Thursday 29 July 2021

Coronavirus is affecting pregnancy and birth trends


One of the interesting social observations during the coronavirus era is the changes in trends for pregnancy and births. The era of the pandemic has apparently slowed down conception rates.


On the other hand the easing of lockdown may be heralding the start of a baby boom. Both of these trends relate to the U.S. economy, based on research conducted by the University of Michigan.


According to lead researcher Dr. Molly Stout: "Birth rates declined early on in the pandemic, but we expect a dramatic rebound soon.”


She is basing this on a review of electronic health records for a cohort of pregnancies. These analyses have enabled a model for pregnancy episodes to be developed, one that should stand up to other societal changes. The model offers a new perception on reproductive choices, population growth and fertility rates.


Interestingly, similar patterns were observed, albeit will less sophisticated models, during the 1918 H1N1 influenza pandemic, the Great Depression in 1929 and the recession of 2008. In other words, strong external factors are associated with changes in behaviors, especially in relation to conception.


There are a range of factors to explain the 2021 review, including stress and time pressures. Behind these lies  economic uncertainty, lack of childcare or no access to standard child support systems. There are related factors with the role of women at work.


For example, at the institution studied, pregnancy volumes decreased by about 14 percent (using the most restrictive coronavirus measures).


This new review will allow hospitals and governmental agencies to gain a better insight into population dynamics. Understanding this can help with hospital capacity planning as well as the running of health promotion schemes.


In addition, government agencies will be more accurately able to estimate the size of the economy and, from this, model working or aging populations.


Since the study was based on one medical institution (a single tertiary care academic center), then further research will be necessary assess how applicable the model is to the rest of the U.S. (and perhaps worldwide).


The research appears in  JAMA Network Open, titled “Use of Electronic Medical Records to Estimate Changes in Pregnancy and Birth Rates During the COVID-19 Pandemic.”


Posted by Dr. Tim Sandle, Pharmaceutical Microbiology Resources (

Wednesday 28 July 2021

Bioengineering discovery paves way for improved production of bio-based goods

                                                         Image by Public Domain,

Scientists have uncovered a way to control many genes in engineered yeast cells, opening the door to more efficient and sustainable production of bio-based products.


The study, published in Nucleic Acids Research by researchers from DSM's Rosalind Franklin Biotechnology Center in Delft, the Netherlands, and the University of Bristol, has shown how to unlock CRISPR's potential for regulating many genes simultaneously.


Baker's yeast, or Saccharomyces cerevisiae to give it it's full name, is considered as a workhorse for biotechnology. Not only has it been used for producing bread and beer for thousands of years, but today it can also be engineered to produce an array of other useful compounds that form the basis of pharmaceuticals, fuels, and food additives. However, achieving optimal production of these products is difficult, requiring the complex biochemical networks inside the cell to be rewired and extended through the introduction of new enzymes and the tuning of gene expression levels.


Klaudia Ciurkot, first author of the study and an EU-funded industrial PhD student based at DSM stated: "To overcome the challenges of optimising S. cerevisiae cells for bio-production, we explored the use of a less widely employed CRISPR technology based on the Cas12a protein. Unlike the Cas9 protein that is more commonly used, Cas12a can be rapidly programmed to interact with sequences that are responsible for controlling gene expression and easily targeted to many different sequences at the same time. This made it an ideal platform for carrying out the complex gene regulation often required for producing industrially relevant compounds."


She went on to add: "What was particularly exciting for me was that this study is the first to demonstrate Cas12a's ability to control gene expression in S. cerevisiae and through joint research across DSM and the University of Bristol, we were able to figure out the rules for how this system is best designed and used."



Thomas Gorochowski, a co-author on the work and Royal Society University Research Fellow based in the School of Biological Sciences at the University of Bristol further stated: "It is hugely exciting that Cas12a has been shown to work so well for gene regulation in the yeast S. cerevisiae, an organism that has huge industrial importance. In addition, the systematic approach we have taken to pull apart and analyse the many difficult aspects of the system, act as a firm foundation for future optimisation."


In addition to analysing how the Cas12a-based system is best engineered, the scientists went on to show its use in robustly controlling the production of β-carotene -- an industrially important compound used in production of food additives and nutraceuticals.




Klaudia Ciurkot, Thomas E Gorochowski, Johannes A Roubos, René Verwaal. Efficient multiplexed gene regulation in Saccharomyces cerevisiae using dCas12a. Nucleic Acids Research, 2021; DOI: 10.1093/nar/gkab529


Posted by Dr. Tim Sandle, Pharmaceutical Microbiology Resources (

Tuesday 27 July 2021

Unlocking the ‘gut microbiome’ – and its massive significance to our health

                                                             Image by Gabriele Berg, Daria Rybakova (doi:10.1186/s40168-020-00875-0)

“The gut microbiome is the most important scientific discovery for human healthcare in recent decades,” says James Kinross, a microbiome scientist and surgeon at Imperial College London. “We discovered it – or rediscovered it – in the age of genetic sequencing less than 15 years ago. The only organ which is bigger is the liver.” And, for all that the internet may be full of probiotic or wellness companies making big health claims about gut health, “We don’t really know how it works,” he says.

An interesting pop-sci aticle has been published in The Guardian.

Your gut microbiome weighs about 2kg and is bigger than the average human brain. It’s a bustling community of trillions of bacteria, archaea, fungi and viruses, containing at least 150 times more genes than the human genome. We are filled to the brim with microbes, which form microbiomes on our skin, in our mouths, lungs, eyes, and reproductive systems. These have co-evolved alongside us since the beginning of human history. But the gut’s is the largest and most significant for our short- and long-term health. It is massively complex and its residents vary enormously from person to person. According to a study in 2020 by the European Bioinformatics Institute, which pooled more than 200,000 gut genomes to create a genetic database of human gut microbes, 70% of the microbial populations it listed – 2,000 species – hadn’t yet been cultured in a lab and were previously unknown.

Access the article here:

The best book about the microbiome: 

Posted by Dr. Tim Sandle, Pharmaceutical Microbiology Resources (

Monday 26 July 2021

What are postbiotics?

Image: (c) Tim Sandle
The idea of deriving health benefits from live microorganisms is well known, but some non-living microorganisms, too, can have beneficial health effects. Yet even with an increasing number of scientific papers published on non-viable microbes for health, the category is not well defined and different terms are used in different contexts.

Now, a group of international experts has clarified this concept in a recently published scientific consensus definition in Nature Reviews Gastroenterology & Hepatology. The authors use an established term –postbiotics– and precisely define it as “a preparation of inanimate microorganisms and/or their components that confers a health benefit on the host“.

According to the definition, postbiotics may include either whole microbial cells or components of the cells, as long as they have somehow been deliberately inactivated.

Professor Seppo Salminen, lead author on the publication, says the group of experts — from across the disciplines of probiotics and postbiotics, adult and pediatric gastroenterology, pediatrics, metabolomics, regulatory affairs, microbiology, functional genomics, cellular physiology and immunology — wanted to clarify that postbiotics are more complex than the common idea of ‘heat-killed probiotics’.

Read more about this at Microbiome Times: International group of experts publish consensus definition of 'postbiotics' - Microbiome Times MagazinePosted by Dr. Tim Sandle, Pharmaceutical Microbiology Resources (

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 (

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