEIR ENVIRONMENT

COULD HELP IN ANN'S QUEST FOR A NEW ANTIBIOTIC.

AND AS IF THAT TASK WASN'T MONUMENTAL ENOUGH,

CAVE ENVIRONMENTS ARE FACING A NEW THREAT,

THAT, IF IT CONTINUES, COULD THROW ANN'S MEDICINAL RESEARCH OFF-COURSE.

ANN: I never planned to study with bats, but I can see that it is important, and as a microbiologist,

I feel responsible.

ANN HAS ADDED THE PLIGHT OF BATS TO HER RESEARCH, BECAUSE OF AN EPIDEMIC

CALLED WHITE NOSE SYNDROME.

THIS FUNGAL INFECTION HAS ALREADY KILLED SIX MILLION BATS IN NORTH AMERICA.

WITHOUT BATS, CAVE ECOSYSTEMS WILL CHANGE.

AND THAT COULD BE A PROBLEM FOR FINDING THE NEXT ANTIBIOTIC.

AND EVEN THOUGH ANN IS A MICROBIOLOGIST, SHE SEES THE ROLE OF BATS IN THE BIGGER PICTURE.

ANN: Can you imagine, it's just like you look at this thousand piece puzzle, and bats

may be contributing to just one small piece of that puzzle.

But if this piece of puzzle actually gets lost, the whole puzzle will never be complete

in the same way.

We need to be careful with our heads, and also our hands... we have to make sure

we are not touching or breaking the mineral deposits that the cave has.

ANN IS LOOKING FOR SODA STRAW SPELEOTHEMS MADE OF CALCIUM CARBONATE OR CALCIUM SULFATE.

IT IS BELIEVED THAT THE IMPACT OF CALCIUM'S POSITIVELY CHARGED IONS BETWEEN BACTERIA DNA

STRANDS COULD BE THE KEY TO KILLING BACTERIA.

ANN: We would like to take soda straw, popcorn, and then some samples,

especially from the octopus room.

And we would like to set up an experiment there.

ANN'S RESEARCH IN THE IRON CURTAIN CAVE HAS HAD PROMISING RESULTS SO FAR,

THOUGH IT IS A SLUGGISH PROCESS.

BACTERIA CAN TAKE WEEKS TO GROW, AND ONLY THEN CAN ANN DETERMINE IF IT SHOWS PROMISE

AGAINST DRUG-RESISTANT SUPERBUGS.

ANN: Initially we found hundreds of bacteria.

We tried to isolate bacteria that live in the Iron Curtain Cave in the lab, and we found

fourteen of them, initially, that show activity against multidrug-resistant bacteria,

all those bad bacteria.

AT THAT POINT, THE SAMPLES LEAVE ANN'S LAB FOR GENOME SEQUENCING.

ANN: Now we actually singled out for the two of them, so we have the two hopefully superheros

right now.

OUT OF THE HUNDREDS OF SAMPLES SHE COLLECTED, ONLY TWO HAVE THE POTENTIAL TO BE WHAT ANN

CALLS “SUPERHERO BACTERIA.”

BUT JUST BECAUSE THEY WORK IN A PETRI DISH DOESN'T MEAN THEY WILL WORK IN HUMANS.

IT WILL TAKE BILLIONS OF DOLLARS AND MANY YEARS TO MOVE FORWARD WITH ANY POTENTIAL DRUG,

AND THERE'S VERY LITTLE PROFIT TO BE HAD.

THAT'S WHY THERE'S BEEN SLOW, IF ANY, PROGRESS IN THE LAST FEW YEARS.

ANN: I do believe that we have solutions, but all of us have to work together, not just

scientists, not just politicians, not just the pharmaceutical companies, not just the

policymakers...

every one of us needs to understand the implications of overuse and misuse of antibiotics in our

society, and how we can reduce that.

ANN DOESN'T LET THE DAUNTING COMPLICATIONS WAIVER HER.

INSTEAD, HER SEARCH CONTINUES.

ANN: This cave gets its name because of this beautiful backdrop here; you can see that

it takes numbers of years, possibly millions of years, to form...

I can imagine how many species of bacteria and microorganisms that live in that structure,

that formation.

And maybe... maybe one of them could actually be our superhero

that could produce new antibiotics

for us one day.

[THIS EPISODE WAS PRESENTED BY THE U.S. AIR FORCE.

LEARN MORE AT AIR FORCE.COM.]

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