John Howard Northrop

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John Howard Northrop

John Howard Northrop (July 5, 1891 – May 27, 1987) was an American biochemist and Nobel laureate whose work in isolating and crystallizing enzymes, which are proteins that catalyze biochemical reactions, significantly advanced the understanding of their structure and function. His research laid the groundwork for the later development of protein X-ray crystallography, an essential tool for elucidating the molecular structures of biological macromolecules.

Early Life and Education

John Howard Northrop was born in Yonkers, New York, to John Isaiah Northrop, a zoologist and instructor at Columbia University, and Alice Rich Northrop, a teacher and botanist. Inspired by his parents, Northrop developed an early interest in science, particularly in biology and chemistry. He pursued his undergraduate degree at Columbia University, where he also completed his Ph.D. in chemistry in 1915. His doctoral research focused on the enzyme invertase and its role in catalyzing the hydrolysis of sucrose.

Career and Research

After completing his Ph.D., Northrop continued his research at the Rockefeller Institute for Medical Research (now Rockefeller University), where he would spend the majority of his career. His early work involved studying the digestive enzymes pepsin, trypsin, and chymotrypsin, which he successfully crystallized, demonstrating that enzymes are proteins. This was a significant breakthrough at the time, as it challenged the prevailing belief that enzymes were non-proteinaceous in nature.

Northrop's method of isolating and crystallizing enzymes allowed for the precise study of their biochemical properties and mechanisms of action. His work provided strong evidence supporting the enzyme theory of life, which posits that biochemical processes are catalyzed by specific enzymes. In 1938, he isolated and crystallized the first bacteriophage, a virus that infects bacteria, further demonstrating the protein nature of viruses and contributing to the field of virology.

Nobel Prize

In 1946, John Howard Northrop, along with James B. Sumner and Wendell M. Stanley, was awarded the Nobel Prize in Chemistry "for their preparation of enzymes and virus proteins in a pure form." This recognition underscored the importance of their contributions to biochemistry and molecular biology, particularly in understanding the chemical nature of enzymes and viruses.

Legacy and Impact

Northrop's work had a profound impact on the field of biochemistry and molecular biology. By demonstrating that enzymes are proteins, he paved the way for future research into the structure and function of enzymes and other proteins. His techniques for isolating and crystallizing enzymes are still used today, with modifications, in biochemical research and biotechnology.

Northrop's contributions extended beyond his research findings. He was a mentor to several future scientists and was known for his dedication to scientific inquiry and education. His legacy is reflected in the continued study and application of enzymes in various fields, including medicine, where enzyme-based treatments and diagnostics have become increasingly important.

Personal Life

John Howard Northrop was married to Louise Walker, with whom he had two children. He was known for his modesty and dedication to his work, often avoiding the spotlight despite his significant achievements.

Death and Honors

Northrop passed away on May 27, 1987, in Wickenburg, Arizona. Throughout his life, he received numerous awards and honors in addition to the Nobel Prize, including election to the National Academy of Sciences and the American Philosophical Society. His work continues to be celebrated for its groundbreaking contributions to science.