UNews - Agriculture and Agri-Food Canada

Improving animal nutrition and food safety at heart of research study published in Nature Microbiology

trevor.kenney — Tue, 23 Jan 2018 17:46:46 +0000

As the world grapples with the big problem of feeding 7.6 billion people, ��Ѹ��Դ��߿�Ƭ of Lethbridge adjunct professor Dr. Wade Abbott of Agriculture and Agri-Food Canada and his team have detailed the smallest of metabolic reactions with the goal of improving food security, food safety and animal nutrition.

Drs. Wade Abbott (pictured) and Steve Mosimann, along with a trio of former U of L students, detail processes in the human gut microbiome.

Abbott and his group, which includes the Institute for Cell and Molecular Biosciences at Newcastle ��Ѹ��Դ��߿�Ƭ, UK, Dr. Steve Mosimann of the U of L’s Department of Chemistry & Biochemistry and a trio of former U of L students, have been looking at prominent bacteria (Bacteroides) that thrive in the human gut microbiome, and detailing what glycans (carbohydrates) they eat on our behalf and how these processes take place, step-by-step. Understanding this, Abbott says, creates opportunities to manipulate the microbiome and possibly enhance food digestibility.

“It’s not enough to know what genes are present in the microbiome, we need to know what these genes do,” he says.

His group’s latest paper on this subject was recently published in the prestigious journal Nature Microbiology.

U of L alumnus Benjamin Farnell (MSc '14) at work in the lab.

“Understanding how different glycans are put together and then how they are taken apart is really what we are trying to get at with this study. And while there have been several papers written about similar processes in recent years, usually they are dealing with one sugar, one pathway, and trying to understand how that pathway works. This paper looks at how different pathways work together to digest a very complex network of plant cell wall sugars called pectin.”

Nature is the world’s most cited interdisciplinary science journal. Abbott was part of a group of researchers who made headlines in 2015 by discovering a strain of bacteria in the human gut that had evolved to the point where it could break down complex carbohydrates found in yeast. One of his students at the time, Richard McLean (BSc ’14, MSc ’17), also contributed to this latest paper that appears in the sister journal Nature Microbiology, along with Benjamin Farnell (MSc ’14) and Kaitlyn Shearer (BSc).

“We’re looking at how we can help animals digest feedstocks better, how we can improve their performance by using agricultural residues for growth promotion, and how we can improve food safety,” says Abbott. “It’s looking at ways to try to release more nutrition from complex glycans now that we know what bacteria and enzymes are required to do that.”

Farnell took the lead in mapping out one of the four complex pathways detailed in the paper, following enzymes as they catalyze reactions along the way and how they work together.

“When he started, we believed this pathway was involved but didn’t know what any of the proteins did,” says Abbott. “He systematically went through and looked at each protein independently and then put them all together, recreating the pathway. It was quite a nice piece of research and thesis that he contributed.”

Abbott says that with a renewed interest in environmental sustainability, a great challenge is trying to improve food productivity through natural processes. Harnessing the work done by bacteria in the gut in a manner that will improve animal nutrition is one way to approach the problem.

“Finding sustainable alternatives that really optimize how the microbiome works would be a great advance,” he says.

By mapping the pathways and better understanding the role of proteins and how they interact with one another in the microbiome, researchers are that much closer to enhancing food security and safety for an ever-growing population.

Zebra chip pathogen found in Western Canada for the first time

caroline.zentner — Wed, 18 Oct 2017 21:17:56 +0000

For the first time, evidence of the zebra chip pathogen has been found in potato fields in southern Alberta, but the ��Ѹ��Դ��߿�Ƭ of Lethbridge’s Dr. Dan Johnson cautions against panic.

Dr. Dan Johnson

“So far, the zebra chip pathogen has appeared in only small numbers of potato psyllids,” says Johnson, a biogeography professor and coordinator of the Canadian Potato Psyllid and Zebra Chip Monitoring Network. “The number of potato psyllids in all Alberta sites is very low and many sample cards have found no evidence of the potato psyllid insect. Zebra chip does not normally become a problem unless the potato psyllids are found in much higher numbers than are currently being found in Canada.”

An infected potato psyllid insect carries the Lso (Candidatus Liberibacter solanacearum) pathogen that can cause zebra chip disease in potato crops. Zebra chip has affected potato crops in the United States, Mexico and New Zealand and caused millions of dollars in losses. Potatoes with zebra chip develop unsightly dark lines when fried, making affected potatoes unsellable.

