Dr. Eyal Shimoni / 1964-2023
In Memoriam
Eyal became a member of the Electron Microscopy Unit at the Weizmann Institute in 2001, but for us it feels that he was there forever. Eyal was a good friend, a colleague, and the heart of the EM unit family. He was the one person who had deep knowledge in almost all methodologies at the EM unit from theory to practice. He was the one to teach, help, guide, and support with his amazing and unique spirit; with kindness, acceptance, and endless patience.
Eyal was a pioneer in the field of biological sample preparation, starting with his PhD studies in the Federal Institute of Technology, ETH, Zurich with Professor Hans Moor and Dr. Martin Müller (both pioneers in cryo-electron microscopy). Already during his postdoc in the group of Avi Minsky, Eyal knew that he wanted to be part of the EM unit.
Early after joining the EM unit, Eyal led the initiative for implementing Cryo-SEM, providing the ability to image high-pressure frozen, freeze-fractured samples. This was a completely new ball game for life science and added an essential capability (popular to this day).
Sample preparation was not the only field where he opened up new worlds of exploration. Eyal was also the one who recognized the need to go to 3D with thicker plastic sections and brought STEM tomography as a new method to our unit.
Using this technique, he made seminal contributions (in collaboration with the group of Ziv Reich) to understanding thylakoid architecture in plants. In many projects such as this one, he was not only a part of the technology development, but also played a major role in formulating the scientific questions and interpretation.
His contribution and his endless passion for developing new techniques played a crucial role in establishing the EM unit as a leading center for sample preservation cryo-SEM imaging and STEM tomography.
Eyal loved nature, and one of his hobbies was to observe it under the microscope. When you entered Eyal’s office you could not miss the aquarium full of water with creatures that he collected from the local Rehovot pond. The aquarium was his “baby”, and he nursed it enthusiastically. Every year he took a sample of water from the pond and followed the small creatures and life inside the aquarium.
We all miss him every day, both personally and professionally. We keep asking ourselves; what would Eyal say about this and that? How would he respond to this conflict? We are grateful and feel so blessed that he was and will forever be a part of our lives.
Prof. (Emeritus) Martin Kessel (Hebrew University of Jerusalem & National Cancer Institute, NIH) :
I first met Eyal soon after he came to the Weizmann in 2001. We immediately found a common bond thanks to the time Eyal spent in the lab of Martin Mueller and Hans Moor at the ETH in Zurich. I too had by that time many colleagues in Switzerland mainly through my interactions with the Eduard Kellenberger lab first in Geneva and then at the Biozentrum in Basel. Eyal and I knew many of these colleagues in common.
By the time Eyal came to the Weizmann I was already at the National Cancer Institute, NIH in the lab of Sriram Subramaniam. However, I was a regular visitor at Weizmann and we always met on those occasions to pursue our common interests in structural biology, EM instrumentation and specimen preparation. Once Eyal became active in the Israel Society of Microscopy, initially as the Secretary of the ISM in 2009, he and I enjoyed many hours discussing ISM affairs based on my previous experience as both Chairperson of the Society and as the Secretary.
Given our common interest in documenting aspects of the history of the ISM, one of the projects we established was the In Memoriam page on the ISM website. This page lists the Founders of the ISM and all subsequent members of the society who have passed away through the years. It was extremely sad to have to add Eyal’s name to the list with his passing last July.
In maintaining the list we both had to be sure that our facts were correct as to dates and where each person had worked in his career. Colleagues were invited to add personal reflections on the person. Whenever one of our colleagues passed away, Eyal’s compassion for the families was obvious. Fortunately these occurrences have been relatively few. This would always entail being in contact with the family and Eyal always a great comfort to them. The families very much appreciated the respect shown by the ISM to their family member which also included providing them an insight into into the colleague’s scientific work.
We would spend much time discussing a myriad of other ISM affairs. In 1991 the name of the Society changed from the Israel Society of Electron Microscopy to the Israel Society of Microscopy to reflect the growing importance of the new generation of high resolution light microscopes. Eyal was instrumental in the integration of the light microscopy community into the ISM. Eyal’s passion for bringing microscopy to students at schools led him to organize workshops and visits to microscopy labs for our younger generation. In particular, the SEM was his favorite tool in introducing the students to the wonders of the world of microscopy.
Eyal is sorely missed by all of us, especially those who worked closely with him in the EM Unit and all the “clients” whose projects came to fruition through Eyal’s dedication as a compassionate and skilled mentor and as a structural biologist.
Even now when I walk past what was Eyal’s office, I stop and and hear his welcoming voice – to come in and sit down and discuss whatever was important to the two of us…….
Every relationship Eyal had with others was special, because Eyal had this amazing ability to create a unique and special relationship with each and every person that he knew. And so too it was with me. Of course most of our interactions were about electron microscopy, but I want to describe an idea that Eyal had that may well prove to have a huge and lasting impact for generations. And it also gave me a lot more “Eyal time” that I now value even more.
