Enzymes diagnostic applications

Directed evolution will contribute substantially to our understanding of substrate discrimination by polymerases and, thus, will enable use of these enzymes as important tools in a variety of synthetic and diagnostic applications. 

These enzymes are extraordinarily abundant over 1200 restriction endonucleases had been isolated and characterized by early 1990. Of three classes defined, type II restriction enzymes, which generally cut within their recognition sequences, have found uses in a host of biomedical research and diagnostic applications to be discussed below. Type 1 enzymes cut nonspecifically many nucleotides distal to specific recognition sequences and contain both restriction enzyme and DNA modification (see below) activities on different subunits of multienzyme complexes. Type III restriction enzymes share the multienzyme aspeas of type I enzymes but vary in other properties such as ATPase activity and cofactor requirements. 

Biocatalysts Biocatalysts Ltd Main Avenue, Treforest Industrial Estate Pontypridd, Wales, CF37 5UD United Kingdom Tel. +44 (0)1443843712 Fax +44 (0) 1443841214 Email sales biocats.com http //www.biocatalysts.com Producer and distributor of enzymes for use in industrial and diagnostic applications. 

The most common type of capture molecules used on a protein chip are antibodies, though other proteins, such as peptides, nucleic acids, enzymes and receptors, have been spotted on to chips. Protein chips can be difficult to prepare, as the proteins need to be kept in an active state, in a high concentration and in a moist environment. Typical samples investigated are cell lysates for general research or blood and urine for diagnostic applications. Fluorescence detection methods are preferred since they are simple and sensitive. Other detection methods, where labelling is not required, can take the form of SELDl or AFM. 

Hoffman, A.S. et ah. Immobilization of enzymes and antibodies to radiation grafted polymers for therapeutic and diagnostic applications, Radiat. Phys. Chem., 27, 265, 1986. 

Chamoles, N. A. Determination of the activity of lysosomal enzymes in dried body fluid or tissue sample for diagnostic applications. U.S. Pat. Appl. Publ. US 2004166554, 2004 Chem. Abstr. 2004, 141, 202270. 

A review of biochips and microarrays [4] considers requirements for biochemical and medical diagnostic applications, focusing on sihcon manufacturing technology coupled with magnetic beads, nucleic acid recognition, and enzyme catalysis. This review includes optical as well as electrochemical measurement methods. 

Besides recombinant whole cells, crude extracts are also widely applied, and typically most of the enzyme formulations used for biotransformations in organic synthesis are crude extracts or partially purified proteins rather than highly purified enzymes (which are more needed in the field of diagnostic applications). 

---