Quorum Sensing with
Prof. Bonnie Bassler
and
Prof. Peter Greenberg
人
類在1928年發現了盤尼西林，開啟了抗生素時
代，自此奮力與疾病作戰，探索病原體的致病機制。隨著抗
藥性的出現，我們面臨壓力要破解關於病原體的種種謎團，
以及開發新藥以應付不斷演變的細菌。
邦妮
•
巴斯勒教授
所研發的「抗群體感應療法」，正好有助解決這個長期存在
的問題，為此獲授予邵逸夫獎。
「群體感應」是指細胞或微生物之間的溝通。細胞會製
造一些稱為「信號」或「自體誘導物」的化學物，作用與荷
爾蒙類似，可被其它微生物探測，傳送不同信息如在周圍環
境中微生物的數量。以會發光的鯢弧菌為例，它們只在身邊
有足夠的同伴時才會發光，缺乏同伴時就會節省能量。過
去數十億年來，細菌都是這樣溝通，並為整體物種的利益而
集體行動。巴斯勒教授的團隊研發了阻斷信號受體的分子，
Battling
diseases and understanding
the mechanisms of harmful pathogens have
been an upward struggle since the discovery of
penicillin in 1928, marking the beginning of the
era of antibiotics. With the contention of drug
resistance, however, the pressure is back on to
break the enigma of pathogens and develop
new drugs to tackle ever-evolving bacteria.
Prof.
Bonnie Bassler
’s Shaw Prize winning research in
anti-quorum-sensing therapy is one such weapon
to tackle this ongoing problem.
Quo r om s en s i ng r e fe r s to t he fo r m o f
communication between cells or microorganisms.
Cells produce hormone-like chemicals known as
“signals” or “autoinducers” that can be picked up
by other microorganisms, containing information
such as the number of other microbes in their
immediate surroundings. For example,
Vibrio
fischerici
is known for its bioluminescence and only
glows when it detects enough of its compeers in
its proximity to increase virulence, and conserves
energy in the absence of its own kind. This is how
bacteria have communicated for billions of years,
and act collectively for the betterment of its
species. Prof. Bassler and her team have managed
to develop molecules that dis rupt quorum-
sensing by blocking signal receptors. In failing to
recognise the presence of compeers, bacteria
pathogenicity is reduced.
Antibiotics act to di sable
microbes by inhibiting
their metabolisms
or destroying their
cell structures.
Long term
or abusive
u s e o f
antibiotics,
however, could lead to bacterial drug resistance,
particularly when the dosage is inadequate to
eliminate bacteria. Each new antibiotic takes
many years to research and develop into fruition,
making this a very difficult problem to tackle when
bacteria can develop drug resistance in a much
shorter time. Anti-quorum sensing equips us with
an entirely new method of battling diseases.
“Since an anti-quorum-sensing strategy
would alter bacterial behaviour, rather
than outright kill bacteria or slow their
growth, resistance would come about
more slowly than with traditional anti-
bacterials,”
Prof. Bassler pointed out.
In other words, when bacteria are not being
killed, evolutionar y pressure to sur vive is less
per tinent and buys the immune system extra
time to eliminate them. This innovative strategy is
without a doubt “a promising route to controlling
bacteria”.
