Located near the center of the US population, Northwest Arkansas is, quite simply, in the middle of everywhere. There are several Midwestern markets within a half-day's drive, including Kansas City, St. Louis, Dallas-Fort Worth, Little Rock, Tulsa, and Oklahoma City.
Restriction enzyme. A restriction enzyme or restriction endonuclease is an enzyme that cuts DNA at or near specific recognition nucleotide sequences known as restriction sites.
The efficiency with which a restriction enzyme cuts its recognition sequence at different locations in a piece of DNA can vary 10 to 50-fold. This is apparently due to influences of sequences bordering the recognition site, which perhaps can either enhance or inhibit enzyme binding or activity. A related situation is seen when restriction recognition sites are located at or very close to the ends of linear fragments of DNA.