John Tymoczko

27 May 2019
John Tymoczko

John Tymoczko, age 70, died May 26th of a heart attack. John taught Biochemistry and Molecular Biology at Carleton for 39 years, beginning in 1976 as an Assistant Professor of Biology and retiring in 2015 as the Towsley Professor of Biology, Emeritus.  

John was a popular teacher, known for his “wacky and irreverent” sense of humor that was often woven into his lectures. He taught courses that included Energetics and Genetics, Exercise Physiology and Biochemistry, and Oncogenes and the Molecular Biology of Cancer. His gentle yet razor sharp wit was able to calm any tense situation and he refused to take himself too seriously. He was a generous colleague and a wonderful mentor to young faculty and students. John’s genius as an educator also touched many thousands of students far beyond Carleton as he co-authored the world’s leading upper-level Biochemistry textbook.  

John was also a fanatical exerciser and could often be found at the Rec Center or out on his bicycle. His infectious laugh will be missed by so many.

A celebration of John’s life will be held Saturday, June 1st, at 2pm in Great Hall. A reception will follow, also in Great Hall.

Gifts in memory of John may be given to the John Tymoczko Scholarship Fund, c/o the Development Office, 200 Division Street, Northfield.

View John’s obituary on the StarTribune website.

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  • 2019-05-27 16:18:54
    Leon Lunder

    John was incredible teacher, colleague and friend. He both experienced, and shared, the joy of learning and life. He was brilliant but never lost his curiosity. His enthusiasm was contagious as he went full out in everything he did. I was privileged to teach with him and looked forward to our conversations concerning the science of exercise. Each of us is unique, and John was incredibly special. My thoughts are with Alison and their family. We are all better for having had John in our lives.

  • 2019-05-28 16:24:19
    Jacquelynn Goessling

    I remember being shocked when in Bio for the Humanist we had, after three weeks of 'Life Cycle of the Pond' and 'Homing Instincts in Birds and Bats', John's three weeks of Recombinant DNA. He gave me the only F of my life on the final. I also remember inviting Alison, with whom my sibling and I had camped for years, and John along on a camping trip and him responding, "Why would I camp? I don't even sleep with the window open." I remember him for so much more, though. His humor, his interest in people, his crooked grin, his delight in becoming a grandfather, and his wonderful partnership with Alison. The world is a poorer place without John.

  • 2019-05-29 08:25:26
    Wendy Urban-Mead

    John was my professor for Bio for the Humanist ever so many years ago when I was a Carleton student. I greatly enjoyed the class, and in retrospect I feel sad that my internalization of the humanities-stem divide made it hard for me to have confidence to take more biology. But mainly, John became my dear friend Alison's husband. Their wedding was a joyful occasion in which I was so thankful to participate. My too-rare visits to Northfield in the years since then were always richer due to John's exceptional, keen attention and delightful wit. Admired, enjoyed, appreciated. John's death is a life-changing loss for Alison and Nick and Janina and the rest of the family. My condolences and love to each.

  • 2019-05-29 09:29:59
    Marcia (Cowen) Geyer

    John was a classmate of my brothers. Deepest sympathy to all of John's family and friends. John was one of Arnold's best.

  • 2019-05-29 09:49:07
    Linda Mueller

    I remember meeting John for the first time when he volunteered to attend the Accepted Student Days Welcome Dinner. His smile and enthusiasm was contagious! I quickly learned that I could always count on John to help out with the events hosted by Admissions. My condolences to his family.

  • 2019-05-29 12:34:33
    Jeremy Berg

    John was my co-author for 5 editions of our Biochemistry book and wrote 3 editions of a smaller Biochemistry text for a 1 semester course. Over two decades, John was an outstanding colleague---a thoughtful scholar and a very hard worker, always ready with a bad pun to lighten a discussion. He clearly cared deeply for his students and other readers of the book and worked on creative ways to make the material accessible and interesting without losing accuracy or rigor. He will be missed. Best wishes to Alison and the rest of his family.

