It is widely acknowledged that developing a mechanism to handle multiple databases in an integrated manner is key to making glycomics accessible to other -omic disciplines. The National Academy of Science published a report called “Transforming Glycoscience: A Roadmap for the Future” that exemplifies the hurdles and problems faced by the Glycomics research community due to the disconnected and incomplete nature of existing databases . Within the last decade, a large number of carbohydrate structure (sequence) databases have become available on the web, all providing their own unique data resources and functionalities . After the conclusion of the CarbBank project , the German Cancer Research Center used the available data to develop their GLYCOSCIENCES.de database , which in general focuses on the three-dimensional conformations of carbohydrates. KEGG GLYCAN was added to the KEGG resources as a new glycan structure database that is linked to their genomic and pathway information . The Consortium for Functional Glycomics also developed a glycan structure database to supplement their data resources storing experimental data from glycan array, glycan profiling from mass spectrometry, glyco-gene knockout mouse and glyco-gene microarray . In Russia, the Bacterial Carbohydrate Structure Database (BCSDB) was developed, which contains carbohydrate structures from bacterial species collected from the scientific literature . Additionally, small databases used in local laboratories have been developed, and so the GlycomeDB database was developed to integrate all the records in these databases to provide a web portal that allows researchers to search across all supported databases for particular structures . The developers of GlycomeDB were a part of the EUROCarbDB project, which was an EU-funded initiative for developing a framework for storing and sharing experimental data of carbohydrates . Several resources were developed under the EUROCarbDB framework including, a database for organizing monosaccharide information was developed, called MonosaccharideDB  and the HPLC-focused database GlycoBase . MonosaccharideDB is an important database for integrating carbohydrate structures from different resources, since oftentimes different representations are used for the same monosaccharides. Unfortunately, funding-support for the EUROCarbDB project ended, however the data resources and software, which are all available as open source software, were taken on by the UniCarbKB project . Meanwhile in Japan, the Japan Consortium for Glycobiology and Glycotechnology Database (JCGGDB) was developed to integrate all the carbohydrate resources in Japan . However, despite all of these efforts to develop useful and valuable glycomics databases, a lack of interoperability is hampering the development of ‘mashup’ applications that are capable of integrating glycan related data with other -omics data.
Almost all databases mentioned above provide their information using web pages restricting the query possibilities to the limited search options provided by the developers. In addition only a few databases provide web services that allow retrieval of data in a machine-readable non-HTML format. The few implemented web service interfaces return proprietary non-standard formats making it hard to retrieve and integrate data from several resources into a single result. Despite some efforts to standardize and exchange their data [14, 15], most glycomics databases are still regarded as “disconnected islands” . Standardization of carbohydrate primary structures is more difficult than genomics or proteomics, mainly because of the inherent structural complexity of oligosaccharides exemplified by complex branching, glycosidic linkages, anomericity and residue modifications. Individual databases developed their own formats to cope with these problems and encode glycan primary structures in a machine readable way .