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Posts Tagged ‘Microbiology International’

Rest Assured That Your Anaerobic Workstation is at Zero Oxygen

The following was written by Microbiology International, Don Whitley Scientific’s supplier of the Anaerobic Workstation in the US

Don Whitley Scientific have turned the maintenance and monitoring of stringent anaerobes in their anaerobic workstations into an art. The unique combination of anaerobic conditions monitoring (ACM) and catalyst monitoring available on the  A35, A45, A55, A85 and A95 workstations guarantees that strict anaerobes really will be well within their comfort zone. Microbiology International is the North American distributor for these anaerobic workstations.

The ACM comprises of an oxygen sensor placed inside the workstation and software to process real-time data on oxygen levels in the chamber. Based on knowledge of bacterial oxygen tolerance, results are shown on the touchscreen interface as a colour-coded indicator of O2 concentration. Green, yellow, or red status bars clearly indicate to the user whether oxygen levels are acceptable and provide information on the correct functioning of the workstation. This fully automated system replaces resazurin strips, which can dry out and are subject to interpretation based on the pink-to-white colour change.

The palladium catalyst used to remove traces of oxygen in the Don Whitley Scientific anaerobic workstations is protected through the addition of Anotox, which removes volatile organic compounds and hydrogen sulfide from the chamber atmosphere. Proper functioning of this vital system is monitored by the patented Catalyst Monitoring System, which tests the function of the catalyst overnight, and also confirms that the necessary hydrogen is present.

Together, the anaerobic conditions and catalyst monitoring systems provide unambiguous proof that anaerobiosis is being maintained in the workstations. The art of “zero oxygen” is critically important to cultivating anaerobic microorganisms that, due to their fastidious nature, are often classified as “unculturable“. Taking advantage of the closed workstation format to establish a strictly controlled anaerobic atmosphere, researchers are using Whitley Workstations to examine diverse topics such as the degradation of complex glycans by human gut microbiota;  the rise in C. difficile infections through lawn contamination; and the anaerobic etiology of brain abscesses.

The A35 Anaerobic Workstation will be on the Don Whitley Scientific stand at this years IBMS Congress in Birmingham



Duck, duck, goose – diagnosis of avian botulism redefined

This article was provided by Microbiology International, Don Whitley Scientific’s US distributor of Anaerobic Workstations.

Large outbreaks of avian botulism with losses of over 50,000 wild birds occur regularly in Canada and the United States, and poultry farms worldwide also experience serious losses due to botulism neurotoxins. Clostridium botulinum is an obligate anaerobe that produces spores that persist for many years, and the botulinum toxin is one of the most potent toxins known to man.

Workstation users Le Marechal et al. at ANSES in France have previously developed a reliable, rapid and less expensive alternative to the mouse bioassay for confirmation of botulism, using liver from birds exhibiting symptoms as matrices for real-time PCR.  In their new paper “Development and Validation of a New Reliable Method for the Diagnosis of Avian Botulism”, Le Marechal et al. describe their investigation into optimised consensus conditions for the detection of type III avian botulism strains in liver.

The group at ANSES examined a number of parameters in developing their assay, including the options for pooling samples at different time points; times and temperatures of storage; homogenisation methods; and methods for producing anaerobic culture conditions. Both naturally contaminated and spiked liver samples were incubated in anaerobic jars, using either Gas-Paks or an anaerobic gas mix (10% CO2, 10% H2 and 80% N2), or in the Don Whitley Scientific A35 anaerobic workstation. Results were unambiguous: detection of low levels of some spores in anaerobic jars was only ~30% (gas mix) and ~65% (Gas-Pak) of the detection achieved in the A35 anaerobic chamber. The authors conclude that “Anaerobic chambers should therefore be preferred to detect low levels of type C spores.”

The A35, distributed in the US by Microbiology International, achieves reliably anaerobic culture conditions throughout the full internal volume of the chamber; the optional “anaerobic conditions monitoring system” senses and displays real-time oxygen levels for added security. Features such as automated humidity control, glove-less access ports, airlock and single-plate entry into the chamber, password protected user interaction and a removable front make the A35 the most user-friendly and reliable anaerobic workstation available to microbiology labs.

It’s no wonder Le Marechal et al. conclude, “The use of an anaerobic chamber was also better than the use of an anaerobic container, regardless of the anaerobic atmosphere. Therefore, insofar as possible, the use of an anaerobic chamber for the detection of Cbotulinum group III is recommended, especially for the detection of a low level of spores”.




Diagnosis scheme for avian botulism by detection of C. botulinumin livers using real-time PCR. Parameters optimized in this study are shown in bold. From “Development and Validation of a New Reliable Method for the Diagnosis of Avian Botulism”,










Microbiology International at ASM Microbe 2017

Don Whitley Scientific’s US distributor, Microbiology International, will be exhibiting at the upcoming American Society for Microbiology annual conference. The event, known as ASM Microbe, will be held in New Orleans from June 1st to June 5th. Microbiology International will be showcasing Don Whitley Scientific products at Booth 2837.