DNA testing for Lso was conducted in Dr. Larry Kawchuk’s lab, Agriculture and Agri-Food Canada, Lethbridge, from psyllids found on sampling cards in Johnson’s lab at the U of L. The first detection of Lso came from sampling cards collected at one site south of Highway 3. Johnson and his team subsequently increased the intensity of their sampling.

“A week later, potato psyllids from a second site north of Highway 3 also tested positive,” says Johnson. “This indicates it’s likely that we have a widespread incidence of Lso at a very low level instead of a single random arrival or importation.”

The team will continue to collect samples to determine when and if the number of psyllids with the pathogen decline. Potato psyllids, free of Lso, have been found in at least two greenhouses, where they can infest peppers and tomatoes. Johnson and his colleagues are considering the possibility that psyllids imported on plant material could have transferred Lso to the resident potato psyllid population.

While growers and managers can be reassured the numbers of potato psyllids and the incidence of Lso are currently low, Johnson has several recommendations.

Monitoring for potato psyllids near the collection sites where Lso was detected should be increased.

Additional monitoring techniques, such as nets, vacuums, and examining nearby vegetation, should be undertaken during and after harvest to detect overwintering potato psyllids.

Plant samples, including harvested potatoes, should be tested from the sites where Lso was found.

Managers should be made aware of the need for monitoring stored potatoes.

The monitoring for natural enemies of potato psyllids, such as minute pirate bugs and ladybird beetles, should continue in an effort to determine to what extent they could reduce future potato psyllid numbers.

The Canadian monitoring program began in 2013 in cooperation with Scott Meers, an insect management specialist with Alberta Agriculture and Forestry. The research and monitoring network is supported by Alberta Agriculture and Forestry, Agriculture and Agri-Food Canada, Growing Forward 2 (a federal-provincial-territorial partnership), the Canadian Horticultural Council and the Potato Growers of Alberta.

Ongoing monitoring program finds potato psyllids but no evidence of bacteria that causes zebra chip disease

caroline.zentner — Tue, 01 Aug 2017 18:13:56 +0000

��Ѹ��Դ��߿�Ƭ of Lethbridge biogeography professor Dr. Dan Johnson and his team have been monitoring Prairie potato fields for the past few years, looking for evidence of the potato psyllid insect and a bacterium it can carry that can lead to zebra chip disease in potato crops.

“We found hundreds of potato psyllids last year, but we have found under 10 so far this year and none have the bacteria that cause zebra chip,” says Johnson, who coordinates the Canadian Potato Psyllid and Zebra Chip Monitoring Network.

DNA testing for the bacteria is done in the Larry Kawchuk lab at the Lethbridge Research Centre, where Johnson is also a visiting scientist. Zebra chip has affected potato crops in the United States, Mexico and New Zealand, causing millions of dollars in losses. Potatoes with zebra chip develop unsightly dark lines when fried, making affected potatoes unsellable. The pathogen was found by researchers in Idaho as early as May this year, says Johnson. Given Alberta’s potato industry is worth more than a billion dollars alone, scientists and field workers want to ensure the province’s and Canada’s potato fields are being monitored.

At the end of last summer, Johnson found potato psyllids in Saskatchewan and Manitoba, thanks to cards collected and sent by network members there. This year, nearly 50 fields in Alberta are being monitored every two weeks and sometimes more frequently. Slightly sticky cards are placed on stakes in the fields and later examined under microscopes. With the expansion of the Canadian monitoring network, the researchers can map locations where the psyllids are found and compare their numbers to weather patterns and natural enemies of the pests.

Johnson and his team have produced a network newsletter with a colour photo guide so growers can more easily watch for the stages of the potato psyllid.

The Canadian monitoring program began in 2013 in cooperation with Scott Meers, an insect management specialist with Alberta Agriculture and Forestry. No psyllids were found in 2013 or 2014 and small numbers were detected in 2015 and 2016. That none have carried the bacteria that leads to zebra chip is good news, says Johnson.

The research and monitoring network is supported by Alberta Agriculture and Forestry and Agriculture and Agri-Food Canada, Growing Forward 2 (a federal-provincial-territorial partnership), the Canadian Horticultural Council and the Potato Growers of Alberta.

