Antimicrobial resistance (AMR) threatens the effective prevention and treatment of an ever-increasing range of infections. It’s a leading mortality factor worldwide, but the newly discovered antibiotic, clovibactin, may offer a pivotal solution. It effectively kills drug-resistant bacterial pathogens without detectable resistance—even multidrug-resistant “superbugs.”
Global pandemics, such as COVID-19, have taught us to abhor viruses. The emergence of new, highly infectious viruses is—rightfully so—a cause for concern. However, despite the average human body harboring 380 trillion viruses, most of them simply coexist with us and are harmless. When it comes to an ancient lineage of viruses within the realm Duplodnaviria, researchers are even using them as weapons in the battle against infectious diseases.
In 1915, Frederick William Twort, an English bacteriologist at the University of London, reported the discovery of an unusual “ultramicroscopic virus” (1). Twort was culturing vaccinia virus as part of an experiment to determine if he could prepare smallpox vaccines in vitro. These vaccines, made in calves, were typically contaminated with Staphylococcus bacteria. When Twort plated the vaccines, he found small, clear areas on the agar plates where the bacteria would not grow, and these clear areas were the source of his ultramicroscopic virus. Two years later, a French-Canadian microbiologist, Félix d’Hérelle, independently discovered a similar phenomenon when culturing Shigella bacteria from fecal samples of patients with bacillary dysentery. He called the new virus “un bactériophage obligatoire” (2). Shortly after his discovery, he found that bacteriophages (phages) could be used as powerful agents to treat a variety of bacterial infections, and the field of phage therapy was born (3).
When someone is admitted to a hospital for an illness, the hope is that medical care and treatment will help them them feel better. However, nosocomial infections—infections acquired in a health-care setting—are becoming more prevalent and are associated with an increased mortality rate worldwide. This is largely due to the misuse of antibiotics, allowing some bacteria to become resistant. Furthermore, when an antibiotic wipes out the “good” bacteria that comprise the human microbiome, it leaves a patient vulnerable to opportunistic infections that take advantage of disruptions to the gut microbiota.
One such bacteria, Clostridium difficile, is of growing concern world-wide since it is resistant to many different antibiotics. When a patient is treated with an antibiotic, C. difficile can thrive in the intestinal tract without other bacteria populating the gut. C. difficile infection is the leading cause of antibiotic-associated diarrhea. While symptoms can be mild, aggressive infection can lead to pseudomembranous colitis—a severe inflammation of the colon which can be life-threatening.
C. difficile causes disease by releasing two large toxins, TcdA and TcdB. Understanding the role these toxins play in colonic disease is important for treatment strategies. However, most published research data only report the effects of the toxins independently. A 2016 study demonstrated a method of comparing the toxins side-by-side using the same time points and cell assays to investigate the role each toxin plays in the cell death that leads to disease of the colon. Continue reading “A Tale of Two Toxins: the mechanisms of cell death in Clostridium difficile infections”
It is estimated that all the bacterial species so far described represent only a tiny fraction of the total. The rest remain unknown to science because they are “unculturable” in standard (or known) laboratory media. Given that many antibiotics were first isolated from environmental bacteria, it seems likely that these as yet unknown organisms could also be a rich source of potential new drug candidates. The desperate need for new strategies to combat multi-drug resistant infections gives impetus to studies investigating how we can culture some of these “unculturable” bacteria and uncover their potential as a source of much-needed new treatments. Continue reading “Culturing the Unculturable”
Structure of the antibiotic meropenemLast month brought some hopeful news on the subject of antibiotic resistance. A paper published in Nature on June 26 described the isolation of a fungal compound that restored the antibiotic sensitivity of carbapenem-resistant enterobacteria. An editorial accompanying the paper took encouragement from the article–considering it a sign that the well of potential sources of new antimicrobial agents, and agents that inhibit resistance mechanisms, is not yet dry:
But the reservoir of natural products with the potential to act as antibacterial drugs has not yet been exhausted. In contrast to general thinking by drug companies, screening for such products may well still have a bright future” Nature News and Views: “Antibiotic resistance: To the rescue of old drugs” Meziane-Cherif & Courvalin, Nature 510, 477–478.
The emergence of bacteria that are resistant to antibiotics has been an object lesson in the relentlessness of natural selection; the moment a new antibiotic is developed and introduced, the countdown to the emergence of resistance begins. The race to keep the one step ahead of emerging resistance mechanisms has been going on since antibiotics were first introduced.
The history of the development of penicillin and related antibiotics is both an illustration of the ingenuity of scientists and of the never-ending nature of this battle with emerging resistance. The Nature paper is the latest installment in that story. Continue reading “Hope for Treatment of Carbapenem-Resistant Bacteria”
This month saw the publication of a UK Department of Health report on the growing problem of antimicrobial resistance, which included the shocking recommendation that antimicrobial resistance be added to the UK government list of threats to national security alongside terrorism and pandemic flu. In this report, Professor Dame Sally Davies, Chief Medical Officer for the UK, focused on the increasing problem of multidrug resistant organisms–raising the profile of an important issue that many scientists and health-care professionals have warned us about before. A March 12 Nature editorial welcomed the recommendations as a sign that policy makers in the UK are taking the threat of antimicrobial resistance seriously and are prepared to take more steps to address the problem of multidrug-resistant organisms. Continue reading “Antibiotics and Honey–An Old Solution for a New Problem”
As a scientist and a jewelry artist, there are not that many occasions when my two passions overlap. As a geneticist, I find the evolution and spread of antibiotic resistant microbes to be fascinating in a “this is really cool and utterly terrifying” sort of way. As a jewelry artist, I love experimenting with new and different metals. Some of my current favorites are stainless steel, copper and bronze, which is an alloy of copper and tin. So you might be able to imagine my excitement when I came across an article in mBio discussing the public health implications of horizontal gene transfer (HGT) of antibiotic resistance genes on clinical and public touch surfaces made from copper alloys compared to those made of stainless steel (1).