The ASM continues to be the international leader in advancing microbial sciences across the globe, boasting more than 50,000 members. The annual ASM Microbe conference gives delegates and exhibitors the chance to experience everything that is happening in microbiology and connect with bright minds across the broad scope of the industry. The five day programme includes keynote speakers, poster sessions, workshops and also an optional city tour of New Orleans.

The Microbiology International stand will feature the Whitley A55 Anaerobic Workstation. Representatives will be available to explain why this is the best option when it comes to a range of microbiology applications. Two unique features of these workstations are the Instant Access Port System and Anaerobic Conditions Monitoring. The first ensures the workstation is easy and comfortable to work in whilst ACM ensures anaerobic conditions are monitored, providing consistently reliable results.

If you are at this event make sure you visit Booth 2837 to discuss how our product range could help you in your work.

Cultivating the “Unculturables”

The oral bacteriome comprises about 700 species, most of them anaerobic and participating in symbiotic relationships with their human host and each other which are essential for overall health, not just of the mouth but also of the heart, the brain, and other organ systems. Up to one third of these bacteria have been characterised solely by culture-independent molecular methods such as 16S rRNA cloning, but have yet to be cultivated in vitro. These bacteria are so difficult to culture outside of their biofilm habitat because they rely on metabolic cooperation and intercellular signalling with the community.

Sonia Vartoukian and William Wade of Queen Mary University of London, using their Don Whitley Scientific Anaerobic Workstations, have been shining a bright light into the dark niches of the oral cavity for years. They have identified a novel species in a new genus, Fretibacterium fastidiosum, through co-culture with other oral bacteria cultured in the anaerobic workstation. More recently, they were able to isolate five novel strains from subgingival plaque, using a combination of community culture with helper strains and supplementation with siderophores as growth supplements. The bacteria are surprisingly agile in adapting to changes in their co-dependent habitat, as long as they are provided with the signals and factors they themselves have lost the ability to synthesize. Over the course of up to 21 day culture of the samples, Vartoukian and Wade were fastidious about not exposing the cultures to air, using plates that were pre-reduced in the workstation’s anaerobic atmosphere and making sure to minimise time spent outside of the workstation. The Whitley Anaerobic Workstation makes it easy to work with sensitive cultures. The 10mm thick annealed acrylic, patented use of Anotox, rapid transfer airlock, and easy-to-use sleeve gassing system ensure a robust and strictly anaerobic atmosphere.


Image from the website of Yihong Li of the Department of Dentistry, NYU

Image from the website of Yihong Li of the Department of Dentistry, NYU


On the other side of the Atlantic, Microbiology International distributes the Don Whitley Scientific anaerobic workstation to North American groups researching the oral bacteriome in physiology and disease. Dr. Yihong Li at New York University Department of Dentistry uses his A35 workstation “to facilitate cutting-edge research in clinical microbiology, antimicrobial treatment evaluation, and infectious disease identification.” The A35 can accommodate up to 600 90 mm plates and features bare-handed access to a consistent and strictly anaerobic environment, reliably monitored by the Anaerobic Conditions Monitoring System. Dr. Li’s research on dental caries has shown that the anaerobic environment is essential for colonization by oral lactobacilli. His group’s large-scale studies of the diversity of lactobacilli associated with severe early childhood caries have demonstrated the necessity to provide a range of anaerobic and microaerophilic niche environments in order to capture the complexity of Lactobacillus variables.


Dr. Li’s group will be presenting new research on oral biofilms at the AADR conference.

Visit Microbiology International at  the AADR/IADR meeting in San Francisco on 22-25 March to experience anaerobic workstations for yourself! 

Interview with Dr. William Weiss from University of North Texas

Our US distributor Microbiology International carried out this in-depth interview with Dr. William Weiss, a Whitley Workstation user from University of North Texas. 

Dr. William Weiss is the Director of Pre-Clinical Services at University of North Texas in Fort Worth, working to develop animal models in infectious disease for the evaluation of new and novel therapies in antibacterial, antifungal and antiviral research. He has been using a Don Whitley Scientific DG250 and an A35 anaerobic workstation for about two decades.

Read more about his research on novel antibiotics for the treatment of Clostridium difficile infection here.

Q: What manner of specimens are you working with and which bacteria do you cultivate in the anaerobic workstation?

A: Here in the Pre-Clinical Services group, we are essentially a contract research organization, and the majority of our work in the A35 anaerobic workstation involves C. difficile. We are carrying out various research projects for different pharmaceutical companies, and biotechnology companies, here in the US, as well as Europe and South America. There are various experimental models for reproducing C. difficile disease, for example, the “gold standard” model involving the hamster, and there is also one that involves mice.

