Molecular mimicry, food security, and seaweed might not seem related at first glance, but this video explores their fascinating intersections. mimicry is a natural strategy where one organism imitates another to gain advantages, such as with the king snake and coral snake. The video provides an example from the marine world involving the symbiotic relationship between the cleaner fish and larger fish, contrasting it with a predatory mimic that deceives larger fish for survival. On land, plants engage in a continuous arms race with pathogens, adopting advanced chemical defenses that resemble mimicry at a molecular level.

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Key Vocabularies and Common Phrases:

1. mimicry [ˈmɪmɪkri] - (noun) - The ability of an organism to copy traits from another for some advantage. - Synonyms: (imitation, replication, simulation)

The definition of mimicry is the ability of an organism to copy traits from an unrelated organism in order to gain some sort of advantage.

2. symbiotic [sɪmbaɪˈɒtɪk] - (adjective) - Involving interaction between two different organisms living in close physical association. - Synonyms: (mutualistic, cooperative, interdependent)

The cleanerfish is a small fish that forms symbiotic relationships with larger reef fishes.

3. elicitor [ɪˈlɪsɪtə] - (noun) - A molecule that triggers a response in an organism, especially in plants as part of their defense mechanisms. - Synonyms: (inducer, stimulus, activator)

On the plant's surface, receptors detect specific elicitor molecules.

4. effecta molecule [ɪˈfɛktə ˈmɒljukjuːl] - (noun) - Molecules released by pathogens to hijack a host's chemical defenses. - Synonyms: (effector, agent, influencer)

The pathogen in turn will respond by releasing so-called effecta molecules.

5. pathogen [ˈpæθədʒən] - (noun) - A bacterium, virus, or other microorganism that can cause disease. - Synonyms: (germ, microbe, infectious agent)

So has the arms race between plants and the pathogens that attack them.

6. polysaccharide [ˌpɒlɪˈsækəraɪd] - (noun) - A carbohydrate whose molecules consist of a number of sugar molecules bonded together. - Synonyms: (complex sugar, carbohydrate, glycogen)

The main component of seaweed and the main commercial product are their polysaccharides or their complex sugars.

7. texturizer [ˈtɛkstʃəraɪzər] - (noun) - A substance that improves the texture of a product. - Synonyms: (emulsifier, stabilizer, thickener)

These sugars are things like agar and alginate and kerogen, and they are used as emulsifiers and texturizers and binders in all sorts of things.

8. aquaculture [ˈækwəkʌltʃə] - (noun) - The rearing of aquatic animals or the cultivation of aquatic plants for food. - Synonyms: (fish farming, mariculture, pisciculture)

I think this might be just a thing that will put New Zealand's seaweed aquaculture on the global picture.

9. extracted [ɪkˈstræktɪd] - (verb) - To remove or take out, especially by effort or force. - Synonyms: (withdrawn, removed, obtained)

In my team, we have extracted a specific sugar called olvan from this seaweed.

10. propelling [prəˈpɛlɪŋ] - (verb) - Driving or pushing forward. - Synonyms: (driving, thrusting, advancing)

A few years ago, I was given the opportunity to come to New Zealand and lead a research team here...with the ambitious goal of propelling us to the frontline of this industry.

Molecular mimicry, Food security - and Seaweed - Marie Magnusson - TEDxUniversity of Waikato

Molecular mimicry, food security and seaweed. What on earth do these have in common? When you hear the word mimicry, you might picture something like this. I heard that this is a textbook example where the non poisonous king snake mimics or imitates the appearance of the poisonous coral snake. You can clearly see here in this drawing that I did with my 9 year old, which snake is the dangerous one. But it may not be so obvious if you were to meet them in nature. The definition of mimicry is the ability of an organism to copy traits from an unrelated organism in order to gain some sort of advantage. In the example with the snakes, the king snake benefits because predators will think it's dangerous and will avoid it.

Given I am a phycologist, which means I like algae and my favorite topic is seaweed. A marine example would be the cleanerfish and its predatory mimic. The cleanerfish is a small fish that forms symbiotic relationships with larger reef fishes. A man cleaner station, where this larger fish come in and hang still in the water column, allowing this small cleaner fish to come in and eat parasites from their skin and from their gills and even inside their mouths without trying to eat it. This is a win win situation where the cleaner fish gets a home delivered buffet and the larger fish they get improved oral hygiene. The predatory mimic, on the other hand, looks and behaves just like the cleanerfish. But instead of eating parasites, it will nip chunks of tissue off the larger fish. So here the mimic benefits because the larger fish, its prey, believe that it's actually harmless.

But let's return to the land and to plants specifically. Just like these previous examples have developed over evolutionary timescales, so has the arms race between plants and the pathogens that attack them. It's like advanced chemical warfare at the molecular level, where the shape and interactions, just like a lock and key of biomolecules, has driven the development of complex sensory messaging and defense systems in plants. These defense mechanisms, they occur both on the plant cell surface and inside the cells. On the plant's surface, receptors detect specific elicitor molecules. Remember that lock and key and these elicitor molecules can come from either the pathogen or from damaged plant tissue caused by pathogen activity. The detection of these elicita molecules kickstarts the plant's defense system in order to halt the spread and colonization by the pathogen. The pathogen in turn will respond by releasing so called effecta molecules. And these are designed to hijack the plant's chemical defenses in order to gain access to inside the cells. If this happens, the Plant's final line of defense includes localized chemical bleaching and cell death in order to take that pathogen down with them. Of course, this can backfire if too many cells die.

