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Dr. Nancy Ho


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Dr. Nancy Ho, a problem solver and a person with vision.

Dr. Ho’s childhood was marked by numerous illnesses, which made her feel inferior to other children of her same age.  She felt herself to be a “worthless” child and a burden to her family. This seeded her strong desire to accomplish something worthwhile in her life and contribute to society if given the chance.

After Dr. Ho completed her Ph.D. at Purdue University, she stayed at Purdue for personal reasons.  She always thrived on solving important problems in science and technology.  Two years after she received her Ph.D. from Purdue, she began to intensely study the development of a new method for fragmenting the structure of DNA – facilitating the analysis of its sequence.  Back then DNA was still a “black box” in molecular biology, with no suitable means to delineate its intricate structure. Her grant proposal for that project (the very first formal proposal she ever submitted) received great reviews from the three agencies the proposal was submitted to – NIH, NSF, and the National Cancer Institute.  They all awarded her grants.  From that time on, she supported herself as well as the scientists working with her at Purdue University.

As a scientist, Dr. Ho’s greatest strength has been her ability to critique her own work and appreciate other scientists’ talent and innovation.  After several years of hard work, the method that she was developing for determining DNA structure was proceeding well.  However, novel restriction enzymes were discovered by then.  She foresaw that restriction enzymes were far superior for tackling the DNA structure.  As such, she gave up her own pursuit and vigorously studied these novel restriction enzyme-based recombinant DNA techniques.  Within a year or so, she became a specialist in recombinant DNA technology at Purdue.  When Purdue’s Laboratory of Renewable Resources Engineering (LORRE) needed such an individual to help them shape their strategy for developing a recombinant microorganism to ferment xylose from biomass, she was recommended to Dr. George Tsao, the Director of LORRE.  Once Dr. Tsao contacted her, she was intrigued by the project because it was an ideal case where the application of recombinant DNA technology could make a real difference.  Furthermore, if successful, she believed that such engineered yeast could help to solve the world’s energy and economic problems in the future.  She decided to join LORRE to lead the study.

In the early 1980s, there were about ten groups independently pursuing the task of genetically engineering the Saccharomyces yeast to ferment xylose and more than half of the groups were in the US.  Both the USDA (The United States Department of Agriculture) and the DOE (the Department of Energy) National Laboratories had at least one group pursuing this goal as well.  Not only was her group the smallest, but Dr. Ho also had to obtain most of her own funding – through grant applications to the Federal Government Agencies – to support her group’s research.

As mentioned under other sections of this website, Dr. Ho’s Group at Purdue was the first group in the world succeeded in the development of the genetically engineered yeast that could effectively co-ferment both glucose and xylose to ethanol in the world.  Dr. Ho received numerous recognitions for her efforts in the development of the recombinant yeast for co-fermenting glucose and xylose.  Some of them have been included in this website.

Dr Ho was able to design and develop this ideal yeast for cellulosic ethanol production not only because she was a dedicated and serious scientist, but more so because she is a problem-solver and a person with vision.  When she decided to participate in the genetic modification of the yeast, she had never done any formal research on yeast and knew little about yeast scientifically. However, she had a strong belief in human ingenuity. She believed most problems could be solved given enough effort and time.

Dr. Ho designed her yeast using basic scientific principles, logic, and a fair bit of imagination. Each step and approach was revisited countless times.  Her hard work paid off, and eventually culminated in the development of her breakthrough technology.

Since 1993 to the present, her group has continued to improve the Saccharomyces yeast to more cost effectively produce cellulosic ethanol on an industrial scale.

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