Navigating Changes, Crossing Borders, and Solving Global Problems: An Interview with Plant Physiology Associate Editor Andrew Hanson, PhD

Andrew D. Hanson is a professor at the Horticultural Science Department; University of Florida, in the USA. Andrew studied plant biology with a focus on medical biochemistry in the United Kingdom for his undergraduate degree. After completing his PhD, he secured his first industry job with a company, gaining valuable experience. Throughout his career, he has worked in the UK, France, Canada, and the USA.

He specializes in synthetic biology, biochemistry, and plant physiology, but in a Crop Science or Horticultural environment. This allows him to focus on addressing pressing issues such as climate change and sustainable food production for a growing population.

 In this interview, we talk about careers in companies and universities, changing countries and fields, how to contribute to acute problems with basic science, and overlooked topics in plant biology.

Careers in Companies and Universities – and Learning About Them

 Henryk: What part do you enjoy the most about being involved in science and working at a university as a professor or as a scientist in general?

Andrew: First and foremost, the opportunity to be useful in learning new things and helping other people to learn new things and to build their careers. I emphasize useful, because I work and have worked in universities almost always in a horticulture or crop science department, which are connected to real problems and real users. They are not only about abstract knowledge but also about knowledge that could be used. I think it is a privilege to be able to work in basic research, but in connection with people who deal with the problems that are out there. Those problems are only going to grow. I also think it is a real privilege in universities to be, at least in principle, paid to think about what the problem is that you should work on. I mean, you are constrained by what is fundable, but there is some agency there.

In my early career, I worked for a cereal company in the UK. I was partly trained in my PhD with a sugar company, a very large one that still exists. There I learned a lot about the interface between basic knowledge and what actually gets used. Those were very precious years and I thoroughly recommend that experience to people who want to become academics. Do something else as well, because it really opened my mind.

H: I have the impression that many people assume that life in companies is easier compared to academia. What do you think about that?

A: I think it is impossible to generalize because industry is not a monolith. It is a whole ecosystem of companies, from basically single-person startups all the way to international behemoths. I would make a couple of generalizations. In universities, it is about establishing yourself as an independent investigator. It is really about you, your group, and your career. That is how the promotion and tenure system works. Whereas in a company, it is more about delivering the product, working with people in a team to do it, where the actual individual career is not the objective in itself. That ability to cooperate on a common objective exists in universities too, but generally, that is not the way you get tenure. At least in the systems that I know you have to establish yourself as an individual independent force.

There is an economic difference between companies and universities, which is that there is a very large pool of people who want to be professors. It is a buyers-market: the expectations can be very high because there are so many people who want your job. Universities are well-intentioned, they want life to be good for their faculty, and they want to retain them. But they are not as conscious of the need to attract and retain people, I would say as companies are because the company environment is much more mobile, you can up and leave, and in universities, you can’t up and leave so easily. I think it is a delusion that companies are easy to work for, but I think they tend to try to retain people and do not want to turn their lives into 70-hour-a-week hells that will drive them away. They are much more interested in making life tolerable, at least, preferably more than that. Universities today are not so concerned with that issue. They let people work as much as they want, or as much as they have to. But in startups, I mean, my goodness, that’s absolutely not stress-free. It is an extremely demanding business. I know some people who have gone into that sector and started small companies and I really take my hat off to them. So there is no one answer.

H: Should the barrier between academia and industry be more permeable? The current system in Europe is largely one-way, once you leave academia it is very hard to get back into it.

A: The statistics are that in bioscience training, and plant science is a subset of that, about 85% of people who get doctoral degrees will not work in a university setting, and even fewer of them will be faculty. Industry and other non-university careers are not alternatives. They are the mainstream. There is a considerable lack of understanding within universities, both the faculty and the people that they train, of what the opportunities out there are.

I think it is really important to start having institutional mechanisms to introduce people early in their career steps, PhD or postdoc training, to what those opportunities are. That involves organizing webinar activities for example. The American Society of Plant Biology is getting into that and I am trying to help them to get even more into it: bringing in industry scientists, making them visible and organizing informational interviews, where early-career researchers get to talk to industry people informally about what they do, and internships.

