Restriction enzymes: commercial source

 Minotech Biotechnology
 Fermentas AB
 SibEnzyme Ltd.
 Nippon Gene Co., Ltd.
 Takara Shuzo Co. Ltd.
 Roche Applied Science
 New England Biolabs
 Toyobo Biochemicals
 CHIMERx
 Promega Corporation
 Bangalore Genei
 MRC-Holland
 EURx Ltd.