Wednesday, February 15, 2012
Louis Pasteur and his Contributions to Early Biotechnology
My interest in microbiology, the fundamental field of biotechnology was ignited when I took the General Microbiology course as a biology undergraduate with Dr. Hullett at the University of Illinois. Her love of teaching and her interest in microbiology were apparent and infectious. She was the perfect role model for impressionable undergraduates. It was after taking her course that knew I would go on to earn the doctoral degree in microbiology and to make a career in academia. In addition to Dr. Hullett, there were two other mentors with whom I had the distinct privilege of working under during the course of my educational career. They were my master's and doctoral degree mentors respectively: the late Dr. Gerald Seaman, a renowned biochemist whose research was focused on microbial metabolism and the late Dr. James Jay, a bacteriologist whose research focused on food microbiology.
All three held Louis Pasteur in the highest regard as one of the key scientists who made the greatest contributions to the development of the biotechnology field. Dr. Jay had a poster in his lab of a Pasteur quote in French which translates to: "The microbes will have the last word". The poster was often a source of extensive discussion and debate in the lab among Dr. Jay's students and in the end we all agreed with Pasteur. I too came to have great respect and appreciation for Louis Pasteur's immense contributions to the field. There is no doubt that the microorganisms will indeed have the last word after all other organisms are dead and gone. Microbes clean-up wastes and recycle elements. Pasteur is the Father of Food Microbiology as Gregor Mendel is indisputably the Father of Genetics.
Louis Pasteur was trained as a chemist but made the most lasting contributions to the field of biotechnology. In 1857 he showed that the souring of milk was caused by microorganisms. He began his studies of wines in 1854 and determined that microorganisms were also responsible for the spoilage of wine. He then introduced the process of heat-treating wine with high temperature over time to kill undesirable microbes in wine. This process preserved and extended the shelf-life of wine and other beverages and became known as pasteurization. He published his findings on wine in 1866. Pasteurization provided huge economic benefits to the French wine and dairy industries. The process of pasteurization has been modified over time but is still in use today to preserve a variety of foods, notably milk, juices, beer, wine and many other foods.
Pasteur also conducted experiments that supported the Cell Theory and debunked the idea of spontaneous generation of microorganism. In 1860, he conducted controlled experiments using the famous swan-necked and straight-necked flasks in which he placed sterilized meat extract broths. He found that broth in the straight-necked flask became contaminated from exposure to airborne microbes while broth in the swan-neck flask remained free of contamination because airborne microbes became trapped in the curve of the swan neck flask and did not reach the broth. Pasteur's work was extended by scientists who came after him.
It is noteworthy that before Pasteur, a Frenchman named Francois Nicholas Appert made great strides in food preservation. Appert was not a scientist but a Parisian confectioner. In 1795, the French government offered a prize of 12,000 francs for the discovery of a practical method of food preservation. The French army was engaged in wars far from home and needed to have a safe way to store and transport food to support the army. In 1809 Appert was able to preserve meats in glass bottles that had been kept in boiling water for varying periods of time. Appert's discovery of preservation of meats was made public in 1810 and he was issued a patent for the process. This discovery led to food preservation by canning which ushered in several other milestones in food technology.
Early biotechnology was largely focused on food and agricultural technology: crop science, animal breeding and husbandry, food production, food spoilage, food fermentations, food processing, and food preservation. In the early to mid-20th century, industrial fermentations dominated the field of biotechnology and give us all sorts of important chemicals, enzymes, pharmaceuticals and other substances. In recent times, recombinant DNA technology is fueling biotechnology enabling the numerous advances in medicine around the diagnosis, prevention, treatment, and cure of human diseases; improved agricultural yields; improved livestock and animal husbandry; wild-life protection; and environmental protection and preservation.
Biotechnology is a multidisciplinary field that is in constant need of trained scientists in areas such as biochemistry, microbiology, genetics, cell and molecular biology, physiology, engineering, computer science and the emerging areas of computational science and informatics. The need to train students in the science, technology, engineering, and mathematics (STEM) fields has never been greater. Colleges and universities must do more to train and graduate STEM majors.