Basically, in this model, spores from C. difficile are introduced into the animal, and they colonise in the gut. C. difficile spores come from the environment and are ubiquitous, but because they are held in check by the normal gut flora, they never proliferate and they never cause disease. It’s only when patients are treated with broad spectrum antibiotics that healthy bacteria are destroyed and C. difficile then proliferates and causes disease. That’s why often, people going into the hospital and receiving multiple antibiotics can develop C. difficile disease.

Q: So what is the role of the A35 workstation in your C.diff. research?

A: The model we are using to test novel therapies designed to combat this disease depends strongly on the A35: we grow the C. difficile culture by streaking the frozen cultures onto appropriate media, incubate them in the A35 chamber at 0% oxygen, and then harvest the vegetative cells and treat them to form spores, which we store. The spores are then introduced into the animals, the animals are treated with a broad-spectrum agent, they develop the disease, and we try different forms of therapy. The end-points in terms of efficacy are increased survival, as well as the amount of C. difficile that can be found in the fecal pellets of the hamsters, or in the contents of the cecum. We process the fecal pellets or a cecal sample and plate it, then we place those plates inside the chamber to incubate for about 48 hours. An animal that might have the disease could have 6 logs of C. difficile in their gut, whereas one that has seen successful treatment, such as with vancomycin, the gold standard right now, might be reduced from 6 logs to 2 logs or even less. All that incubation is being done inside the A35.

Q: The A35 isn’t your only workstation though, tell us about that.

A: With C. difficile being a larger problem than it used to be, we are seeing a real uptick in the number of companies interested in it, thus explaining our need for the A35 workstation. The C. difficile in the environment is very hardy, because it can form spores, but in order to count the spores, they have to germinate into the vegetative state, and that’s what you need the workstation for. Prior to the A35, we had the smaller DG250 model, and at the time, when we were just working with some bacteroides, not a lot, it sufficed. But when we started working with C. difficile, the amount of studies and the type of studies we did really expanded. So at that time, we contacted Microbiology International since we needed a larger workstation in order to accommodate all those studies. The A35 is now our second Whitley workstation, but we are still using the DG250, too. We’ve converted the DG250 to a microaerophilic environment, because we do Helicobacter pylori work in there. It’s a facultative anaerobe, so when we need to grow up plates or process samples, we use that smaller workstation with a 5% oxygen mix.

Read the full interview here

Read more about Dr Weiss’ work here


Microbiology International at Anaerobe 2016

Don Whitley Scientific’s US/Canadian distributor, Microbiology International, will be at this years Anaerobe Society of the Americas (ASA) Anaerobe meeting. This biennial conference will be hosted at the Sheraton Nashville Downtown Hotel in Nashville, Tennessee. The event is running between July 11-14.

Anaerobe 2016 has a program full of speakers, presentations and poster sessions as well some fantastic social activities. Presentations feature a range of topics relevant to an audience that will include researchers, clinicians and technicians and the social events include a pre congress mixer at a local blues club, a wine and cheese drinks reception and a congress dinner.


The Microbiology International stand will feature a Whitley A35 Anaerobic Workstation. This workstation offers a capacity of up to 600 90mm Petri dishes and features a touchscreen system, enabling users to stay in control of all parameters and conditions. The A35 is also available with instant access ports and a rapid cycle airlock system, these options can improve working methods in the lab.

Also available on the stand will be the publication: An Introduction to Clinical Anaerobic Bacteriology. This guide, published by Don Whitley Scientific, enables readers to isolate and identify commonly occurring, clinically important anaerobic bacteria. With consultation from some of the most experienced people in microbiology, this is one of the most up-to-date reference guides available for the modern clinical laboratory. There will be multiple copies available on the Microbiology International stand, so make sure you drop by while supplies last!

Other publications available on the stand are flyers which detail clinically relevant gram-negative and gram-positive anaerobes. Like the Introduction to Clinical Anaerobic Bacteriology, these should assist clinicians in identifying relevant anaerobes.


Introduction to Clinical Anaerobic Bacteriology

Introduction to Clinical Anaerobic Bacteriology




Gram postive anaerobes

Common Gram-Positive Anaerobes flyer











Visit Microbiology International at ASA Anaerobe Nashville 2016 – Sheraton Nashville Downtown Hotel, Nashville, Tennessee  July 11th-14th 2016


Top Distributor Award 2014

Congratulations to the team at Microbiology International (USA), who sold more equipment than any of our other distributors last financial year, and have been awarded Top Distributor of the Year 2014.


Microbiol. Int

Don Whitley Scientific has enjoyed a mutually-rewarding working relationship and friendship with Microbiology International for over two decades, and we look forward to many more years of successful collaboration.