nanotechnology and antibiotic resistance
TRANSCRIPT
are made of.
That means this mechanism has the potential to be used to design more broad-spectrum antibiotics, which make up the first line of defence against bacterial infections.
Many bacteria are rapidly evolving ways to counter common antibiotics.
By using the body’s own defences as inspiration, re-searchers can engineer en-tirely new molecules that physically attack bacterial membranes.
Although we have a long
way to go before we see
this behind pharmacy coun-
ters, the design of Tilamin is
definitely another step for-
ward in our race against
antibiotic resistance.
Source :
http://www.studentnewspaper.org/a-
new-tool-in-the-fight-against-antibiotic-
resistance/
Scientists from the London Centre for Nanotechnology and the National Physics Laboratory have discovered a potential new way of kill-ing harmful bacteria: by peeling them.
Their innovative method can kill bacteria within minutes, making it an ex-citing discovery in the race to find new antibiotics.
However, the underlying principle is not anything new. The body has many built-in defences against microbial intruders, includ-ing tiny molecules called antimicrobial peptides (AMPs).
These peptides attach to bacterial surfaces and fold themselves up into struc-tures that can pierce through the protective lay-ers, forming pores.
The pores let the contents of a bacterial cell flow out, or let antibacterial mole-cules flow in. At high con-centrations of AMPs, this can kill the bacteria, but at low concentrations, it only makes small, temporary pores without much effect.
Inspired by the body’s own natural defences, the team of researchers designed a new peptide, called Tilamin, which is based on an ex-isting AMP. The surface of a bacterial cell is covered with
molecules that protect it from our immune system and help it keep its shape.
Its surface has an inner layer called a cytoplasmic mem-brane, and an outer one called a cell wall.
The (inner) cytoplasmic membrane is made of two layers of a molecule called a phospholipid, which has a hydrophilic (water-loving) head and a hydrophobic (water-repelling) tail.
Since both the inside of a bacterium and its outside environment are full of wa-ter, the two layers of phos-pholipids are arranged with the heads pointing out-wards and the tails inside.
AMPs usually form a pore straight through the mem-brane, but Tilamin attacks at an angle, forming a hole through one layer of phos-pholipids. This exposes the hydrophobic tails in the in-ner layer to water.
As more pores form, they
expand and merge together,
making the membrane
quickly disintegrate. The
membrane ruptures and the
bacterium can no longer
exist.
Tilamin seems to be non-specific, affecting different kinds of bacteria regardless of what their cell envelopes
A new tool in the fight against antibiotic resistance?
Nanotechnology and Antibiotic Resistance
Why is antimicro-
bial resistance a
global concern?
New resistance mecha-
nisms are emerging and
spreading globally, threat-
ening our ability to treat
common infectious dis-
eases, resulting in pro-
longed illness, disability,
and death.
Without effective antimi-
crobials for prevention
and treatment of infec-
tions, medical procedures
such as organ transplanta-
tion, cancer chemothera-
py, diabetes management
and major surgery (for
example, caesarean sec-
tions or hip replacements)
become very high risk.
Antibiotic Resistance is
growing concern amongst
medical and research fra-
ternities across the globe
Novocus Legal LLP 07– November—2016
ence at SEAS. Inspired by the carnivorous Nepenthes pitcher plant, which uses the porous surface of its leaves to immobilize a layer of liquid water, creating a slippery surface for captur-ing insects, Aizenberg previ-ously engineered industrial and medical surface coatings that are able to repel unwanted substances as diverse as ice, crude oil and biological materials.
Source : http://www.nanowerk.com/nanotechnology-news/newsid=44956.php
Implanted medical devices such as left ventricular-assist devices for patients with heart failure or other support systems for patients with respiratory, liver or other end organ disease save lives every day. Howev-er, bacteria that form infec-tious biofilms on those de-vices, called device-associated infections, not only often sabotage their success but also contribute to the rampant increase in antibiotic resistance cur-rently seen in hospitals. As reported in Biomaterials ("An immo-bilized liquid interface pre-vents device associated bac-terial infection in vivo"), a team led by Joanna Aizen-berg, Ph.D., and Elliot Chaikof, M.D., Ph.D., at the Wyss Institute for Biological-ly Inspired Engineering and the Harvard John A. Paulson School of Engineering and Applied Sciences at Harvard University (SEAS), as well as the Beth Israel Deaconess Medical Center (BIDMC), has created self-healing slippery surface coatings with medical-grade teflon materials and liquids that prevent biofilm formation on medical implants while preserving normal innate immune responses against pathogenic bacteria.The technology is based on the concept of 'slippery liquid-infused porous surfac-es' (SLIPS) developed by Aizenberg, who is a Wyss
Institute Core Faculty member, Professor of Chemistry and Chemical Biology and the Amy Smith Berylson Professor of Mate-rials Science at SEAS. In-spired by the carnivorous Nepenthes pitcher plant, which uses the porous sur-face of its leaves to immobi-lize a layer of liquid water, creating a slippery surface for capturing insects, Aizen-berg previously engineered industrial and medical sur-face coatings that are able to repel unwanted sub-stances as diverse as ice, crude oil and biological ma-terials.
