Dr. John G. "Jack" Holt

Dr. John G. “Jack” Holt was born in 1929 in Buffalo, New York, the only child of two hard working parents. His birth mother Florence died when he was three, and his father Ernie, then remarried a wonderful woman, Mildred who loved him and raised him as her own. He grew up playing on the banks of the Erie Canal that his grandfather helped to build as a stone mason. Mildred was incredibly supportive of his early love of science and when he was 12, she bought him an old microscope from a retiring physician, introducing him to the world of microbes. Taking biology had to wait until college as his high school did not offer the course.

He attended Cornell University for his undergraduate studies and majored originally in Food Technology, which was state-funded and tuition-free at that time. He worked at various jobs while maintaining exceedingly high marks. At Cornell, he took an Introductory Bacteriology course, which awakened a lifelong passion for what he referred to as his “friends the microbes” and where he also first used Bergey’s Manual of Determinative Bacteriology, this ignited his ardent interest in classification and identification of bacteria. After graduating from Cornell in 1952, he went on to Syracuse University where he completed his M.S. degree in Microbiology. He then continued his graduate studies at Purdue University where he earned his Ph.D. in 1960. While at Purdue, he met Bess-Gene-Gillespie, also working on her Ph.D., and they were married in 1955.

Jack spent the rest of his career working and exceling in the field of microbiology and taxonomy, developing and serving as Editor-in-Chief of several editions of Bergey’s Manual of Determinative Bacteriology and Manual of Systematic Bacteriology. From a post-doctoral position at Iowa State University working under the editor and chairman of Bergey’s Manual Trust, to becoming a well-loved professor at ISU, taking over the role of editor and chairman of the Trust, to moving the Trust to Michigan State university in the late 1980s until his retirement in the mid 1990s. He was well known for his humorous lectures and his thoughtful advising of students.

Jack and Dr. Bess-Gene Holt were married for 36 years, until her death in 1992. Bess-Gene was a well-known specialist and author in the field of Child Development, and their marriage was a match of intellect. They held deep respect for each other’s knowledge and collaborated on Bess-Gene’s best-selling book; Science with Young Children. They had three beautiful daughters, all who survive him: Juliet Holt Klinger (Christian), Eva Holt Howard (Jonathan), and Susan Sass (Roger) along with their two children Paul Sass (Selene) and Hillary Sass. The years with Bess-Gene and the kids were some of his fondest memories, exposing the kids to camping, fly fishing, natural wonder, and travels to National Parks and Forests in the U.S. and Canada each summer. A strong feminist, he instilled a sense of curiosity and exploration in his girls, always believing in their abilities and skills.

Jack fully used both sides of his brain with aptitude not only in science but in art as well. He was an exceptional artist with a passion for carving wood and stone into sculptures and jewelry, an expert weaver, and a ceramicist.

In 1993 he married Dr. Lydia Kalinina, who preceded him in death in 2024, a well-known protozoologist and cryobiologist from St. Petersburg, Russia, who was a Visiting Scientist at the NSF-funded center for Microbial Ecology at Michigan State University. Once retired, Lydia and Jack moved to Venice Florida in 2001, where they enjoyed meeting new people, collecting art, traveling to Europe and Russia, and spending time on the beach combing for shells and stones. Jack loved his retirement as it gave him time to voraciously read, sculpt, and focus on political and world news.

Jack’s passion for science, art, and nature are a part of all his family. His incredible sense of humor and dry wit, his passion, knowledge, his rare kindness and compassion for others, and all that made him who he was, will be greatly missed.

In lieu of flowers, memorial donations may be made to www.support.tidewellfoundation.com