McMaster University in Canada is a good example. They have undergraduate degree programs that involve time in a real work environment. Compared to bioscience faculties, other parts of universities, like engineering faculties, have a much, I would say, closer relationship with industry. and they also do internships. I think we should move in that direction. I have a current grant proposal that has a very large element of that in it. I want to do what I say.

If you leave a university and go to a company, it is not so easy to come back in unless you have published. Actually, when I was in the company I published with a colleague and on my own. People I know who have made that transition have done exactly the same. They had much longer times in companies than I did, but they remained engaged with the university sector and did all the things that professors do, they were editors in journals, they went to meetings, they talked about their work quite freely. It is possible to do that, but it is still quite rare. That means that the majority of people in universities, the faculty, have never been anywhere else but a university. I mean, the somewhat exaggerated way of saying it is that they have been in school all their life. Therefore, however well-meaning they are, they really do not have the contacts and the mindset to make the connections and to show people what is out there. There are some people, I think an increasingly small proportion, who see academia as the only honorable way for a scientist to pursue a career and they remain skeptical, and even I could say scornful, of industry, which is terrible, but it is a minority of people.

The Value of Changing Countries and Fields – “Pay Attention to Other Areas”

H: I noticed in your CV that you have been in France and in Canada. What are the most valuable points you took from staying in a foreign country and immersing yourself in different cultures? How did it affect your personal and professional life?

A: I think, just like music, it adds another dimension to your thinking and even to your person. Stepping out of your own culture and your own familiar contacts, particularly into another language, really does change the way you think. It adds another dimension to your way of thinking and to your social skills as well. You make fewer assumptions about what the people around you think. Especially if you can do that early, it is a tremendous gift. Even to children, I mean, to give them exposure to another culture while they are still very malleable. I appreciate a lot my parents who allowed me to go on an exchange visit to Bordeaux in France when I was about 12 years old. I believe that this experience was formative, it encouraged me to think, “Hey, I can do this; I can go and function in another language.” I really respect Europeans in that regard. When I worked in Europe, I would find people who spoke four languages, and the first three they spoke pretty much perfectly. I had two and the second one was not that great.

H: Something that interested me, is that you are a scientist who has been involved in many studies that are not only focused on plants but also on other organisms: What can plant-focused scientists learn from other fields like biology on fungi or bacteria, and vice versa?

A: The plant world, plant sciences really, has some unique features because of the special nature of plants. Higher or lower, they operate in a different way to heterotrophs. But a great deal of plant sciences actually are very, very dependent, almost derivative, of other fields. The ideas for biochemistry come out of mammalian and microbial biochemistry. The ideas for molecular genetics similarly come through those fields, particularly prokaryotes initially. So in order to be a well-rounded and well-equipped plant scientist, you have to pay attention to these other areas. It is even better in some ways to be formed in one of those other areas before you come to plants. Because plants are—I do not want to sound too negative—but they are kind of intellectually downhill from a lot of the places where the ideas actually got started. Some very influential plant scientists started in microbiology; Christopher R. Somerville is an example. He was a microbial geneticist initially. Other people have started more in chemistry. These are both very good places to begin, because they equip you with a collection of broad tools. My undergraduate degrees were in what used to be called botany, but it was a joint major with medical biochemistry, so I always came at biochemistry with a kind of medical biochemistry mindset. That has been helpful, and there have been plenty of other mammalian biochemists who have moved toward plant sciences.

H: But do you think that there’s also something that other fields can learn from plant biochemistry?

A: Well, I can tell you that medical biochemistry pays very little attention to plant biochemistry, for obvious reasons. Is there two-way traffic with microbes? Well, yes, at the level of the photosynthetic organisms, surely, that is a very substantial flux of both directions of knowledge and understanding. Otherwise, plants are quite unique. I mean, what else has roots, leaves, or xylem? However, with that said, we are focusing much more on microbiomes, in the medical as well as the plant world and the services that microbiomes may provide to the larger organism. There are probably many more opportunities for dialogue now, which has been rather compartmentalized. People have been studying the soil microbiome and microorganisms for a very long time. There is beautiful biochemical and genetic work going back to the 1930s and 1940s, but it is pretty much divorced from the plant. Plant physiologists tended to grow plants in hydroponics, which certainly have a microflora, but it is a fairly depauperate one compared to what it would be in the soil. Nowadays we are asking a lot more complicated questions involving how there is a sort of interplay between these partners in a microbiome.