The technology is based on the concept of 'slippery liq-uid-infused porous surfac-es' (SLIPS) developed by Aizenberg, who is a Wyss Institute Core Faculty mem-ber, Professor of Chemistry and Chemical Biology and the Amy Smith Berylson Professor of Materials Sci-
Creating Slippery Slope on surface of medical implants
Nanotechnology and Antibiotic Resistance
Antibiotic Resistance is
growing concern amongst
medical and research fra-
ternities across the globe
Novocus Legal LLP 07– November—2016
The SEM image on the left shows a commonly used teflon surface implanted into
mice that were infected with S. aureus. The unmodified device surface attracted the
infectious bacteria (green). Red blood cells (red), immune cells (blue), and extracel-
lular matrix material (yellow) are also shown to deposit on the surface. The SEM
image on the right (colored purple) is of the same teflon surface treated with SLIPS
within the infected mice. It shows no adhesion of cells or deposition of extracellular
matrix material. (Image: Wyss Institute at Harvard University)
they are needed, but also
intensify their impact at
the target site.
In a next step, the re-
searchers want to struc-
ture the nanocarriers in a
way that enables them to
take effect at a specific
time. The peptides would
therefore be protected
within the nanostructure
and then released when
needed and as the result
of an alteration in their
structure. At the "press of
a button", so to speak.
This is especially im-
portant in the medical
field, for example when
treating open wounds or
u s i n g c a t h e t e r s . Source:
http://www.nanowerk.com/
nanotechnology-news/
Several peptides have an
antibacterial effect - but
they are broken down in
the human body too
quickly to exert this effect.
Empa researchers have
now succeeded in encas-
ing peptides in a protec-
tive coat, which could
prolong their life in the
human body. This is an
important breakthrough
because peptides are con-
sidered to be a possible
solution in the fight
a g a i n s t a n t i b i o t i c -
resistant bacteria. They
occur in many organisms
and constitute natural
weapons against bacteria
in the body, being known
as antimicrobial peptides.
They offer a possible –
and now also urgently
needed – alternative to
conventional antibiotics,
but have not yet been suc-
cessfully used in a clinical
context. The reason for
this lies in their structure,
which results in peptides
being broken down rela-
tively quickly inside the
human body, before they
can have an anti-bacterial
impact.In Empa's Bioin-
terfaces Department in St.
Gallen, a team led by Stef-
an Salentinig has now
succeeded, in collabo-
ration with the Univer-
sity of Copenhagen, in
developing a kind of
shuttle system made of
liquid-crystalline nano-
materia ls ( so-ca l led
nanocarriers), which pro-
tect the peptides and thus
ensure they safely reach
the target site.
The researchers have also
documented an addition-
al characteristic of the
nanocarriers. Peptides are
already effective against
bacteria when working
"alone" - but in combina-
tion with the carrier struc-
ture they are even strong-
er. Thus the protective
casings formed by the
lipids not only ensure the
safe delivery of the pep-
tides to the area where
Peptides vs. superbugs
Nanotechnology and Antibiotic Resistance
Antibiotic Resistance is
growing concern amongst
medical and research fra-
ternities across the globe
Novocus Legal LLP 07– November—2016
The peptides are located within the protective casing
of the nanocarriers. The anti-microbial activity of the
peptide is deployed when the structure of the
nanocarrier is altered by external influences.
As a result, the medi-
cines become ineffective
and infections persist in
the body, increasing the
risk of spread to others.
AMR threatens the
effective prevention and treatment of an ever-increasing range of infec-tions caused by bacteria, parasites, viruses and fungi.
AMR is an increas-
ingly serious threat to global public health that requires action across all government sectors and society.
Without effective
antibiotics, the success of major surgery and
Antimicrobial re-
sistance (AMR) hap-
pens when microor-
ganisms (such as
bacteria, fungi, virus-
es, and parasites)
change when they
are exposed to anti-
microbial drugs (such
as antibiotics, antifun-
gals, antivirals, anti-
malarials, and anthel-
mintics). Microorgan-
isms that develop
antimicrobial re-
sistance are some-
times referred to as
“superbugs”.
cancer chemotherapy would be compromised.
The cost of health
care for patients with resistant infections is higher than care for pa-tients with non-resistant infections due to longer duration of illness, addi-tional tests and use of more expensive drugs. Globally, 480 000 people
develop multi-drug re-
sistant TB each year,
and drug resistance is
starting to complicate the
fight against HIV and
malaria, as well.
Novocus Legal LLP We all know that Intellectual Property acts as a conduit for infusion
and diffusion of technology horizontally across various technical
sectors and vertically within the same technical sector. Today, even
diametrically opposite technical domains find some use same tech-
nology. Also, with advent of inter-disciplinary fields like biotechnol-
ogy, nanotechnology, medical devices and the like, it has become
impossible to segregate technical applications of a single technology
for only one technical sector.
One has to remain updated about all technical sectors in order to
progress in this knowledge driven economic environment.
Through our newsletter series we hope to help readers stay updat-
ed with some latest developments in nanotechnology.
Antimicrobial Resistance— What is it?