But importantly, plants that have been challenged by pathogens and survived, and where these illicit molecules have been detected, they are now more resistant to future attacks by pathogens, just like having an inoculation now. Unfortunately, pathogens and diseases they cause are a major threat to food security. A New Zealand example of this would be psa, a bacterial pathogen that devastated the New Zealand kiwifruit industry when it first emerged. Similar pathogens and their diseases affect important crops globally. In order to stop and to treat these pathogens and their diseases, a range of synthetic chemicals are used. And often these are based on heavy metals like copper or antibiotics. This might sound a little precarious, but these chemicals are really important. Without them, we could lose up to 50% of the harvest every year. That is 50% half of the fruit and vegetables produced lost or inedible due to disease. So not using these chemicals might mean doubling the cost at the supermarket checkouts or halving the number of families who can afford to buy fruit and vegetables. But still, there are concerns around both environmental and human health impacts from the use of these chemicals. And a lot of pathogens are developing resistance to these chemicals as well, which means that they are getting less and less effective. There are lots of strong drivers for developing novel, lower impact alternatives to protect our food security.

So let's talk about a solution. And it's time to return to the sea. And my favorite topic, seaweed. Like I promised, I've heard that not everyone is as excited about seaweed as I am, but perhaps after this talk, I will have converted a few of you, because seaweed are gorgeous and really fascinating and also very useful. So because we people, we like to sort and group things into little boxes, we typically sort seaweed based on their pigmentation into red, green, and brown. And we often talk about them as if they are a homogenous group and as if they are similar to land plants, which, in fact, they are not. Seaweed lack all the defining features of terrestrial plants. So. So they don't have true roots or stems or leaves or flowers or fruits. And although green seaweed are reasonably closely related to land plants on the evolutionary tree of life, brown seaweed, they belong to a completely different biological kingdom. And so, in a way, green seaweed and brown seaweed, they are as different to each other as a salmon is to a jellyfish.

A lot of people recognize their Seaweed, mostly from seaweed salad or the nori that holds your sushi together. But the main component of seaweed and the main commercial product are their polysaccharides or their complex sugars. These sugars are things like agar and alginate and kerogen, and they are used as emulsifiers and texturizers and binders in all sorts of things, from textile printing to gastric acid reflux control, or in meat canning processing, or as an ingredient in ice cream and dessert puddings, or your shampoo and toothpaste. We get the seaweed for all these products through farming. In fact, seaweed farming is a multi billion dollar global industry. And here in New Zealand, we have one of the largest economic exclusive zones in the world and over 1,000 species of seaweed. And many of these are completely unique to New Zealand and don't grow anywhere else in the world. And so we have so much potential. But we are quite late to the party, and our seaweed farming industry can only really be described as emerging. And so this is where my team and I come in. A few years ago, I was given the opportunity to come to New Zealand and lead a research team here at the University of Waikato with the ambitious goal of propelling us to the frontline of this industry. No pressure.

And while we may not be global leaders yet, we do find some pretty cool seaweed. I will show you a video of some seaweed that we grow. This is from inside one of the ponds at our pilot facility at the university. And this seaweed is called Ulva. It's very pretty. It's my favorite, and it's also very useful. And this brings us back to those sugars. So just as fascinating as all those daily use products that require seaweed sugars is that some of these sugars are in fact, similar in shape to those lock and key shapes I spoke of earlier, those elicited compounds that kickstart the plant's natural defense to threat. And so this brings us back to the very beginning, that concept of molecular mimicry. So here we have an opportunity to use seaweed sugars to mimic the plant's natural response to threat, and in doing so, start to elicit those plant defense mechanisms without exposing the plant to actual disease. And if you remember, these elicited products, they work as an inoculation for the plant, so they are more resistant to future attacks by pathogens. And this means that we will be able to use less of those potentially harmful chemicals that are needed for treating disease.

So in my team, we have extracted a specific sugar called olvan from this seaweed that we have farmed at scale and apply this to a range of crops in glasshouse trials, including tomato and kiwifruit, with really promising results. We have shown that our ovans prevent disease at low application rates and that ovens with different shapes have different activity. This is great news because it means we can use that information to modify these shapes further and improve that molecular mimicry and drive activity up and make them better. We are in the early stages of this research and there are a few pieces of the puzzle left, but it's super exciting. If we can demonstrate that our results translate well to the field. We will have a New Zealand farmed and produced seaweed illicit product that can pass organic labeling and provide a novel, gentler tool in the toolbox to protect our food security. The implications of not doing something like this and keeping to the status quo includes continuing to spray heavy metals and antibiotics on our food with that risk of increasing pathogen resistance to these chemicals and further future losses.

So what can you do, you might wonder? Well, if you are in legislation or policy, you can keep seaweed on the agenda. There's a lot you can do to help. If you are a primary producer with access to seawater, consider seaweed as your next crop. There are oceans of opportunity here. And if you are a horticultural grower or just have a green thumb, keep a lookout for New Zealand produced seaweed illicit products in the future to protect your crops. And finally, we only recently got funded to keep going with this research, which is fantastic. And I think this might be just a thing that will put New Zealand's seaweed aquaculture on the global picture.

INNOVATION, SCIENCE, GLOBAL, MARINE BIOLOGY, FOOD SECURITY, SEAWEED FARMING, TEDX TALKS