  • 2019-05-29 17:11:07
    Ben Stiegler '77

    John showed up in '76 when I was a junior bio major. Though I never had any classes with him, I loved his energy, humor, irreverence, and ways of making you think about things. Decades later, walking with my then-prospect daughter thru the bio department, I stopped her to point out something wacko that he had drawn and posted, saying "isn't this the sort of place you would fit in?". Today she's a junior linguistics/classics major, and I like to think John's little cartoon had a positive effect on her, too. RIP John - may your memory be a blessing to all your students, friends, and family.

  • 2019-05-29 17:11:21
    Angel Solis

    I took four classes with John, and my only regret is not taking more. John is a fantastic teacher, and the reason I decided to study biology. He always treated me and all his students with tremendous respect. His textbook is a staple in any biologist's library, and I find it everywhere I go. John will not be forgotten.

  • 2019-05-29 17:20:20
    Mouni Audeh '77

    John was a new teacher at Carleton as I was finishing my last years as a Biology Major, and he was a great and enthusiastic teacher who opened my eyes to the then emerging world of molecular cancer biology. He had a major influence on me, and my interests, as I went on to study Genetics and Medicine and ultimately Oncology. I made a point of seeking him out with every reunion visit to Carleton, to try to express the impossible, which was to let him know what a huge and positive effect he had had on me. I know all the many students who were his pupils after that first year of 1976 must have benefitted greatly from his efforts, as I did. We will miss you, John. And thank you...

  • 2019-05-29 18:12:56
    Ann Isaksen

    "If you are ever worried about screwing up something, just think of me. I've screwed up almost everything at least once and it still turned out OK, so you will be fine." As a stressed out student who still felt like one wrong move or bad grade would ruin the course of my life forever, this random quip in the middle of a lecture resonated so strongly with me, that i still think of it 20y later. Thank you Dr Tymoczko for your humor and humility.

  • 2019-05-29 18:17:52
    Aaron Poley '95

    John was my favorite teacher at Carleton, among many greats. He had a fantastic sense of humor. The joke I remember best is him ending many complicated explanations of biological phenomena with the line, "But, what it really means is that it's all about relationships." What I liked about him best was that he made it very clear that he liked me, and that's so important in education even at the college level. He will be missed by me and many. He, Alison and the whole family are in my thoughts and prayers.

  • 2019-05-29 18:20:25
    Michael Estrera '01

    John and Alison were one of the first people to welcome me to Carleton back in in the summer of 1997 when I attended a pre-frosh math and science program. I remember spending a wonderful summer taking a biology class with Jon as well spending time at their home. Thank You!

  • 2019-05-29 20:51:17
    Chris Bystroff '83

    John sparked my lifelong love for biochemistry. I will forever remember the weirdness and excitement of his lectures. He often carried on two dialogs at once, sometimes three -- the first voice was actually the lecture, the second voice interjecting comments about the lecture, and sometimes a third voice, that was a sort of out-of-body spectator voice, commented on the amazing brain of John Tymoczko. Now I lecture like John.

  • 2019-05-29 20:56:02
    Elise DeVore Berlan

    John was one of my favorite profs at Carleton, and influenced me greatly. He held biology seminars in his home, and they were formative for me. I loved how included I felt and how informal he was. He inspired in me a love of teaching and working with young people that I has remained with me over the years and, in part, led to my career choice as an Adolescent Medicine academic physician. He will be greatly missed by many. Alison, my thoughts are with you and your family.

  • 2019-05-29 21:42:31
    Mary Schroth '82

    Thank you John for your love of biochemistry, teaching undergrads and natural curiosity. Your sharp wit and grounded approach to life was reassuring to overwhelmed undergrads. You left a legacy and will be greatly missed. My thoughts and good wishes are with your family.

  • 2019-05-29 22:37:07
    Allison Kirschenmann '88

    I was a bio major who never had John as a prof but we rubbed shoulders for a couple years when I worked down the hall from him in Rich Wong's lab. In 2005 he invited me to give a talk to the students about opportunities in industry and the controversy at the time of pain relievers and heart attack risk. Despite the fact I was working for a company that sold pain relievers, the talk reflected my professional opinion that most, if not all pain relievers carried an increased risk and should be used with caution. True to his mischievous nature and maybe a drive to balance the message to the students he asked what was probably the only question after my talk: "Aren't pain relievers good for when your knees hurt and you really want to put some miles on your bike?" I didn't have good answer for him then and thought of John every time I popped one for a headache. Thank you John for challenging me with an existential question when I least expected it.

