Thursday, 22 July 2021

Power of silver as an antimicrobial

                                         Source: By Ivar Leidus - Own work, CC BY-SA 4.0,

Antimicrobials are used to kill or slow the growth of bacteria, viruses and other microorganisms. They are essential to preventing and treating infections, but they also pose a global threat to public health when microorganisms develop antimicrobial resistance. A lab studied the mechanisms behind bacterial resistance to silver nanoparticles to determine if their ubiquitous use is a solution to this challenge or if it is perhaps fueling the fire.


One of the main drivers of antimicrobial resistance is the misuse and overuse of antimicrobial agents, which includes silver nanoparticles, an advanced material with well-documented antimicrobial properties. It is increasingly used in commercial products that boast enhanced germ-killing performance -- it has been woven into textiles, coated onto toothbrushes, and even mixed into cosmetics as a preservative.


The Gilbertson Group at the University of Pittsburgh Swanson School of Engineering used laboratory strains of E.coli to better understand bacterial resistance to silver nanoparticles and attempt to get ahead of the potential misuse of this material. The team recently published their results in Nature Nanotechnology.


The group sequenced the genome of the E.coli that had been exposed to silver nanoparticles and found a mutation in a gene that corresponds to an efflux pump that pushes heavy metal ions out of the cell.



The group then studied two different types of E.coli: a hyper-motile strain that swims through its environment more quickly than normally motile bacteria and a non-motile strain that does not have physical means for moving around. They found that only the hyper-motile strain developed resistance.


In the end, bacteria will still find a way to evolve and evade antimicrobials. The hope is that an understanding of the mechanisms that lead to this evolution and a mindful use of new antimicrobials will lessen the impact of antimicrobial resistance.


Journal Reference:


Lisa M. Stabryla, Kathryn A. Johnston, Nathan A. Diemler, Vaughn S. Cooper, Jill E. Millstone, Sarah-Jane Haig, Leanne M. Gilbertson. Role of bacterial motility in differential resistance mechanisms of silver nanoparticles and silver ions. Nature Nanotechnology, 2021; DOI: 10.1038/s41565-021-00929-w


Posted by Dr. Tim Sandle, Pharmaceutical Microbiology Resources (

Wednesday, 21 July 2021

Fungi that live in the gut influence health and disease

                                         Source: By RimmaKhaz - Own work, CC BY 4.0,

Bacteria's role in gut health has received a lot of attention in recent years. But new research led by scientists at University of Utah Health shows that fungi -- another microorganism that lives within us -- may be equally important in health and disease.


Fungi thrive in the healthy gut, but they can also cause intestinal damage that may contribute to inflammatory bowel disease (IBD). Experiments with mice show that normally, the immune system keeps fungi in check, targeting the microbe when it switches into a state that can cause harm. When the system is off-balance, disease is more likely to occur.

These insights open new avenues for developing therapeutics to improve gut health. The study shows proof of concept that, one day, vaccines could be used to curb gastrointestinal disease by enhancing natural immune responses that encourage a healthy balance of fungi and other gut microbiota.


To dig deeper, her team searched for the trigger of the immune response. Working with patient samples and carrying out tests with mice, they determined that the yeast Candida albicans -- one of the main species of fungi that reside in the human gut -- elicited the strongest immune response. Further investigation showed that antibodies zeroed in on elongated fungal cell types called hyphae, specifically binding to proteins called adhesins that help microbes stick to surfaces and become invasive.


With this target in hand, the researchers could more definitively probe the fungi's role in gut health. They found that mice populated with the yeast in its normal, rounded state remained healthy. In contrast, mice populated with Candida in its invasive form caused intestinal damage that resembled IBD. The results show that normal antibody responses in the gut inhibit disease by recognizing the harmful, hyphal form of fungi.


IBD isn't the only health condition associated with fungi. Another is vaginal yeast infections. The researchers determined that a vaccine being investigated as a remedy for yeast infection triggered an immune reaction against adhesin proteins that is similar to the reaction in Crohn's patients. When inoculated with the vaccine, mice normally prone to an IBD-like condition were less likely to develop disease.



The researchers are now investigating whether vaccines could help mitigate IBD in people -- and whether the same approach can be applied more broadly to shape other microbial communities in the gut. "We aim to exploit interactions with commensal microbes and the host immune system to harness microbial products for therapies," Round says.


In addition to implications for disease, the findings also suggest fungi may be important in the healthy gut. Typically, the immune system's job is to clear infections by getting rid of invasive organisms. In this case, fungi benefit from their interaction with antibodies. The immune reaction prods fungi from their invasive state into their rounded, budding state, which improves their survival in the gut.


