ht. J. Biochem. Vol. 25, No. 8, pp. 1215-1217, 1993 Pergamon Press Ltd. Printed in Great Britain.
BOOK REVIEWS
Chapman & Hall Chemical Database Dictionary of Nat114 Products on CD-ROM. E2750 (Academic Users) first yearf1750; subsequent years 095. ISSN 0966 2146. For many years Chapman & Hall have published printed dictionaries of chemical compounds. The information in their Dictionaries of Organic Compounds, Alkaloids, Antibiotics, Steroids, Terpenoids and other material has been combined in this electronic database product. The information available for each compound includes: chemical structure; CAS registry number; synonyms; physical description; melting point; boiling point; freezing point; relative density; refractive index; optical rotation; solubility; dissociation constant for acids; compound type; use or importance; bioloical source; biological and pharmacological activity; and references. That is, therefore, a rich and extensive source of information. The development of extensive crossindexing and searching capabilities in this CD-ROM database significantly increases the utility of the information. To use the database on IBM-compatible 386 or 486 based PC with 4 Mbytes of RAM and 5 Mbytes free disk space is required. A CD-ROM drive accessed via the Microsoft CD-ROM extensions (MSCDEX) is also needed. Finally, the software runs under Microsoft Windows 3.0 or 3.1M which should already be installed. The demonstration software supplied for this review was loaded from floppy-disk onto hard-disk. It contained the full interrogation software but a small sub-set of the database; 400 compounds against over 80,000 in the full version. The fact that the database was held on hard-disk, rather than the slower CD-ROM drive of the full version, would enhance the time taken to access the data. There are two ways of searching the database. First, a text based approach, using the HeadfastrM system, allows rapid screening of matching entities. Any of the entry fields can be used, and logically combined with any other field(s). For example, it is very easy to search for a possible compound by melting point and species of isolation. The report screen has the option of showing the structure of each compound. The second way to search the database is based on locating compounds with matching chemical sub-structures. This is performed using the PsiBaseTM Structure Searching software. Searching in this mode is simple. You are presented with a drawing screen as found in chemical drawing packages where a structural element can be constructed. Once the structure is completed clicking on the search button initiates the search. Naturally this search is slower than the text based search. A search for structures containing a pyridine ring in the 400 sample demonstration database took about one minute on my 20 MHZ 386. As the search comprises a first rapid screen followed by an exhaustive atom by atom second stage the scale up time from 400 entries to 80,000 will not be linear but could take a considerable time. It is a simple step to combine the results from both search strategies. This package does offer considerable advantages over the traditional paper-based dictionaries. For search strategies more complex than merely looking up a compound the ability to combine search results
saves a great deal of time. The ability to do both text and sub-structure searches and combine the results makes this a powerful information system. The software has been carefully designed and as a result is easy to use. The one disappointment is the quality of the output obtained when a print out is requested. It would appear that the package generates its own fonts, which are low resolution matrix characters, rather than using the native fonts supported by WindowsTM, TrueTypeTM or ATMTM. The overall conclusion is that this is a useful resource. It is based on primary data that already has its own reputation; the current significant offering aids accessibility to that information. Each user and institution, however, will have to make their own judgement as to whether the cost involved for hardware and software are justifiable. Bioactive Spin LabelsEdited by R. I. ZHDANOV. 636 pp. 1992. Springer Verlag, Berlin. DM 348. The study of the reactions of free radicals have been greatly facilitated by the development of the stable nitroxyl radicals. These have been used as spin labels (S-L) and probes in biochemical and pharmacological investigation. This volume describes their use in; S-L medicines, enzymes and pharmaceuticals; triacetonamine; redox processes; biomembranes; relaxation processes; spin exchange; S-L phospholipids; S-L protein-lipid interactions; S-L organophosphorus compounds; S-L sugars and nucleosides; S-L leucine aminopeptides; photoaffinity S-L; S-L platelet plasma membranes and nitroxyl aggregating inhibitors; anti-ischaemic effects of nitroxyl bioantioxidants; S-L of cancer membranes; aminoxyl S-L in clinical analysis; aminoxyl radicals as MRI contrast agents. Multidisciplinary Approaches to Cholinesterase FunctionsEdited by A. SCHAFFERMANand B. VELAN. 293 pp. 1992. Plenum Press, New York. $85. The structure of the catalytic subunit of AChE has recently been resolved. There have also been major advances in the molecular genetics of AChE using recombinant DNA technology. The three dimensional structure of Torpedo AChE and different enzymes sharing the common folding pattern have also been determined. The reviews are grouped into three main sections.
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(1) Molecular
polymorphism; [biosynthesis, binding to muscle cells, subunit assembly and glycosylation, genetic variation, butyryl ChE, nematode AChE, Drosophila AChE, insecticide resistant AChE]. relationship; [3-D structure, se(2) Structure-function quence alignment, ammonium binding sites, labelling by platinum chloride, cryptic catalysis, functional domains, site directed mutagenesis]. role and clinical applications; [AChE (3) Physiological regulation, compartmentalization, neurogenesis, AChE as a modulatory neuroprotein, Alzheimer’s disease, et&t of carbamates, autoimmunity, hemopoietic cell division, organophosphate toxicity].