Hamilton Othanel Smith is a microbiologist from America who received the Nobel Prize for Physiology or Medicine in 1978. He shared the prize with two other microbiologists for the discovery of ‘restriction enzymes’ that could divide the DNA in a cell into smaller pieces so that its construction could be studied more easily. The other two microbiologists who shared the prize with him were Werner Arber from Switzerland and Daniel Nathans from America. The ‘restriction enzymes’ discovered by Smith was a new type of enzyme that could recognize a certain sequence of nucleotides in a DNA or ‘deoxyribonucleic acid’ molecule and could cut the molecule at that very point. This discovery laid the foundation for using ‘restriction enzymes’ as a tool in genetics and microbiology for studying the DNA of different kinds of biological systems in later experiments.
In 1970, Hamilton Smith published his first book ‘A restriction enzyme from Hemophilus Influenza. 1. Purification and general projects’ in collaboration with Kent W. Wilcox.
His second book ‘A restriction enzyme from Hemophilus influenza. 11. Base sequence of the recognition site’ in collaboration with T. J. Kelly was published in 1970.
His third and fourth books in collaboration with P. H. Roy titled ‘The DNA methylases of Hemophilus influenza Rd. 1. Purification and properties’, and ‘The DNA methylases of Hemophilus influenzae Rd. 11, Partial recognition site base sequences’, were published in 1973.
Hamilton Smith received the Nobel Prize in Physiology or Medicine in 1978.