Bujnicki lab - Home
  • RNA has recently emerged as an attractive target for new drug development. Our team is developing new methods to study the interactions between RNA and ligands. Recently, we have developed a new machine learning method called AnnapuRNA to predict how small chemical molecules interact with structured RNA molecules. Research published in PLoS Comput Biol. 2021 Feb 1;17(2):e1008309. doi: 10.1371/journal.pcbi.1008309. Read More
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About Laboratory Of Bioinformatics And Protein Engineering

Our group is involved in theoretical and experimental research on nucleic acids and proteins. The current focus is on RNA sequence-structure-function relationships (in particular 3D modeling), RNA-protein complexes, and enzymes acting on RNA.
 
We study the rules that govern the sequence-structure-function relationships in proteins and nucleic acids and use the acquired knowledge to predict structures and functions for uncharacterized gene products, to alter the known structures and functions of proteins and RNAs and to engineer molecules with new properties.
 
Our key strength is in the integration of various types of theoretical and experimental analyses. We develop and use computer programs for modeling of protein three-dimensional structures based on heterogenous, low-resolution, noisy and ambivalent experimental data. We are also involved in genome-scale phylogenetic analyses, with the focus on identification of proteins that belong to particular families. Subsequently, we characterize experimentally the function of the most interesting new genes/proteins identified by bioinformatics. We also use theoretical predictions to guide protein engineering, using rational and random approaches. Our ultimate goal is to identify complete sets of enzymes involved in particular metabolic pathways (e.g. RNA modification, DNA repair) and to design proteins with new properties, in particular enzymes with new useful functions, which have not been observed in the nature.
 
We are well-equipped with respect to both theoretical and experimental analyses. Our lab offers excellent environment for training of young researchers in both bioinformatics and molecular biology/biochemistry of protein-nucleic acid interactions.


More Good Science

MetaServer
The GeneSilico MetaServer is a gateway to a number of third-party methods for protein structure prediction (identification of domains, secondary structure prediction, fold-recognition, and finally, 3D model generation). Users can submit a protein sequence (or alignment) by a single click, then analyze the summary of results generated by many methods, and finally predict the protein structure according to the "consensus" approach.
 

FRankenstein3D 
This tool builds protein models by recombining fragments of Fold-Recognition alignments. Users can select a set of alignments from the output of the MetaServer or provide their own alignments. The program will generate alternative models, identify fragments that either exhibit consensus conformation in different models or - in the absence of consensus - show the relatively best compatibility of amino acids with the environment of the rest of the model. These fragments will be recombined to create a hybrid model, which will be further optimized by trying alternative alignments in non-consensus regions to improve the sequence-structure compatibility.
 

COLORADO3D
This simple server facilitates visual presentation of three-dimensional (3D) protein structures. It is a gateway to a number of methods for evaluation of protein structure (ANOLEA, PROSAII, PROVE or VERIFY3D), but also identifies buried residues and depicts sequence conservation. As an input, it takes a PDB file and, optionally, a multiple sequence alignment. As an output, the server returns a file in which the B-factor column is replaced with values of the chosen parameter (structure quality, residue burial or conservation). These values can be visualized as colors using structure viewers such as RASMOL or SWISS PDB VIEWER.
 

FILTREST3D
This is an "alpha" version of a server for discrimination of a large number of alternative models of protein structure against a set of restraints derived from low-resolution experimental analyses (such as cross-linking, mutagenesis, circular dichrosm etc.) as well as from computational predictions (e.g. solvent accessibility, amino acid contact maps).
 

STRUCLA
While most phylogenetic methods calculate trees based on sequence alignments, this server (STRUcture CLAssification) allows to use protein structures. The prefereed input is an alignment of protein coordinates exported from SWISS PDB VIEWER. The user specifies the distance cutoff and selects which measures should be used to calculate the "evolutionary distances" between the protein structures. The server returns series of unrooted trees in the NEXUS format and corresponding distance matrices, as well as a consensus tree. This method is most useful in the 'twilight zone of homology', where amino acid sequences are too diverged to provide reliable relationships.
 

CompaRNA
The CompaRNA web server provides a continuous benchmark of automated standalone and web server methods for RNA secondary structure prediction. It has been inspired by the EVA and Livebench servers for benchmarking of protein structure prediction tools, which have greatly contributed to progress in the field of structural bioinformatics. The aim of CompaRNA is to assess the state of the art in RNA structure prediction, provide a detailed picture of what is possible with the available tools, where progress is being made and what major problems remain. The CompaRNA server is a valuable resource for all researchers who focus their attention on the usage and development of RNA structure prediction methods.
 

ModeRNA server 
ModeRNA server is an online tool for RNA 3D structure modeling by the comparative approach, based on a template RNA structure and a user-defined target-template sequence alignment. It offers an option to search for potential templates, given the target sequence. The server also provides tools for analyzing, editing and formatting of RNA structure files. It facilitates the use of the ModeRNA software and offers new options in comparison to the standalone program.
 