  • 2019-05-30 00:46:48
    Sarah Hamm-Alvarez '86

    John provided me with my first actual research experience as a summer research intern in 1984 in his laboratory when I was a sophomore at Carleton. I required a lot of training and patience but this was a great and formative experience and introduced me to the wonders of biochemistry and research. I subsequently have pursued a career in academia and scientific research and it all started with that summer in the laboratory! My thoughts and best wishes are with your family and I thank you for the experience and patience.

  • 2019-05-30 08:45:44
    Ravi Uppaluri '87

    As with many others here, John had a profound impact on my life/career and I am proud to have been part of his legacy. During a period in my sophomore/junior years where, clearly in retrospect, I was pretty lost, he took me on in his lab, helped foster my scientific curiosity, guided me for my senior honors comp., hired me to work in his lab after graduation, helped me get into medical school and directed me to the lab in which I ultimately also got my PhD. In short, he believed in me. Outside of the lab, the time spent with Allison, John and some of the other lab members introduced me to his wide ranging interests and quirky sense of humor. I treasured his mentorship and friendship and owe my career to him. My thoughts are with Allison and his family. May he rest in peace.

  • 2019-05-30 16:54:56
    Ingrid Sparrow '84

    As a biology major I was fortunate to have many talented and inspiring Biology Professors, but none that made me laugh in class as much as John.  I took his Biochemistry class in the spring (aka Baseball Season) when he trialed teaching the Kreb Cycle as a nine inning baseball game.  He was correct in that the analogy was not perfect.  But  it was memorable!  With my work studies being in the Bio Stock Room or as the Building Monitor, our paths crossed at odd times of days and places, and John was  always ready to listen to or tell a story, with a grin ready to expand. His most incredulous grin being when my lab partner, and his future wife Alison, were working on color chromatography late one night.  On our way to pin our results to his door, we inexplicably collapsed in giggles in the stairwell going to his office.  His tousled hair peering down the stairwell only made us laugh harder.  But I think we passed the lab anyway. His love of science, teaching and people was sincere and joyous, and will be deeply missed.  He and his family are in my thoughts.

  • 2019-05-31 05:16:33
    Katie Sawai '02

    "Laisser les bon temps rouler." If I'm not mistaken, this was on the Intro to Biology 123 syllabus that John handed out on the first day of class way back in winter 1999. John had a way of capturing your attention and presenting complicated processes in a way that anyone could understand. Biology was something that sparked joy for him and is something that he passed on to others including me. I was fortunate enough to have John as both a teacher and advisor. Beyond his love for science was a kind and compassionate human who deeply cared about his students and went to great lengths to help them, as he did for me when I was scrambling to figure out what to do after graduation. John, thank you for everything. If not for your guidance, I would not be where I am today. You are missed. To Alison and his family, my thoughts are with you.

  • 2019-05-31 10:36:22
    DeeDee Rupert

    Dear John, Thank you for being a wonderful professor, mentor, and friend to so many Carleton College students like myself. Thank you for being the kind of teacher that, when faced with educating pre-medical students, did not balk at their over-eager or mock their over-ambition, but instead connected with them on a personal level- reminding them of the wholeness of life, the simple pleasure of a good meal among friends or a walk outside. You accepted students for who they were and brought out the best in them. I will cherish our office hour conversations; your patience, passion for biochemistry, and most of all humor and wit. In my senior year I brought you my copy of your textbook to sign. I remember you were very surprised and laughed heartily, telling me: “you know this is going to be worth about $5 next year.” I wanted that signed copy because to me you were an amazing success, an inspiration; someone who had “made it” in the sciences, “made it” as an author, and did not let the hardships of that career path harden you but remained ever humble and ever kind. That textbook will remain on my shelves and grace my offices as I make my own journey through graduate and medical school (I am currently in an MD-PhD program). Thank you for touching the lives of so many students like myself. You will be missed. You are remembered. With respect and appreciation, DeeDee Rupert ('11)

