HindII
Encyclopedia
H.O. Smith
, K.W. Wilcox, and T.J. Kelley, working at Johns Hopkins University
in 1968, isolated and characterized the first restriction nuclease whose functioning depended on a specific DNA
nucleotide sequence. Working with Haemophilus influenzae
bacteria, this group isolated an enzyme
, called HindII, that always cut DNA molecules at a particular point within a specific sequence of six base pairs. This sequence is:
They found that the HindII enzyme always cuts directly in the center of this sequence. Wherever this particular sequence of six base pairs occurs unmodified in a DNA molecule, HindII will cleave both DNA backbones between the 3rd and 4th base pairs of the sequence. Moreover, HindII will only cleave a DNA molecule at this particular site. For this reason, this specific base sequence is known as the "recognition sequence" for HindII.
Hamilton O. Smith
Hamilton Othanel Smith is an American microbiologist and Nobel laureate.Smith was born on August 23, 1931, and graduated from University Laboratory High School of Urbana, Illinois. He attended the University of Illinois at Urbana-Champaign, but in 1950 transferred to the University of California,...
, K.W. Wilcox, and T.J. Kelley, working at Johns Hopkins University
Johns Hopkins University
The Johns Hopkins University, commonly referred to as Johns Hopkins, JHU, or simply Hopkins, is a private research university based in Baltimore, Maryland, United States...
in 1968, isolated and characterized the first restriction nuclease whose functioning depended on a specific DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
nucleotide sequence. Working with Haemophilus influenzae
Haemophilus influenzae
Haemophilus influenzae, formerly called Pfeiffer's bacillus or Bacillus influenzae, Gram-negative, rod-shaped bacterium first described in 1892 by Richard Pfeiffer during an influenza pandemic. A member of the Pasteurellaceae family, it is generally aerobic, but can grow as a facultative anaerobe. H...
bacteria, this group isolated an enzyme
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
, called HindII, that always cut DNA molecules at a particular point within a specific sequence of six base pairs. This sequence is:
- 5' G T ( pyrimidine: T or C) ( purine: A or G) A C 3'
- P3' C A ( purine: A or G) ( pyrimidine: T or C) T G 5'
They found that the HindII enzyme always cuts directly in the center of this sequence. Wherever this particular sequence of six base pairs occurs unmodified in a DNA molecule, HindII will cleave both DNA backbones between the 3rd and 4th base pairs of the sequence. Moreover, HindII will only cleave a DNA molecule at this particular site. For this reason, this specific base sequence is known as the "recognition sequence" for HindII.