Basic Research and its Contribution to Acute Global Problems – “Back-of- Envelope Calculations”

H: How can or is basic research contributing to solving acute global problems, like climate change, or global hunger? How can people involved in scientific communication contribute to clarifying, and also supporting, basic research?

A: Well, there is a lot to unpack there. Let me give you a sort of philosophical answer on how basic research can contribute to solving big problems. There is a wonderful analogy that I learned from the late Yoash Vaadia, an Israeli-American scientist—an exceptional individual—who originally set up the Binational Agricultural Research and Development (BARD) program. The analogy is the following: It is like a diffusion gradient. If you do basic research, you are driving technology development or improvement by steepening the gradient, you are adding to knowledge. On the other hand, you can drive technology development, or facilitate it by increasing the conductance to the flow of knowledge from basic research. That is what we call in the United States extension, and what everybody calls teaching. So, you have these three activities: basic research, teaching, and extension, and they need to work together. As you might know, that is the so-called Land Grant Philosophy of the major US public agricultural universities, where they have this three-part philosophy of teaching, research, and extension. The basic scientists increased the steepness of the diffusion gradient if they are in the same department, the same institution, they work and teach themselves, and they are also working with extension people to move the knowledge outward. That is the philosophy about teaching, research, and extension.

I would say the main action we have now in terms of budgetary allocations in funding agencies is the redirection to acute global problems, like food and climate security. Some of the current action in both those areas is long-range research to increase photosynthetic carbon fixation or to decrease the water price that is paid for carbon. Underneath that, there is work on carbon capture and storage in plants and soils and on biological nitrogen fixation to replace the Haber-Bosch process, generally on nutrient use efficiency, because we have a problem with phosphorus and potassium as well as nitrogen for modern agriculture. And of course, stress resilience mechanisms, all those areas are very active in basic research now, and that is good to see.

I want to add a couple of more things about basic research and what you decide to do in basic research. There is something called Fermi problem thinking. Another name for it is “back-of-envelope calculations,” which are very useful in choosing research goals. They are surprisingly often not done, including by governments and funding agencies, and least of all by researchers. What you do is ask, “How big is the problem? How much could a possible solution contribute to solving the problem?” In other words, how scalable is it? That kind of easy calculation that you can make armed just with Google and a calculator about what is possible and what is not, and what the scale of the possible is. I really would encourage people to learn how to do that and apply it to the problems that they think they want to work on. Because it is unfortunately true that institutions and their leadership—that is, a higher level of organization than the individual researcher, particularly the relatively junior researcher—may not make these calculations the way they should. So you ask yourself, for example, “Can we increase the level of recalcitrant polymers in the roots, sequester more carbon in the soil, and reduce the level of CO2 in the atmosphere?”

Well, if you make back-of-envelope calculations, informed ones, but ones you can make in a few hours at the most, how much of that CO2 could you put in the root? How long would it last in the soil, because even recalcitrant compounds are broken down? The more the organic carbon content of the soil goes up, the faster it is broken down. So, it is kind of asymptote. One cannot indefinitely keep increasing the organic content. So how long? How long will it last in the soil? How much could you put in the root? What would the weight or carbon stored per acre be? How much agricultural land could you implement it on? Then, what would that do to carbon drawdown? We have made those sorts of calculations and they are in an update in Plant Physiology that came out at the end of last year. Something could be done, but it is really quite small. You will search in vain for calculations of that sort in the press releases and TED talks that are given on this topic.

