Reactions Databases Current Literature

Substance information such as chemical structures, molecular formulas, and chemical names Is stored in the REGISTRY database. This is the largest collection of chemical substance Information worldwide (see Section 3,1,2), While REGISTRY contains information on specific substances, generic substances are covered by MARPAT, Generic structures are called Markush structures after the American chemist Eugene Markush, who introduced these structures in the patent literature in 1924, MaRPAT comprises generic structures from the patent literature since 1988 (see Structure Representation). Chemical reactions or molecular transformations are covered by CASREACT (see also Reaction Databases). CASREACT has been indexed since 1985 and currently holds 2.9 million chemical reactions from the chemical and patent literature,... 

This is a combined archival database with 171629 reactions originating predominantly from about 300 Journals and some patents. It comprises the Theilheimer databa.se (46785 reactions 1946-1980), the core database from the former ORAC system (about 65 000 reactions, mainly 1980-1991), and several databases produced by MDL (CLF Current Literature File 36600 general synthetic reactions 1983-1991. CHIRAS 13 200 asymmetric reactions 1975-1991. Metalysis 12000 metal-mediated reactions 1974-1991). Although the time coverage of RefLib does really start at 1946, the onset of Theilheimer, there are almost 4000 reactions with pre-1946 references (2600 with literature only before that year). 

As with chemical synthesis, the first step when prospecting for a particular biotransformation is to perform a literature search to check whether a suitable precedent has been described. Extensive technical literature resources in the public domain provide both examples of specific enzyme-catalysed reactions and descriptions of transformations where enzyme activity is inferred if not explicitly described. Currently, searches of online databases such as PubMed reveal over 2000 new publications per annum in the subject of enzyme catalysis (excluding reviews). 

A much more ambitious database that builds on the IUBMB classification is BRENDA, maintained by the Institute of Biochemistry at the University of Cologne. In addition to the data provided by the ENZYME database, the BRENDA curators have extracted a large body of information from the enzyme literature and incorporated it into the database. The database format strives to be readable by both humans and machines. The categories of data stored in BRENDA comprise the EC-number, systematic and recommended names, synonyms, CAS-registry numbers, the reaction catalyzed, a list of known substrates and products, the natural substrates, specific activities, KM values, pH and temperature optima, cofactor and ion requirements, inhibitors, sources, localization, purification schemes, molecular weight, subunit structure, posttranslational modifications, enzyme stability, database links, and last but not least an extensive bibliography. Currently, BRENDA holds entries for approximately 3500 different enzymes. 

The database may be purchased from NIST, Standard Reference Data, Building 221/Room A320, Gaithersburg, MD 20899. This database runs locally on MS-DOS compatible computers. The current version contains 14,000 rate determinations on 10,800 reactions involving 7800 chemical species. The database can be searched for reactants, products, citation, or author. An updated version, compiling data from the literature through the end of 1994, will be released shortly. 

ISI do direct abstracting from the primary literature to produce the Current Chemical Reactions (CCR) database. 

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