Stainless steel: The unexpected, gene-transferring truth
Stainless steel is often used in clinical and public settings as work surfaces as well as other surfaces that are touched and cleaned often. Stainless steel is used in these applications for many of the same reasons I like it for jewelry: it is strong, resilient, relatively inexpensive, stain- and corrosion-resistant and will weather regular cleaning/exposure to moisture well. There is something about a gleaming stainless steel work surface that looks, well, sterile. But is it? Continue reading “Copper Containing Surfaces and Their Potential for Reducing the Spread of Infection and Antibiotic Resistant Gene Transfer”
Some of the first available doses of penicillin were used to treat allied soldiers wounded on D-Day. It was the end of one war, but just the beginning of another–one that has gone on for a long time. The story of the development of antibiotics, and the emergence of resistant bacteria, followed by the renewed search for new antibiotics, seems neverending. As soon as a new antibiotic is discovered, it seems only a matter of time before a resistance mechanism emerges, and remaining one step ahead of the bugs can seem like a relentless challenge. Continue reading “The Search for New Antibiotics: Looking for Achilles’ Heel (Again)”
XWe use cookies and similar technologies to make our website work, run analytics, improve our website, and show you personalized content and advertising. Some of these cookies are essential for our website to work. For others, we won’t set them unless you accept them. To learn more about our approach to Privacy we invite you to Read More
By clicking “Accept All”, you consent to the use of ALL the cookies. However you may visit Cookie Settings to provide a controlled consent.
We use cookies and similar technologies to make our website work, run analytics, improve our website, and show you personalized content and advertising. Some of these cookies are essential for our website to work. For others, we won’t set them unless you accept them. To find out more about cookies and how to manage cookies, read our Cookie Policy.
If you are located in the EEA, the United Kingdom, or Switzerland, you can change your settings at any time by clicking Manage Cookie Consent in the footer of our website.
Necessary cookies are absolutely essential for the website to function properly. These cookies ensure basic functionalities and security features of the website, anonymously.
Cookie
Duration
Description
cookielawinfo-checbox-analytics
11 months
This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Analytics".
cookielawinfo-checbox-functional
11 months
The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional".
cookielawinfo-checbox-others
11 months
This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other.
cookielawinfo-checkbox-advertisement
1 year
The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Advertisement".
cookielawinfo-checkbox-necessary
11 months
This cookie is set by GDPR Cookie Consent plugin. The cookies is used to store the user consent for the cookies in the category "Necessary".
cookielawinfo-checkbox-performance
11 months
This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Performance".
gdpr_status
6 months 2 days
This cookie is set by the provider Media.net. This cookie is used to check the status whether the user has accepted the cookie consent box. It also helps in not showing the cookie consent box upon re-entry to the website.
lang
This cookie is used to store the language preferences of a user to serve up content in that stored language the next time user visit the website.
viewed_cookie_policy
11 months
The cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. It does not store any personal data.
Analytical cookies are used to understand how visitors interact with the website. These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc.
Cookie
Duration
Description
SC_ANALYTICS_GLOBAL_COOKIE
10 years
This cookie is associated with Sitecore content and personalization. This cookie is used to identify the repeat visit from a single user. Sitecore will send a persistent session cookie to the web client.
vuid
2 years
This domain of this cookie is owned by Vimeo. This cookie is used by vimeo to collect tracking information. It sets a unique ID to embed videos to the website.
WMF-Last-Access
1 month 18 hours 24 minutes
This cookie is used to calculate unique devices accessing the website.
_ga
2 years
This cookie is installed by Google Analytics. The cookie is used to calculate visitor, session, campaign data and keep track of site usage for the site's analytics report. The cookies store information anonymously and assign a randomly generated number to identify unique visitors.
_gid
1 day
This cookie is installed by Google Analytics. The cookie is used to store information of how visitors use a website and helps in creating an analytics report of how the website is doing. The data collected including the number visitors, the source where they have come from, and the pages visted in an anonymous form.
Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. These cookies track visitors across websites and collect information to provide customized ads.
Cookie
Duration
Description
IDE
1 year 24 days
Used by Google DoubleClick and stores information about how the user uses the website and any other advertisement before visiting the website. This is used to present users with ads that are relevant to them according to the user profile.
test_cookie
15 minutes
This cookie is set by doubleclick.net. The purpose of the cookie is to determine if the user's browser supports cookies.
VISITOR_INFO1_LIVE
5 months 27 days
This cookie is set by Youtube. Used to track the information of the embedded YouTube videos on a website.
Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors.
Cookie
Duration
Description
YSC
session
This cookies is set by Youtube and is used to track the views of embedded videos.
_gat_UA-62336821-1
1 minute
This is a pattern type cookie set by Google Analytics, where the pattern element on the name contains the unique identity number of the account or website it relates to. It appears to be a variation of the _gat cookie which is used to limit the amount of data recorded by Google on high traffic volume websites.