It is, to me, honestly, a vital skill for early career people to get to know how to do back-of-envelope calculations. It is on that basis that you might make career decisions as to, for instance, which company you are going to go and work for, or which grant program you are going to apply to. Because you will have a picture, which might even be better than the people running the company or running the grant program, of what is really worthwhile and what its limits are. Another example: the Haber-Bosch process for nitrogen fixation, which is an incredible gift to humanity. Do you happen to know how much of the human population is basically sustained by Haber-Bosch nitrogen fixation? In other words, if we took it away tomorrow, how much of the population could we not sustain?

H: I could imagine that is a lot of people.

A: You can find this information in many places, for example here. It is half of the population. As far as the nitrogen budget of the planet goes, for terrestrial nitrogen fixation, the Haber-Bosch process is larger than all the natural processes put together now and has been for many years, so we have really altered the nitrogen cycle and have become dependent on Haber-Bosch. How much of that could you replace with organic manure? Some, but the organic manure requires nitrogen in it. Where did that nitrogen come from in the first place? It has to come from biological fixation if it is not coming from Haber-Bosch. See where I am going? It is that kind of thinking and arithmetic that I think most undergraduates are not able to perform; few graduate students would have been exposed to that way of thinking either. In engineering, they often would, but in biology, not so much.

Synthetic Biology as a Possible Answer – “Rethinking the Thing From the Ground Up”

H: Do you think that synthetic biology can answer some of these problems or aid to solve some of these, although it may not be that easy?

A: I think we need to start from the position of what will come in the next 30 to 50 years. Your career, for example, will unfold in that window. These years will be vastly different to the last 50 years. Many things will change and one of the most important things that synthetic biology in particular, and basic research in general, can do is to start radically reimagining and trialing ways we do things now in a different fashion. The example that I hold up the most, although it is very futuristic, comes from the late Aaron Bar-Even, with whom I was privileged to work a little, and call a friend.

That is the so-called one-carbon bioeconomy, where you use renewable power, air (carbon dioxide), and water, to produce simple energy-rich molecules like hydrogen, formate, and methanol. Then you feed those to microbes and generate your fuels, feedstocks, and food. Now, that is very futuristic. It depends on abundant renewable power, which is a whole other problem, and we can talk about whether we are going to have that, but it is really rethinking the thing from the ground up. That is the kind of thinking that we will need in the coming decades.

Synthetic biology specializes in reimagining how life could be—subject to the thermodynamic and kinetic constraints, which are inevitable and built-in—but not trapped in the way that evolution actually took the path that it did. It branches out into what is possible, not what is actually in existence. It tries to achieve some approximation to that alternative, for example, by taking enzymes that already exist and evolving them experimentally, to do a better job of something that enzymes only do a little bit of now but something that would reconfigure carbon fluxes. That is exactly what this kind of one-carbon bioeconomy does.

Another more, I would say, tactical thing—that first one is strategic—is that we need to mesh synthetic biology, particularly directed evolution, protein engineering, and genome editing, with modern plant breeding, so-called precision breeding. We now have the capability to modify a small number of target enzymes and proteins by directed evolution or by protein engineering. We can design or evolve different versions of an existing enzyme, and then we can use genome editing to make those changes in the genome. That is where you have the interface with modern breeding. You have really functionally expanded the gene pool for breeding. If you do that, and there is no transgenesis involved, you are not slamming a gene somewhere into the genome in a somewhat random fashion with a marker, which you might not want to have. This is much more precise. It does interface very well with modern precision breeding where people are manipulating known genes, not just traits. I think that that dialogue as to how to interface synthetic biology and protein engineering with modern plant breeding needs to develop faster and farther. The wonderful technology that is the interface between them is genome editing.

Overlooked Topics in Plant Biology – “It’s the Metabolism Stupid

H: You published recently in a collaborative effort that plant respiration is an overlooked topic. Do you think that there are other topics in plant science that are dangerously overlooked, comparable to what you published on plant respiration?