Journal Reference:


Kyla S. Ost, Teresa R. O’Meara, W. Zac Stephens, Tyson Chiaro, Haoyang Zhou, Jourdan Penman, Rickesha Bell, Jason R. Catanzaro, Deguang Song, Shakti Singh, Daniel H. Call, Elizabeth Hwang-Wong, Kimberly E. Hanson, John F. Valentine, Kenneth A. Christensen, Ryan M. O’Connell, Brendan Cormack, Ashraf S. Ibrahim, Noah W. Palm, Suzanne M. Noble, June L. Round. Adaptive immunity induces mutualism between commensal eukaryotes. Nature, 2021; DOI: 10.1038/s41586-021-03722-w


Posted by Dr. Tim Sandle, Pharmaceutical Microbiology Resources (

Tuesday, 20 July 2021

Briefing the COVID-19 Vaccine Developments


The novel coronavirus spread throughout the globe in 2020 like a forest fire. The need for an immediate response felt across the world. With countries beginning to prepare for lockdown and shutting down borders, the need for an anti-COVID vaccine was a huge challenge back then.

A guest post by Saket Panicker

It is almost 18 months since the chase began. In January 2021 vaccines were introduced in the open market and by then most countries have picked up the pace to provide vaccines to their citizens. Amid the success of vaccination drives, a few countries have eased restrictions and a handful of them have turned mask-free to resume the pre-pandemic life. Nonetheless, the virus mutation has already started to occur in the several parts of the world having a deadly impact on newly infected or vaccinated patients. Hence, initiatives, mission and collective efforts to curb the new COVID infection has already begun on the grass-root levels.

A market study from Grand View Research highlights that despite the speedy development of COVID-19 vaccine development tools and rollouts, the SARS COV-2 infection has just begun to plateau mainly in the developed countries. In terms of market estimation, the COVID-19 vaccine development tools market is expected to expand at 8.6% CAGR in the next few years.

Going forward, the WHO and CDC released vaccination toolkit and guidelines for effective administration of vaccine and tackling the challenges of distribution.

1) Guidelines of WHO:

The training modules, interactive exercises, and other content is available on the website of WHO reflecting much better on vaccination guidelines. In this context, the healthcare workers are undergoing essential training to ensure adequate safety while administering the COVID-19 vaccine. Additionally, the Access to COVID-19 Tools (ACT) Accelerator’s Country Readiness and Delivery Workstream has developed a national deployment and vaccination plan (NDVP). This course is intended to empower national and sub-national focal points.


2) Guidelines of ACIP:

The Centre for Disease Control and Prevention (CDC) released vaccine recommendations and guidelines of the ACIP. The Advisory Committee on Immunization Practices (ACIP) emphasizes more on offering healthcare personnel (HCP) and residents of long term care facilities (LTCF). It has prioritized vaccines for HCP who have been working long with COVID patients on direct or indirect basis.


Importance of COVID-19 vaccines:

l  COVID-19 vaccines have been formulated using all the clinical trials. The vaccines have also undergone extensive testing and monitoring to conclude safety and potency of the vaccine

l  The anti-COVID vaccines have gained tremendous importance in terms of human safety. Vaccination drives are conducted in full swing in most countries to ensure population sustainability in the years to come

l  These vaccines are effective to encourage herd immunity based on rapid vaccination. Besides, these are effective against severe effects of COVID-19 and provides an immunity boost in people who have reCOVered from COVID-19

l  The infection from COVID-19 is still a serious threat among the unvaccinated population leading them in prolonged hospitalization and making them vulnerable for long-term COVID effects

l  Last but not the least, vaccine studies reveal that an individual can resume many activities from the pre-pandemic life provided that the social distancing norms and COVID appropriate behaviour is followed. It also include adhering to guidelines from local authorities and governing bodies

Key Takeaway:

The WHO, CDC and other medical authorities are encouraging vaccine production by empowering the producers with the clinical approvals. The toolkit clearly demonstrates the deadly nature of the virus and vaccine viability.

According to Grand View Research, vaccine manufacturers such as Thermo Fisher Scientific, Sartorius AG, Bio-Rad Laboratories and other life science industries are looking forward to focus on long-term reCOVery for SARS COV-2 infection. Whereas, companies like BioNtech, Pfizer, Moderna and Johnson & Johnson have extended their help overseas for vaccines. Therefore, the COVID-19 vaccine development tools industry is likely to witness some of the major collaborations and acquisitions in the very near future.

One needs to get fully vaccinated at the prescribed intervals. On the contrary, a lot of factors are obstructing the speed of vaccination drives. Unequal distribution, low COVerage and vaccine hesitancy are some of the known factors disrupting the vaccination drive around the world. Conclusively, it is an individual responsibility to get vaccinated as many experts have underlined the importance of getting a vaccine to reduce the feared dangers with the mutant variants.

Author’s  Bio:

Saket Panicker

Team Lead at Grand View Research, Inc.

Saket is a full-time business writer for Grand View Research which is an India & U.S. based market research and consulting firm. His ability to connect with the readers brings simplicity and clarity on the subject. His core expertise on subjects related to healthcare, information technology, consumer goods, and chemicals prove insightful for the readers. 

Posted by Dr. Tim Sandle, Pharmaceutical Microbiology Resources (

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