This still from a video that shows how lyzozyme consumes harmful bacteria highlights the “jaw” which clamps shut when the yellow and the green segments are drawn closer together. |
A
disease-fighting protein in our teardrops has been tethered to a tiny
transistor, enabling UC Irvine scientists to discover exactly how it
destroys dangerous bacteria. The research could prove critical to
long-term work aimed at diagnosing cancers and other illnesses in their
very early stages.
Ever
since Nobel laureate Alexander Fleming found that human tears contain
antiseptic proteins called lysozymes about a century ago, scientists
have tried to solve the mystery of how they could relentlessly wipe out
far larger bacteria. It turns out that lysozymes have jaws that latch on
and chomp through rows of cell walls like someone hungrily devouring an
ear of corn, according to findings that will be published Jan. 20 in
the journal Science.
“Those
jaws chew apart the walls of the bacteria that are trying to get into
your eyes and infect them,” said molecular biologist and chemistry
professor Gregory Weiss, who co-led the project with associate professor
of physics & astronomy Philip Collins.
The
researchers decoded the protein’s behavior by building one of the
world’s smallest transistors – 25 times smaller than similar circuitry
in laptop computers or smartphones. Individual lysozymes were glued to
the live wire, and its eating activities were monitored.
“Our
circuits are molecule-sized microphones,” Collins said. “It’s just like
a stethoscope listening to your heart, except we’re listening to a
single molecule of protein.”
It
took years for the UCI scientists to assemble the transistor and attach
single-molecule teardrop proteins. The scientists hope the same novel
technology can be used to detect cancerous molecules. It could take a
decade to figure out, but would be well worth it, said Weiss, who lost
his father to lung cancer.
“If
we can detect single molecules associated with cancer, then that means
we’d be able to detect it very, very early,” Weiss said. “That would be
very exciting, because we know that if we treat cancer early, it will be
much more successful, patients will be cured much faster, and costs
will be much less.”
The
project was sponsored by the National Cancer Institute and the National
Science Foundation. Co-authors of the Science paper are Yongki Choi,
Issa Moody, Patrick Sims, Steven Hunt, Brad Corso and Israel Perez.