  • 2019-05-31 11:43:43
    Bob Mackin '82

    A mentor, a colleague and a friend. From the time I first heard you in Bio 10, through Biochemistry, working in your lab and the special comps project with the Chemistry Department that you helped facilitate. Dinners at national meetings, an invitation to give a seminar and bumping into you (usually by accident) on numerous occasions while I was in Northfield to visit my children at Carleton. You stimulated a live-long passion for biochemistry and modeled a joy for life and career. Thank you for being the person you were.

  • 2019-05-31 20:20:10
    Kathy Lee '86

    I had the pleasure to work in John's lab my senior year for Honors Comps.  I was so flattered that he asked me to work with him.  He also arranged for me to spend a summer at Washington University doing research.  In these two moves, he launched my medical career.  Alison was his lab tech my senior year, having just graduated.  I remember their warm friendship but at the time had no clue about its serious nature and where it was headed!

    I enjoyed John's crazy sense of humor and also that he did not take himself too seriously.  He and Ali were an awesome pair. My heart is with Ali and John's family.

    My children attend Carleton and St. Olaf, so we have spent a bit of time in Northfield recently.  I think I spotted John on his bike a few years ago.


  • 2019-06-01 08:35:49
    Sabrice Guerrier

    I got the opportunity to know John while teaching at Carleton from 2011-2013. I was nervous, as this was my first teaching experience. And my nervousness was heightened by the thought of teaching with John whose textbook I had used as an undergraduate and graduate student. John's incredible humor did much to make me more comfortable in the classroom, but there was one particular experience where John took the time to empower me, the young and nervous professor. John was teaching the lecture portion of Biology 126, while I taught one of the lab sections. I attended all his lectures sitting in the back of the large lecture hall. Hearing John lecture would make any young professor reconsider his/her choice to teach since his command of the room and the subject matter seemed like an unreachable goal. So one can imagine my surprise when John was asked a question by a student then responded that he did not know. Instead John pointed to me and said that "I bet Sabrice knows the answer. He is an expert in this area." John could have conceived an answer to any question that would have arisen in that class, but rather than answer he sought an opportunity to treat me as a colleague even though I had not yet considered myself to be his.

  • 2019-06-01 18:08:49
    Jim Lee ‘85

    John had a tremendous impact at Carleton. He was a great teacher, but he stood out because he was such a great person. His mentorship, intellectual curiosity, sense of humor, and kindness helped many of us in our career paths and lives. I will be forever grateful for his guidance and support. Deepest condolences to Alison, John’s family, and to all of his friends. John will be missed.

  • 2019-06-02 03:53:28
    Stephanie Sampson Watowich '83

    John was a life long mentor, teacher, and friend, and he will be greatly missed. At our last visit over coffee at Goodbye Blue Monday in Northfield in September 2017, John shared his excitement over his grandchildren and his life in Mexico and Northfield with Alison. John paved the way for me to pursue a career in academia, and I will always be grateful to him for this as it has been most rewarding. Although I did not realize until much later, John's mentorship was essential, particularly for a woman entering the scientific research field in the early 1980s. John supported, coached, and guided my pursuit of research, all without bias or discouragement based on gender. This was extremely fortunate as when I encountered these issues later, I already had the strength and resolve to stay on course. Importantly, John was also a firm believer in the liberal arts, allowing me to go on an art history off-campus program in Greece during my senior year, when I should have been taking his required Biochemistry course. I'm not quite sure my substitute Biochemistry course was sufficient, but certainly the time in Greece was incredible! Thank you, John, for your deep wisdom and caring. You'll continue to inspire me as a scientist and mentor to others.