MetalionRNA server
MetalionRNA is a web server for the prediction of metal ions (magnesium, sodium, and potassium) in RNA 3D structures, based on a statistical potential inferred from the analysis of binding sites observed in experimentally solved RNA structures. The server is also capable of predicting Mg2+-binding sites for DNA structures.
 

MetaLocGramN server
The MetaGramLocN is a method for subcellular localization prediction of Gram-negative proteins. The MetaGramLocN is a gateway to a number of primary prediction methods (various types: signal peptide, beta-barrel, transmembrane helices and subcellular localization predictors). The MetaGramLocN integrates the primary methods and based on their outputs provides overall consenus prediction. To make a prediction for your protein sequence use Submit or SOAP client In our benchmark, the MetaLocGramN performed better in comparison to other SCL predictive methods, since the average Matthews correlation coefficient reached 0.806 that enhanced the predictive capability by 12% (compared to PSORTb3).
 

RIBER/DIBER
Co-crystallization experiments of proteins with nucleic acids do not guarantee that both components are present in the crystal. While working as a PhD student with Matthias Bochtler, Grzegorz Chojnowski developed DIBER - a method with which to predict crystal content (DNA? protein? or both?) from the diffraction data. Now, we have together developed RIBER, which should be used when protein and RNA are in the crystallization drop. The combined RIBER/DIBER suite builds on machine learning techniques to make reliable, quantitative predictions of crystal content for non-expert users and high throughput crystallography. RIBER/DIBER requires diffraction data to at least 3.0 Å resolution in MTZ or CIF format.
 

MinkoFit3D
MinkoFit3D is a method for fitting macromolecular assemblies or their components into electron density maps. Our approach is based on finding “tight passages” inferred from the Minkowski sum boundary of two polyhedral surfaces of the structure and its map. Following the initial fit, either a robust brute-force or a genetic algorithm is used to build an initial assembly, and multi-body refinement is applied in direct electron density space. 

 

GDFuzz3D
GDFuzz3D is a method for protein tertiary structure retrieval from a contact map.  It can handle binary (i.e. native) contact maps but the algorithm is designed to have predicted contact maps on input. GDFuzz3D makes use of a new non Euclidean distance function as explained in the publication. Then it uses Multi-Dimensional Scaling algorithm to produce a crude 3D model. Subsequently, other bioinformatics programs are used in order to refine the model, i.e. Modeller and Refiner. The results are sent by email as a PDB file.

 

PROTMAP2D v. 1.2.2

Two-dimensional maps of contacts summarize interactions between amino acids in the structure. They reveal characteristic patterns of interactions between secondary and super-secondary structures and are very attractive for visual analysis. The overlap of the residue contact maps of two structures can be easily calculated, providing a sensitive measure of protein structure similarity.

PROTMAP2D is a tool for calculation, visualization and comparison of contact maps. It can be used for quantitative and qualitative characterization of differences and similarities between alternative models of the same protein, e.g. members of the ensemble calculated from the results of the nuclear magnetic resonance (NMR) analysis, crystal structures solved under different conditions, theoretical models calculated with different programs, or series of conformations obtained in the course of  molecular dynamics (MD) simulations. PROTMAP2D allows analyzing multimeric proteins, and can be used to visualize intermolecular contacts in protein-protein complexes.

The MacOSX and Windows standalone binary versions of PROTMAP2D are available for download. Linux binary bundle has some prerequisites to install (see the README file enclosed for details).

Program's ftp directory:
https://genesilico.pl/software/protmap2d/

PROTMAP2D is available for academic users under the license (details enclosed in the license file to be found in each package). Non-academic users and those, who do not accept the license, may NOT download or use the software. A separate commercial license will be issued in the future.

We would greatly appreciate feedback from users, including compliments, bug reports, suggestions for new options to be implemented, etc. Send your messages to Michal J. Pietal, the principal developer of PROTMAP2D.

 

Important Notice: After most recent Windows7 update (SP1) we observed that PROTMAP2D ceased to work on Windows7.  In such case, we advise the users to use either other version, on either other systems (other Windows systems seem unaffected).  A temporary workaround is not to install SP1 on Windows7, however we do not recommend this as it might cause exposing the system to certain vulnerabilities.  We expect that this issue will be adressed by Windows7 SP2.

Technical Notice:  Because since the software was originally built and published, a number of Linux/BSD and macOS systems were made available, the respective target builds may no longer be supported.  Thus in order to use the program, we encourage the users to use either the Windows build natively or launch one with the use of Wine / Darwine frameworks (https://www.winehq.org , http://darwine.sourceforge.net ), under most recent Linux/BSD or macOS flavours, respectively.  These auxiliary tools been mentioned are freeware and easily installable, so no additional license or substantial effort is needed.

 

Please cite:
Pietal, M. J., Tuszynska, I., & Bujnicki, J. M. (2007). PROTMAP2D: visualization, comparison and analysis of 2D maps of protein structure. Bioinformatics, 23(11), 1429-1430.
 


