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ProGlycProt is a manually curated, exclusive repository of comprehensive information on experimentally characterized glycoproteins that belong to eubacteria and archaea For the benefit of users, ProGlycProt database (ProGlycProtdb) is arranged in following two sections:

1)	ProCGP (Prokaryotic Characterized Glycoproteins) defined as a compilation of prokaryotic glycoproteins for which at least one glycosite i.e. the glycosylated residue is identified through experiments like edman degradation, mass spectroscopy, site directed mutagenesis etc.
2)	ProUGP (Prokaryotic Uncharacterized Glycoproteins) defined as a list of prokaryotic glycoproteins in which glycosylation is known by experiments like aberrant migration on SDS PAGE, lectin binding, sugar specific staining but not the glycosites.

In addition, ProGlycProt provides for separate structure gallery, relevant links and two new tools that are developed keeping in mind the new sequon information obtained from literature on prokaryotic glycoproteins.

 

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Once thought restricted to eukaryotes, glycoproteins are now known to exist in almost all major phyla of prokaryotes. In last ten years, many new prokaryotic glycoproteins have been characterized for the precise location of glycosites, indicating a rising interest in the biology of protein glycosylation in prokaryotes. However, according to our search, currently none of the available protein informatic or glycoinformatic resource provides comprehensive and exclusive information about these experimentally identified or characterized glycoproteins of archaea and eubacteria. ProGlycProt is therefore designed to fill in this void. A long-term vision of ProGlycProt is to provide as much as possible experimental information available in published literature about these glycoproteins and to link these with the experimental information on mechanisms and genetic machinery involved in glycosylation of these proteins.

 

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To the best of our knowledge, ProGlycProtdb is the first manually curated, exclusive database of experimentally detected/characterized glycoproteins of prokaryotic origin. Though parts of the data available at ProGlycProt can be retrieved at SwissProt/ PDB/ BCSDB/ O- GlycBase yet unlike all these repositories ProGlycProt is an exclusive compilation of experimentally validated glycoproteins of prokaryotes only. Furthermore, ProGlycProtdb provides a lot of additional interesting information about a given glycoprotein like; full structure of attached glycan (IUPAC linear notation) as available from literature, information about glycosylation linked genes, experimental methods used to characterize a given glycoprotein, year of detection, year of characterization, observed sequon features and mannual annotation of all characterized glycoprotein sequences to incorporate mutational changes/ sequence conflicts/ in vitro or in vivo engineered sequence and visual display of glycosites. This first release of ProGlycProt contains information about at least 108 experimentally known glycoproteins that are absent in SwissProt on account of unsequenced genomes of the related organisms and as many as 69 proteins that includes peptides & engineered proteins for which glycosites are yet not annotated in any of the above mentioned protein databases.

 

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As of now and to the best of our knowledge, ProGlycProtdb represents the largest compilation of characterized prokaryotic glycoproteins available online consisting of entries from year 1974 to June 2011. Though we may not claim that ProCGP is a complete compilation, yet we have taken best efforts to incorporate all data that we could search through literature until we stopped finding further references in our searches made until June 30, 2011, in this first release. Further, we have tried to provide as accurate as possible information, yet we encourage users to refer the original literature cited along.
On the other hand, ProUGP is compiled from various brief seed compilations available in some of the published reviews (included in bibliography) and a few selected research publications. In view of increasing availability of huge data on detection of new glycoproteins using high throughput techniques like mass spectroscopy, we believe ProUGP would be enriched exponentially in future updates. We shall derive a different scheme to accommodate all such entries under ProUGP in future updates. In current release, what we have ensured is that at least all previously compiled prokaryotic glycoproteins are made available at ProUGP; at one place; in fully cross-referenced and searchable format, with additional information.

 

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In the last one decade, a lot of interest is generated in studying glycoproteins and mechanisms of their glycosylation in bacteria and archaea. In the first release, we have tried to provide all around information about a number of glycoproteins that are implicated in virulence, host pathogen interactions, immune modulation, disease diagnosis, and vaccination that microbiologists, clinicians, immunologists or even glycobiologists may find interesting. Similarly, we have included at least 7 glycoengineered proteins/ peptides of prokaryotic origin with known glycosites in ProCGP that may find attention of protein engineers. Further, data on glycosites can be of use for statistical analysis of sequence requirements/ preferences for glycosylation in prokaryotes

 

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Apart from continued compilations for bacterial and archaeal glycoproteins; in future updates, we aim at incorporating some or all of the following features in ProGlycProt:

¤	More structural and image inputs for glycan entries corresponding to each glycoprotein entry in ProCGP
¤	More experimental information about prokaryotic Oligosaccharyl Transferases (OSTs) and associated Glycosyl Transferases (GTs)
¤	To devise finer criteria to arrange large amount of glycoprotein entries detected by high throughput analysis like mass spectroscopy etc. under ProUGP and to facilitate better retrieval of biologically relevant and experiments oriented information about each entry.
¤	New tool(s) for glycoprotein/ sequence analysis or visualization