��Ѹ��Դ��߿�Ƭ of Lethbridge students have also been involved in the project, including, Christian Sapsford (BSc '17), Qing Xia, a graduate student studying the effect of weather and climate on the potato psyllid, Celeste Barnes, a graduate student who provided GIS and mapping collaboration and Mahsa Miri, a graduate student in New Media who assisted with the newsletter and brochures.

Beer and bread yeast-eating bacteria could open door to better health in both humans and livestock

trevor.kenney — Thu, 08 Jan 2015 16:36:35 +0000

It turns out that eating fermented food and drink, including beer, for the past 7,000 years has led to the evolution of bacteria that may hold the key to strengthening the immune system in both humans and livestock.

Dr. Wade Abbott, standing, and master's student Richard McLean, contributed to the groundbreaking international study.

A team of international researchers, led by Harry Gilbert of Newcastle ��Ѹ��Դ��߿�Ƭ, Eric Martens of the ��Ѹ��Դ��߿�Ƭ of Michigan, and ��Ѹ��Դ��߿�Ƭ of Lethbridge adjunct professor Wade Abbott of Agriculture and Agri-Food Canada (AAFC), has discovered that certain strains of bacteria in the human gut – Bacteroides thetaiotaomicron (Bt) – have developed a taste for yeast.

Publishing their findings in Nature the world’s most cited interdisciplinary science journal, the team of researchers say that the discovery of Bt’s ability to break down complex carbohydrates could accelerate the development of prebiotic medicines to help humans suffering from bowel problems and autoimmune diseases and potentially improve animal health and production.

A prebiotic is a nutrient that feeds beneficial bacteria and is typically a carbohydrate that we cannot metabolize. The ability of these microbes to degrade the almost impenetrable wall of complex carbohydrates surrounding yeast cells, known as mannan, is significant.

“Conversion of indigestible carbohydrates, such as yeast mannan, into beneficial molecules for their host has been associated with combating intestinal diseases, promoting correct immune responses and helping to maintain healthy tissues,” says Abbott, who teaches chemistry and biochemistry at the U of L.

By identifying the complex machinery that targets yeast carbohydrates, researchers now have a better understanding of how our intestinal tract can obtain nutrients from our diet. For humans, this discovery could mean the development of new prebiotic medicines and treatments against yeast infections and bowel diseases such as Crohn’s.

“People are very interested in developing dietary regimes where good bacteria are of benefit,” says Gilbert, in a Newcastle ��Ѹ��Դ��߿�Ƭ news release. “When you have certain bacteria dominant in the gut, these microorganisms can produce molecules which have health promoting effects.”

Understanding the role of intestinal bacteria in livestock could result in next-generation innovations – such as alternatives to antibiotic growth promoters – potentially improving animal health and production, and thus positively impacting the safety, sustainability and profitability of Canada’s agricultural sector, says an AAFC release.

The study also involved U of L master's student Richard McLean (BSc ',14) who was given the opportunity to work on the project as an undergraduate student while taking an Applied Studies course with Abbott.

“We needed to crystalize an enzyme in order to solve its structure,” says Abbott of McLean’s research focus. “Three other researchers had been working previously at trying to crystalize this protein, including myself, and for some reason, he had the knack and was able to pull it off and we were subsequently able to get a structure out of it.”

The entire research team contributing to the study represents the following institutions: Newcastle ��Ѹ��Դ��߿�Ƭ (UK); ��Ѹ��Դ��߿�Ƭ of Georgia; ��Ѹ��Դ��߿�Ƭ of Lethbridge; ��Ѹ��Դ��߿�Ƭ of Michigan; ��Ѹ��Դ��߿�Ƭ of York; ��Ѹ��Դ��߿�Ƭ of Melbourne; ��Ѹ��Դ��߿�Ƭ of Kansas; Oxyrane (Belgium); ��Ѹ��Դ��߿�Ƭ of Victoria; United States Department of Agriculture; and Agriculture and Agri-Food Canada.

UNews - Agriculture and Agri-Food Canada

Improving animal nutrition and food safety at heart of research study published in Nature Microbiology

Related Topics

Zebra chip pathogen found in Western Canada for the first time

Related Topics

Ongoing monitoring program finds potato psyllids but no evidence of bacteria that causes zebra chip disease

Related Topics

Beer and bread yeast-eating bacteria could open door to better health in both humans and livestock

Related Content

Journey to academic success doesn't always follow same path

Related Topics