The EMBL nucleotide sequence database.

The EMBL Nucleotide Sequence Database (http://www.ebi.ac.uk/embl/) is maintained at the European Bioinformatics Institute (EBI) in an international collaboration with the DNA Data Bank of Japan (DDBJ) and GenBank at the NCBI (USA). Data is exchanged amongst the collaborating databases on a daily basis. The major contributors to the EMBL database are individual authors and genome project groups. Webin is the preferred web-based submission system for individual submitters, whilst automatic procedures allow incorporation of sequence data from large-scale genome sequencing centres and from the European Patent Office (EPO). Database releases are produced quarterly. Network services allow free access to the most up-to-date data collection via ftp, email and World Wide Web interfaces. EBI's Sequence Retrieval System (SRS), a network browser for databanks in molecular biology, integrates and links the main nucleotide and protein databases plus many specialized databases. For sequence similarity searching a variety of tools (e.g. Blitz, Fasta, BLAST) are available which allow external users to compare their own sequences against the latest data in the EMBL Nucleotide Sequence Database and SWISS-PROT.

Separation of chiral biodegradation intermediates of linear alkylbenzenesulfonates by capillary electrophoresis.

High-performance capillary electrophoresis (HPCE) with α-cyclodextrin as the chiral selector was applied to separate the enantiomers of p-sulfophenyl-2-butyrate (SP2B) and p-sulfophenyl-3-butyrate (SP3B), which occur as biodegradation intermediates of linear alkylbenzenesulfonates (LAS), the widely used anionic surfactants. With this analytical method, we studied the transformation of both SP3B enantiomers in a laboratory batch incubation with activated sewage sludge of a municipal wastewater treatment plant. (S)-(+)-SP3B and (R)-(-)-SP3B could be detected in mechanically treated sewage effluent. After enrichment on graphitized carbon black (Carbopack B), the extracts were analyzed by HPLC with UV diode array and fluorescence detection as well as by HPCE with UV diode array detection. Quantification of SP3B in a 24-h composite sample of primary sewage effluent yielded 34 µg/L (limit of detection, 0.1 µg/L) of the racemic mixture determined by HPLC and 18 µg/L of each enantiomer measured by HPCE (limit of detection, 1 µg/L).