Abstract

BackgroundThe type IV secretion system (T4SS) can be classified as a large family of macromolecule transporter systems, divided into three recognized sub-families, according to the well-known functions. The major sub-family is the conjugation system, which allows transfer of genetic material, such as a nucleoprotein, via cell contact among bacteria. Also, the conjugation system can transfer genetic material from bacteria to eukaryotic cells; such is the case with the T-DNA transfer of Agrobacterium tumefaciens to host plant cells. The system of effector protein transport constitutes the second sub-family, and the third one corresponds to the DNA uptake/release system. Genome analyses have revealed numerous T4SS in Bacteria and Archaea. The purpose of this work was to organize, classify, and integrate the T4SS data into a single database, called AtlasT4SS - the first public database devoted exclusively to this prokaryotic secretion system.DescriptionThe AtlasT4SS is a manual curated database that describes a large number of proteins related to the type IV secretion system reported so far in Gram-negative and Gram-positive bacteria, as well as in Archaea. The database was created using the RDBMS MySQL and the Catalyst Framework based in the Perl programming language and using the Model-View-Controller (MVC) design pattern for Web. The current version holds a comprehensive collection of 1,617 T4SS proteins from 58 Bacteria (49 Gram-negative and 9 Gram-Positive), one Archaea and 11 plasmids. By applying the bi-directional best hit (BBH) relationship in pairwise genome comparison, it was possible to obtain a core set of 134 clusters of orthologous genes encoding T4SS proteins.ConclusionsIn our database we present one way of classifying orthologous groups of T4SSs in a hierarchical classification scheme with three levels. The first level comprises four classes that are based on the organization of genetic determinants, shared homologies, and evolutionary relationships: (i) F-T4SS, (ii) P-T4SS, (iii) I-T4SS, and (iv) GI-T4SS. The second level designates a specific well-known protein families otherwise an uncharacterized protein family. Finally, in the third level, each protein of an ortholog cluster is classified according to its involvement in a specific cellular process. AtlasT4SS database is open access and is available at http://www.t4ss.lncc.br.

Highlights

  • The type IV secretion system (T4SS) can be classified as a large family of macromolecule transporter systems, divided into three recognized sub-families, according to the well-known functions

  • The first level comprises four classes that are based on the organization of genetic determinants, shared homologies, and evolutionary relationships: (i) F-Type IV Secretion System (T4SS), (ii) P-T4SS, (iii) I-T4SS, and (iv) GI-T4SS

  • Type IV Secretion System (T4SS) is one of the most functionally diverse, both in terms of the transported substrate (DNA, proteins, or DNA-protein complex) and the projected recipients [7]. According to this high range, three types of T4SS have been described: (i) the conjugation system [8]; (ii) the effector translocator system [9]; and (iii) the DNA release or uptake system

Read more

Summary

Introduction

The type IV secretion system (T4SS) can be classified as a large family of macromolecule transporter systems, divided into three recognized sub-families, according to the well-known functions. Type IV Secretion System (T4SS) is one of the most functionally diverse, both in terms of the transported substrate (DNA, proteins, or DNA-protein complex) and the projected recipients (receiver cells or extracellular medium) [7]. According to this high range, three types of T4SS have been described: (i) the conjugation system (translocates DNA-protein substrates to recipient cells via a contact-dependent process) [8]; (ii) the effector translocator system (delivers proteins or other effector molecules to eukaryotic target cells) [9]; and (iii) the DNA release or uptake system (translocates DNA to or from the extracellular milieu) [10]. Other proteins not needed for the assembly of the channel are required for the proper function of the system [11]

Objectives
Findings
Discussion
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.