Eyal kept this most unusual aquarium in his office – essentially an aquarium filled with mud and water from a winter pond near Rehovot. And of course including many of the organisms in this unique ecosystem. I shared his enthusiasm for this aquarium and somehow we got around to discussing an idea of his on how we could share such a world with others. This led to a broader discussion on sharing with others the wonderful experience of using a scanning electron microscope (SEM) to observe nature in its microscopic complexities, possibly including the winter pond world. Eyal told me that there were easy to operate desktop SEMs and suggested we put together a proposal along these lines. On the 29th March 2017 we submitted a proposal entitled:
Views Into Microscopic Worlds: Scale and Complexity and a Link to the World of Ongoing Research Proposal for Building Educational Modules Around a Special User Friendly Scanning Electron Microscope
The proposal was submitted to the vice president of the Weizmann Institute at the time Prof Michal Neeman. The proposal was accepted by the Weizmann administration, Eyal selected the specific SEM to purchase and together with Prof Ron Blonder and her PhD student Ella Yonai, the program was launched and was carried out by Ella and Ron. Close to a 1000 high school students have been exposed to this wondrous microscopic world through the SEM. The figure shows Eyal talking to a group of high school students during one of the meetings. This was Eyal’s idea and it was my privilege to do this with Eyal. I still cannot internalize the fact that just a few weeks ago, Ella submitted a paper for publication on the impact of this program and the paper is dedicated to the memory of Eyal, who had not even turned 60. How can this be? I don’t understand.
I do understand that it was not only the high school students, and their teachers and the world of science education that benefitted from Eyal’s idea, but I am one of the beneficiaries as well, because I had the chance to work with Eyal for 6 years on this project. I could learn from Eyal the wisdom of knowing when to be involved and when to keep a distance, I could have opportunities to get to know Eyal more than had we just worked together on research, and I almost had the opportunity to enjoy the satisfaction of sharing with Eyal the successes of this program. But only almost. Eyal was not able to attend the evening devoted to this program at the end of 4 years, or the ceremony in which Ella received a well deserved prize or contribute to the paper that was submitted. He was too weak.
We should add this special “Eyal initiated program” to the list of Eyal’s lifelong contributions. And I will say thank you to Eyal for asking me to help him initiate this program. He was a very very special person.
Prof. Paul Walther (Ulm University) :
Eyal Shimoni has made a number of outstanding contributions to the field of electron microscopy in the life sciences, particularly through his practical and theoretical work on sample preparation for electron microscopy using high pressure freezing techniques.
I met Eyal Shimoni for the first time at the ETH Zurich (Swiss Federal Institute of Technology) in 1993, when he started the work on his PhD thesis “Optimising Tissue Preparation for High Pressure Freezing: from Heat Transfer Analysis to a New Microbiopsy Device”. He did this work under the supervision of Hans Moor and Martin Müller, two important mentors of electron microscopy in Switzerland. Eyal first showed great skills in practical work when developing a microbiopsy device based on tiny gold tubes that need to be sharpened at one end. These tubes have been loaded into a pressurized air driven device, where a Teflon projectile accelerates the gold tube, so that it can penetrate into a piece of tissue. The gold tube with the tissue inside is then introduced into the high pressure freezing device and fast frozen at high pressure, thereby suppressing the growth of structure destroying ice crystals. The whole process is very fast and has been a real breakthrough since it allows for fixation of tissue pieces in a physiologically defined state without the formation of artifacts, that typically occur during the time-consuming process of cutting out a small piece of tissue with knifes and then mounting it on the high-pressure freezing holder. But Eyal did not only show practical skills during his PhD work, he also established computerized calculations about heat transfer during the process of high pressure freezing. He could show in silico that heat transfer is faster in specimen carriers of cylindrical shape (as realized in his microbiopsy device) than in the classical flat specimen holder. The resulting paper Shimoni and Müller (1998). “On optimizing high-pressure freezing: from heat transfer theory to a new microbiopsy device.” Journal of Microscopy 192, 236-247 is still considered as one of the most important standard works about high pressure freezing. This paper was a breakthrough and helped a lot to make high pressure freezing to become the “gold standard” preparation approach for electron microscopy in life science. I consider it as a privilege to have worked in the same lab during this time, giving us the chance for so many engaged and fruitful discussions in an excellent scientific mood.
I would like to mention two publications of Eyal that he wrote in the years after his PhD studies: the first is Shimoni E, Rav-Hon O, Ohad I, Brumfeld V, Reich Z. (2005) Three-dimensional organization of higher-plant chloroplast thylakoid membranes revealed by electron tomography. Plant Cell. 17, 2580-6. This paper is one of the early application of electron tomography to high-pressure frozen samples. The second one is Weiner A, Kapishnikov S, Shimoni E, Cordes S, Guttmann P, Schneider G, Elbaum M. Vitrification of thick samples for soft X-ray cryo-tomography by high pressure freezing. J Struct Biol. 2013; 181, 77-81. This paper now makes the next step and it shows that high-pressure freezing and Eyal’s former work is not limited to electron microscopy but can also be applied to new microscopical approaches, such as x-ray tomography.
More recently I have had the chance to discuss the concept of STEM (scanning transmission electron microscopic) tomography with Eyal, and since this discussion I really understand the method with which I have been working for quite some time already. It was always a wonderful privilege to discuss any topic with Eyal because he has been such an open-minded, human personality.