  • 2019-06-02 09:40:39
    Ken Poss '92

    When I think of Carleton, I think of meeting my future wife, a tight circle of friends, and John Tymoczko. As a junior, I enrolled in John’s Biochemistry class, and then his Cell Physiology class (a class size of 3!). I absorbed the material and loved the teaching style – rapid fire with humor woven in. John invited me to do an independent study in his lab - I took the bait and was hooked. I found my calling, and I’ve been doing experiments in or directing a large academic research lab ever since. I have lots of fond memories from the year and a half working with John – doing PCR side-by-side using water baths; talking science and science politics; taking light jabs and wondering how to give back; dinners at John’s house with Alison and other students on steamy Northfield nights; preparing for my first scientific conference; and talking graduate school and careers. Really important is that, in the summer of ’91, John would go on long bike rides every day, with goals of ambitious mileage and time to think, leaving me on my own in the lab much or most of the time. He’d say ‘you know how to do this, you got this’. I can’t imagine a better career prep or mentoring style for me to develop independence, confidence. John introduced me to scientific research and it was an honor to be mentored by him.

  • 2019-06-02 11:47:29
    Becca Greenstein

    I took Bio 126 with John as a sophomore and prefected for the same course the following year. I asked him to write me a recommendation letter for a summer research position between junior and senior years. When he asked for more details about my research position the previous summer, I told him it hadn't gone so well because of unrealistic demands from my PI. He said, "Okay" and walked back in his office to finish the letter. I ended up with a great summer research experience that summer, thanks in no small part to his unwavering belief in me as a scientist.

  • 2019-06-02 16:58:28
    Stephanie Smythe "77

    John arrived at Carleton in time for my senior year. I took biochem, followed by cell physiology, followed by an independent study, and then spent the summer as an NSF fellow in his lab. Then I went to the University of Chicago where I spent 2 years working for his mentor and PhD advisor, Shutsung Liao. What did I learn? Molecular biology is fascinating stuff. My earlier assumption that I wanted to work directly with people was correct. MD, not PhD, for me. Humor is important. Whatsammater U anyone? So is hard work. Go for it. Take things seriously, whatever you do, and there's no need to be somber about it. Care about people as much as the science. Thanks John, you are already missed.

  • 2019-06-03 14:56:56
    Laura Pogemiller Caron

    I remember thinking "I get Intro to animals and intro to plants...but what is this Intro energy?" I think only John could make that intro material so engaging- and do it over and over.  He really got a kick out of watching the lightbulb click every time a new class understood.  It was such an honor to have him ask to me to a TA- to think he'd noticed me- but he really saw people.  I remember setting up a Biochem lab asking if I should do prep under the hood.  He gave me a huge grin and told me not to worry if my lungs stung a bit when I was preparing solution A-  it is just really lipophilic so it will dissolve your cell membranes for a bit. In my senior year, after a summer of being biostockroom staff with Alison and having John as my thesis advisor I invited them for dinner.  I was shocked they said yes but they came and sat in our little off campus apartment and made conversation with me like a real grown up.  They even ate the one meal I knew how to cook.  You were both a big piece of my Carleton life.  Thanks John and Alison

  • 2019-06-03 15:37:26
    Joe Rosen '85

    I didn't know it at the time but hormone receptors (my Senior Comps topic) and oncogenes would eventually become my life. John was a fun person and exceptional teacher---something I didn't really realize until post Carleton life. I'll always remember John's lecture comparing the steps in the Krebs Cycle to the innings of a baseball game. Its true, baseball really is a metaphor for life. My condolences to Alison and her family. I'm so sorry for your loss.

  • 2019-06-13 13:56:57
    Sean Beckwith '12

    I took John's Biochemistry course in 2010 and still hold dear the phrase he would put on his exams: "Endeavor to persevere". He was a great teacher in a challenging class and a quirky and indispensable professor in my biology major experience. After Carleton, I completed a biology PhD and now am a researcher in a biochemistry department and am delighted to see the impact he has had and continues to have through his textbook in the training of my colleagues and students. John is an inspiration to his students and I hope to carry his spirit in my career.

  • 2019-07-30 15:24:02
    John Stebbins '88

    I was stunned and deeply saddened by the news of John's passing. John was a towering figure in my life; I cannot fathom the track it would have taken without his guidance, influence, and support. I remain profoundly grateful for all that he did for me. My most sincere condolences to Alison and the family.