PROTMAP2D gallery

A simple contact map of a dimer 1acv.  Secondary structure visible (red bars- helices, green bars- sheets) was read out from the pdb file



 

A distance map of the first model of an NMR ensemble 1aca

 

Distance map of 1aca, cropped by lower and upper contact threshold, 7 and 20 A, respectively

 

 

A comparison two models of I-TevI catalytic domain.  Right-upper: x-ray model (Van Roey, et al., 2002), left-lower: de-novo prediction (Bujnicki, et al., 2001)

 

A two-layer contact map on a 1acv ensemble.  White contacts exist in all models, while grey exist only in some

 

Frequency contact map of a MD unfolding trajectory. Left-lower contacts co-exist in a native (starting) structure, whilst right-upper do not

 

A comparison of two MD unfolding trajectories (same parameters, temperature set to 300 and 500 K).  Direction of the colour shift show stability of the structure during time (x and y axes)

 

A contact map similarity calculated for MD trajcetory



500.mpg

A MD trajectory movie exported to a file (feature available on windows and linux only)

NOTE: To open this file you not only need an appropriate MPEG file player, but also adequate video codecs installed. An example cross-platform tool capable of playing PROTMAP2D movie files is VLC program to be downloaded from http://www.videolan.org/vlc/


RNAmap2Da tool for visualization of 2D maps of RNA structures

by Michał J. Piętal, Natalia Szóstak, Kristian Rother and Janusz M. Bujnicki
 

The resolved structures of RNA highlight the crucial role these molecules play in many biological processes. That is why it is important to extract all the information from the available data; in order to do that it is extremely important to develop new tools and methods for examination of those structures. Two-dimensional maps of distances and contacts between residues in the structure may be useful for many analyses, as the former contain sufficient information to restore the 3D representation, while the latter reveal characteristic patterns of interactions between secondary and super-secondary structures and are very attractive for visual analyses.

 

RNAmap2D v. 1.7.5, a major update for Linux, Windows and MacOSX is available at this location.  Windows and OSX versions are now standalone programs.  Before installing the program on other platform, please refer to README and User's Manual documents.

 

What is RNAmap2D?
 

Based on the previous program PROTMAP2D for visualisation of contacts in protein structures, we developed a new tool, RNAMAP2D, dedicated to the analysis of contact maps of RNA structures and protein – RNA complexes. Our program deals with modified base pairs which are very frequent in RNA and includes ligands and ions which plays key roles in forming and stabilizing RNA structures. What is more, it is possible to show on the computed map whether some of the identified contacts are recognized as belonging to one of the 12 base pairs families, are canonical Watson – Crick pairs, or are 4 classes of stacking interactions. The overlap of the 2D maps of two structures can be easily calculated, providing a measure of RNA structure similarity.

Technical Notice:  Because since the software was originally built and published, a number of Linux/BSD and macOS systems were made available, the respective target builds may no longer be supported.  Thus in order to use the program, we encourage the users to use either the Windows build natively or launch one with the use of Wine / Darwine frameworks (https://www.winehq.org , http://darwine.sourceforge.net ), under most recent Linux/BSD or macOS flavours, respectively.  These auxiliary tools been mentioned are freeware and easily installable, so no additional license or substantial effort is needed.


Please cite:


Pietal, M. J., Szostak, N., Rother, K. M., & Bujnicki, J. M. (2012). RNAmap2D–calculation, visualization and analysis of contact and distance maps for RNA and protein-RNA complex structures. BMC bioinformatics, 13(1), 333.
 

 

RNAmap2D gallery
 

A rough set calculated for an ensemble code 1JOX (left). White contacts are those existing in all 24 models while grey colour indicates contacts appearing partially so in some models but not in the others. please note that RNA secondary structure was computed and displayed (pink and violet dots). The 3D structure is shown on the right.

 

A picture of an RNA-protein complex: double-stranded RNA binding domain of S. cerevisiae RNAse III in complex with an AAGU tetraloop hairpin (PDB 2LBS, model 1). 3D structure is shown below the contact map. First part of the picture (larger square, shown in yellow) is a contact map (all-atom metric, 3.5 A) of complex-containing protein. The remaining part (smaller square, shown in blue) unveils contact map within the RNA structure (all-atom metric, 3.5 A). Note that group of contacts from rightmost upper part of the picture (and symmetrically, shown in orange) are those of the protein-RNA interface. Colour bars within protein section indicate secondary structure: red (helix) and green (strand), RNA secondary structure is present in this picture as well.

 

Distance map of the 1EHZ RNA molecule. Normally, ligand and ion pseudochain is also present (see: below), but the user can choose specific chains for the purpose of final map calculation. White colour indicates close distance of the base pairs while dark grey pairs are considered spatially distant. 3D structure is also shown.

 

In this picture an example is shown of RNAmap2D colouring capabilities. Panel shown on the right was used here to indicate several types of pairing/ stacking/ other particles. The resulting map is on the left, main part being a 1EHZ RNA molecule, smaller square is a set of ligands and ions contacts, rightmost upper (and symmetrical) block indicates contacts between nucleic acid residua and other particles. Note that all kinds of pairings and stacking is determined before the panel is shown thus making some options disabled.

 


Another 1EHZ structure picture, this time showing only specific contacts that is, any pairings (red), any stacking (green) and any ion or ligand contacts (pink). All the remaining contacts are not shown by setting the colour to black.