Published online 29 October 2010 Nucleic Acids Research, 2011, Vol. 39, Database issue D653–D657 doi:10.1093/nar/gkq1058 ArachnoServer 2.0, an updated online resource for spider toxin sequences and structures Volker Herzig1, David L. A. Wood 1 , Felicity Newell2, Pierre-Alain Chaumeil2, Quentin Kaas1, Greta J. Binford3, Graham M. Nicholson4, Dominique Gorse2 and Glenn F. King1,* 1Institute for Molecular Bioscience, 2Queensland Facility for Advanced Bioinformatics, The University of Queensland, Brisbane, Australia, 3Department of Biology, Lewis and Clark College, Portland, Oregon, USA and 4Department of Medical and Molecular Biosciences, University of Technology, Sydney, Australia Received August 15, 2010; Revised October 11, 2010; Accepted October 13, 2010 ABSTRACT ArachnoServer (www.arachnoserver.org) is a man- ually curated database providing information on the sequence, structure and biological activity of protein toxins from spider venoms. These proteins are of interest to a wide range of biologists due to their diverse applications in medicine, neuroscience, pharmacology, drug discovery and agriculture. ArachnoServer currently manages 1078 protein sequences, 759 nucleic acid sequences and 56 protein structures. Key features of ArachnoServer include a molecular target ontology designed specifically for venom toxins, current and historic taxonomic information and a powerful advanced search interface. The following significant improvements have been implemented in version 2.0: (i) the average and monoisotopic molecular masses of both the reduced and oxidized form of each mature toxin are provided; (ii) the advanced search feature now enables searches on the basis of toxin mass, external database accession numbers and publication date in ArachnoServer; (iii) toxins can now be browsed on the basis of their phyletic specificity; (iv) rapid BLAST searches based on the mature toxin sequence can be performed directly from the toxin card; (v) private silos can be requested from research groups engaged in venoms-based research, enabling them to easily manage and securely store data during the process of toxin discovery; and (vi) a detailed user manual is now available. INTRODUCTION The growing realisation that most venomous animals possess a complex repertoire of protein toxins with potential pharmaceutical and agrochemical applications has led to an exponential increase in the rate of toxin discovery (1). Several databases have been speciﬁcally developed to facilitate retrieval of information about these toxins, such as Tox-Prot (2) and the Animal Toxin Database (ATDB) (3). These databases are critical for comparison of toxins across different groups of venomous animals but they typically lack the rich information content of manually curated databases that deal with speciﬁc subsets of animal toxins, such as ConoServer (4), which provides information about toxins from marine cone snails. Spiders are the most evolutionarily successful venomous animals and the most abundant terrestrial predators. Their remarkable success is due in large part to their evolution of a pharmacologically complex venom that ensures rapid subjugation of prey. Most spider venoms are dominated by disulﬁde-rich peptide toxins that typically have high afﬁnity and selectivity for speciﬁc subtypes of ion channels and receptors, making them particularly valuable from a pharmacological and drug discovery perspective (5–8). Spider venoms are likely to contain >10 million bioactive peptides based on the extraordinary taxonomic diversity of spiders, with the number of extant species predicted to be more than 100 000 and the demonstration that some venoms contain more than 1000 unique peptides (5). This is a larger pharmacopeia than that of all other venomous animals combined. Prior to the introduction of ArachnoServer 1.0 (9), no publicly accessible database existed speciﬁcally for *To whom correspondence should be addressed. Tel: +61 7 3346 2025; Fax: +61 7 3346 2101; Email: glenn.king@imb.uq.edu.au The authors wish it to be known that, in their opinion, the ﬁrst two authors should be regarded as joint First Authors. The Author(s) 2010. Published by Oxford University Press. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/ by-nc/2.5), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.