A: I think that root biology in general, but especially exudation from roots, now that we are so interested in microbiomes, is overlooked. The amount of exudation from roots is a giant hole in plant carbon budgets; we do not know how much goes out and we do not know reliably in what form it goes out. This is what sustains the root microbiome, on which we are now planning to rely more, to fix nitrogen and for other functions. If you have so much of a gap in knowledge, then it is really an asymmetry in research that so much plant research on productivity goes toward photosynthesis whereas not much goes toward respiration, and even less goes toward root biology of this kind. There is a reasonable amount of work on more developmental aspects of root biology, of course, but this role in the carbon budget is quite overlooked. I emphasize that an understanding of root carbon output will enable essential estimates of what we can hope the microbiome can do for us. The microbiome has got to be fed by something and it is basically fed by current photosynthate plus relatively recent previous photosynthate in the form of dead biomass. It is all photosynthate.

You asked what else is overlooked. I think we started to talk a little bit about this at the beginning about how valuable it is to have some background in chemistry, because there is a wonderful quote that we used in an article a few years ago (doi: 10.1042/BST20160073) from Alexey Golubev who is a brilliant Russian biological chemist. He said, “Nothing of chemistry disappears in biology.” The history is roughly this: Early metabolic biochemists mapped out with biochemistry and genetics the pathways that we learned in the textbooks. They all knew chemistry, including thermodynamics. In other words, that first generation knew what side reactions could happen. They knew what was possible and what was not. The second generation, which was people of my age, we focused more on biochemical pathways. We were learning the pathways, but we were not really learning the underlying chemistry and the other possibilities that nature did not explore. And then, the next generation after that learned genes and regulatory networks. So we become increasingly divorced from the underlying physical chemical realities. I want to give you a quote that is really worth remembering; it comes from an article by Victor de Lorenzo, who is an amazing Spanish microbiologist/ synthetic biologist. It is from a little article called “It’s the Metabolism, Stupid,” which is a play on a quote by President Bill Clinton, who once famously said, “It’s the economy, stupid.”

This is the quote from Victor: “The interplay of DNA and metabolism is, in my view, akin to that of politics and economy. Both realms drive their own autonomous agendas and obviously influence each other. Whether one likes it or not, it is economy that ultimately determines the viability of any political move. By the same token metabolism, that is the economy of living systems, frames and ultimately resolves whether a given genetic program already existing, knocked in by horizontal gene transfer, or engineered, can be deployed or not.”

It is a profound vision of how manipulating DNA, particularly in synthetic biology, putting in elaborate programs, is all dependent on the underlying energy economy, which is metabolism. And it is also its ability to deliver intermediates, which are materials. We have become somewhat divorced from that. I think that is why it really helps to be able to think back toward what are the physicochemical underpinnings of life when deciding what you might be able to do with it.

H: As we are finishing, is there something you want to talk about?

A: Well, it would be a reprise of the value of changing fields, the professional and human value of it. In academic circles, changing fields has historically not been the best career choice. And I think that may be changing as we enter a more complicated world, in which narrow specialist knowledge is really important, but it has got to be connected to other things if we are going to make an impact on the problems that we are now facing big-time. There is a wonderful quote from the Greek poet Archilochus, which is pretty well known, and it is: “The fox knows many things, but the hedgehog knows one big thing.” Now, it used to be thought that it was more important to know one big thing, in other words for a scientist, particularly an academic one, to be the hedgehog. It is now turning in a different direction because that fox has a better toolkit to deal with the problems. My thought is: It is better to be a fox than a hedgehog no matter what the university is telling you about specialization.

About the author

Henryk Straube is a postdoctoral researcher in the group of Fernando Geu-Flores at the University of Copenhagen, Denmark; fascinated by the intricacies of metabolism. He obtained his PhD in 2022 in plant biochemistry from the Department of Molecular Nutrition and Biochemistry of Plants at the Leibniz University of Hannover, Germany, under the supervision of Prof. Dr. Claus-Peter Witte and Dr. Marco Herde. He used a combination of analytical chemistry, biochemistry, and molecular biology methods to study nucleotide metabolism. Henryk currently researches biosynthesis pathways of anti-nutritional compounds in Legumes, with the aim of improving their use as protein sources. He is an assistant features editor of Plant Physiology for the term 2023-2024.