Pushing boundaries – Study in Israel

Turning silkworms into biomedical solutions

How did you come to work at the Weizmann Institute of Science?

I obtained my PhD in chemistry from Bar-Ilan University, focusing on the effect of mechanical fields — covering the entire sound energy range, including ultrasounds — on protein structure. I then moved to the University of Cambridge and studied the protein self- assembly phenomenon, which is associated with neurodegenerative disorders. I also cooperated with a group from Oxford University working on spider silk. We discovered that, in terms of supramolecular organization, certain types of silks are to some extent similar to those protein structures associated with Alzheimer’s and Parkinson’s.

Years later, when I got an offer to set up my lab at the Weizmann Institute of Science, I decided to focus most of my research on the material aspects of protein constructs. We’re harnessing all the knowledge and techniques I learned and developed during my studies to understand how we can control and possibly change the protein self-assembly path — and, in turn, how these changes may affect the functionality of protein constructs and biomaterial properties.

Could you give us examples of the work you do at the Shimanovich Research Group?

As I mentioned, we’re looking at the protein self-assembly phenomenon. For example, using silkworms, we’re imposing genetic modifications on silk proteins and letting them self- assemble. Our aim is to understand how these mutations change the self assembly pathway and whether they affect various biological functions, functionalities or properties — like mechanical characteristics, the rate of biodegradability and biocompatibility.

We’re not limited to materials that are made purely from proteins — we’re also looking at different types of natural building blocks. We’ve recently explored the capabilities of polysaccharides from food-industry waste; they have an excellent thermal responsivity that can be converted into electrical currents, but the problem with utilizing them is their mechanical instability. We discovered that if we combine a conductive polysaccharide with silk — known for its mechanical stability — we can construct a multifunctional material that’s mechanically strong, biodegradable and thermo-responsive.

What are some real-life implications of these experiments?

The ability to control protein self-assembly, especially the one that’s associated with material performance, opens up endless possibilities for the synthesis of materials with programmable multifunctional characteristics. For example, the technology developed in our lab allows us to create both highly stiff material and very extensible biomaterial, all assembled from the same building blocks: silk proteins.

The range of biomedical applications vary from controlling cellular growth and differentiation to tissue replacement, where programmable mechanical performance, biocompatibility and slow biodegradability are essential.

How does all this relate to the topic of sustainability?

We’re using materials that are either considered waste products or available in large quantities. Silk protein, for example, is cheap and known for its broad utilization in the textile industry. Our aim is to create technology that’s as green and as cost-effective as possible.

Do students get to contribute to this work?

I work with many different people — postdocs, a research associate, a consultant, PhD students, master’s students, rotational students, visitors from different countries. I collaborate with other professors that come either for a sabbatical from other universities or as part of the visiting professorship program. We also work closely with high school students. The lab is also part of a program that lets high school students spend about a month or two in the summer on a specific project of their choosing.

You’re also a teacher. How do you try to impart a love of physical and chemical materials to your students?

I teach a course in soft biomaterials and self-assembly at the Institute’s Feinberg Graduate School. The aim of the class is to provide students with knowledge about basic physical or chemical concepts related to the processing of natural building blocks, such as sugars, lipids and proteins. I try to identify and work with each student during the course; at Weizmann, class sizes are usually small, which means I get to work one-on-one and understand individual needs.

For their end-of-course presentation, I ask students to create a food dish or a cosmetic, either at home or in a lab, and then explain the physical and chemical processes involved in the task, such as heat transfer or emulsification and preservation of active ingredients. The idea is that when students perform something — even a small experiment — by themselves, they’re able to translate the knowledge they’ve acquired in class into practice, thinking about which processes are actually involved in a lab experiment.

A chemistry powerhouse

Ariel University is a great option for students who want to pursue chemistry or other STEM subjects. Why?

There’s real value placed on teaching and on the importance of personal connections with students. Their education is really taken seriously. I think, I hope, that students feel that. Professors are given the opportunity to interact with them, ask them what they want to focus on in their research and help them to develop those fabulous ideas.

We’re also providing opportunities for students to travel to conferences, present their work and interact with other researchers and faculty members. I had students who virtually presented at the American Chemical Society meeting in Atlanta, Georgia last August. Another student traveled to a workshop in the far north and is writing a paper based on the ideas he got during that weekend.

When it comes to the chemical sciences, the possibility to join a group and research whatever you’re interested in is open. Ariel just got a medical school; the university has a strong chemical engineering program; I work closely with the Wine Research Institute; and I’m developing a material sciences program. I think most international students who consider coming are by definition self-starting, ambitious and extremely independent. Ariel University is a really good place to be that kind of person.

You moved to Israel from the U.S. What advice would you give to students who feel nervous about moving to another country?

In the chemistry department, and I think in all the sciences, there’s a tremendous international population. When I was the age of our graduate students, the thought of moving abroad seemed incredibly daunting — a new culture, a different language. But what I see here is that international students form tremendous communities: they travel together, help new students settle in, form sports leagues and have cultural and social celebrations. It’s an enormous strength of the experience here.

Can you tell us about the work you do around wastewater purification?

Our aim is to figure out better methods of chemical detection. I can tell you what’s in my water because I’m a chemist with access to all the instruments that I need, but most people don’t have that capability. I want to develop technology for the general population that’s both as easy to use and cheap as possible, so that people can see if there are lead or other chemicals in their water and be able to make informed decisions about what they consume.

We know that there’s a correlation between exposure to certain compounds and developing some diseases, but we can’t really get a good handle on that mechanism – how it works and how to stop it – if we can’t accurately quantify a person’s exposure.

What would you say to encourage students to specialize in a chemistry subject?

Chemistry has a big image problem not just with students, but with the general population. As chemists, we have to do a much better job of explaining that what we’re doing is really important to make lives easier — and to save them.

There’s chemistry in everything. A lot of major advances in science that people see and use every day are based on chemistry, including Covid-19 antigen and PCR tests; vaccines, including the newly developed Covid-19 vaccines; pregnancy tests; and new sources for clean energy, including more fuel-efficient vehicles.

Men have a much greater representation in STEM subjects than women. What work are you doing to address this issue?

There’s still a significant disparity in the number of men and women who are active and successful in STEM fields. It’s critical to address this issue: the entirety of science benefits from a larger, more inclusive pool of talented individuals joining the field.

What we need to do at all stages, but especially around middle schools, is develop programs that tell girls, we know this is hard, but look how fun it is, what you could discover, how rewarding this can be. I’ve run a chemistry camp for middle school girls in the United States for seven years, and I’m thrilled to bring similar programs to Ariel University. The idea is to give girls positive experiences, strong role models, and to directly say, if this interests you, please continue. We’ll do everything we can to help you.

What advice would you give to students to make most of their time at Ariel?

Students should come into any institution with the expectations that they should ask for things, be self-starters, introduce themselves to more people — that’s how they’re going to get the most out of it.

When they ask me for advice about research, I tell them to think of anything in this world that makes them think: wouldn’t it be nice? Wouldn’t it be nice if my milk got spoiled without smelling? Wouldn’t it be nice if this food didn’t explode all over the cup when I try to heat it up? When I was a student, I was terrified people were going to fix all problems before I’d be able to get into research. It turns out there’s no shortage of problems to be solved.

Turning silkworms into biomedical solutions

Agriculture and the environment

Turning silkworms into biomedical solutions

A chemistry powerhouse

Promoting renewable energy

Sustainability taking center stage