TrEMBL is a supplement to SWISS-PROT that contains computer annotated translations of EMBL. TrEMBL contains the translations of all coding sequences (CDS) present in the EMBL Nucleotide Sequence Database, which are not yet integrated into SWISS-PROT. When entry annotation and verification is complete, it is moved from TrEMBL to SWISS-PROT (assuming the entry does not already exist, in which case they will be merged). Since preparing entries for SWISS-PROT is so time consuming, TrEMBL basically attempts to bridge the gap, and provide a redundant database of (less extensively) annotated translations of coding sequences (CDS) that are not listed in SWISS-PROT.
TrEMBL has two main sections.
SW-TrEMBL (SWISS-PROT TrEMBL), which contains sequences that are en route to SWISS-PROT.
REM-TrEMBL stores the remaining entries. This includes entries specifically excluded from SWISS-PROT, such as the many variations of immunoglobulins and T-cell receptors, synthetics sequences, fragments of less than eight amino acids, CDS from patent applications and EMBL CDS translations where the curators have strong evidence that the nucleotide does not code for real proteins.
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