Lichenicidin rational site-directed mutagenesis library: A tool to generate bioengineered lantibiotics

Lantibiotics are ribosomally synthesized and posttranslationally modified antimicrobial peptides that arise as an alternative to the traditional antibiotics. Lichenicidin is active against clinically relevant bacteria and it was the first lantibiotic to be fully produced in vivo in the Gram-negative host Escherichia coli. Here, we present the results of a library of lichenicidin mutants, in which the mutations were generated based on the extensive bibliographical search available for other lantibiotics. The antibacterial activity of two-peptide lantibiotics, as is lichenicidin, requires the synergistic activity of two peptides. We established a method that allows screening for bioactivity which does not require the purification of the complementary peptide. It is an inexpensive, fast and user-friendly method that can be scaled up to screen large libraries of bioengineered two-peptide lantibiotics. The applied system is reliable and robust because, in general, the results obtained corroborate structure–activity relationship studies carried out for other lantibiotics.     

MULTBLAST: A web application for multiple BLAST searches

Basic Local Alignment Search Tool, (BLAST) allows the comparison of a query sequence/s to a database of sequences and identifies those sequences that are similar to the query above a user-defined threshold. We have developed a user friendly web application, MULTBLAST that runs a series of BLAST searches on a user-supplied list of proteins against one or more target protein or nucleotide databases. The application pre-processes the data, launches each individual BLAST search on the University of Nevada, Reno''s-TimeLogic DeCypher® system (available from Active Motif, Inc.) and retrieves and combines all the results into a simple, easy to read output file. The output file presents the list of the query proteins, followed by the BLAST results for the matching sequences from each target database in consecutive columns. This format is especially useful for either comparing the results from the different target databases, or analyzing the results while keeping the identification of each target database separate.

Availability

The application is available at the URLhttp://blastpipe.biochem.unr.edu/     

BiNChE: A web tool and library for chemical enrichment analysis based on the ChEBI ontology

Background

Ontology-based enrichment analysis aids in the interpretation and understanding of large-scale biological data. Ontologies are hierarchies of biologically relevant groupings. Using ontology annotations, which link ontology classes to biological entities, enrichment analysis methods assess whether there is a significant over or under representation of entities for ontology classes. While many tools exist that run enrichment analysis for protein sets annotated with the Gene Ontology, there are only a few that can be used for small molecules enrichment analysis.

Results

We describe BiNChE, an enrichment analysis tool for small molecules based on the ChEBI Ontology. BiNChE displays an interactive graph that can be exported as a high-resolution image or in network formats. The tool provides plain, weighted and fragment analysis based on either the ChEBI Role Ontology or the ChEBI Structural Ontology.

Conclusions

BiNChE aids in the exploration of large sets of small molecules produced within Metabolomics or other Systems Biology research contexts. The open-source tool provides easy and highly interactive web access to enrichment analysis with the ChEBI ontology tool and is additionally available as a standalone library.

Electronic supplementary material

The online version of this article (doi:10.1186/s12859-015-0486-3) contains supplementary material, which is available to authorized users.     

Cellular reprogramming: a novel tool for investigating autism spectrum disorders

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impairment in reciprocal social interaction and communication, as well as the manifestation of stereotyped behaviors. Despite much effort, ASDs are not yet fully understood. Advanced genetics and genomics technologies have recently identified novel ASD genes, and approaches using genetically engineered murine models or postmortem human brain have facilitated understanding ASD. Reprogramming somatic cells into induced pluripotent stem cells (iPSCs) provides unprecedented opportunities in generating human disease models. Here, we present an overview of applying iPSCs in developing cellular models for understanding ASD. We also discuss future perspectives in the use of iPSCs as a source of cell therapy and as a screening platform for identifying small molecules with efficacy for alleviating ASD.     

The carnegie protein trap library: a versatile tool for Drosophila developmental studies

Metazoan physiology depends on intricate patterns of gene expression that remain poorly known. Using transposon mutagenesis in Drosophila, we constructed a library of 7404 protein trap and enhancer trap lines, the Carnegie collection, to facilitate gene expression mapping at single-cell resolution. By sequencing the genomic insertion sites, determining splicing patterns downstream of the enhanced green fluorescent protein (EGFP) exon, and analyzing expression patterns in the ovary and salivary gland, we found that 600-900 different genes are trapped in our collection. A core set of 244 lines trapped different identifiable protein isoforms, while insertions likely to act as GFP-enhancer traps were found in 256 additional genes. At least 8 novel genes were also identified. Our results demonstrate that the Carnegie collection will be useful as a discovery tool in diverse areas of cell and developmental biology and suggest new strategies for greatly increasing the coverage of the Drosophila proteome with protein trap insertions.     

MedlineR: an open source library in R for Medline literature data mining

SUMMARY: We describe an open source library written in the R programming language for Medline literature data mining. This MedlineR library includes programs to query Medline through the NCBI PubMed database; to construct the co-occurrence matrix; and to visualize the network topology of query terms. The open source nature of this library allows users to extend it freely in the statistical programming language of R. To demonstrate its utility, we have built an application to analyze term-association by using only 10 lines of code. We provide MedlineR as a library foundation for bioinformaticians and statisticians to build more sophisticated literature data mining applications. AVAILABILITY: The library is available from http://dbsr.duke.edu/pub/MedlineR.     

The genome editing toolbox: a spectrum of approaches for targeted modification

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Recent Hits Acquired by BLAST (ReHAB): A tool to identify new hits in sequence similarity searches

Background  

Sequence similarity searching is a powerful tool to help develop hypotheses in the quest to assign functional, structural and evolutionary information to DNA and protein sequences. As sequence databases continue to grow exponentially, it becomes increasingly important to repeat searches at frequent intervals, and similarity searches retrieve larger and larger sets of results. New and potentially significant results may be buried in a long list of previously obtained sequence hits from past searches.     

Facilitating open science without sacrificing IP rights: A novel tool for improving replicability of published research

Conditional Access Agreements could improve replicability of research and enhance Open Science without jeopardizing intellectual property rights. Subject Categories: Economics, Law & Politics, Science Policy & Publishing

Replicability is a cornerstone of the scientific enterprise. Validating published scientific findings enhances their credibility and helps to build a self‐correcting cumulative knowledge base. It also increases public trust in science (Wingen et al  ²⁰²⁰). Unfortunately, the scientific community has been facing a considerable problem for at least two decades: the replication crisis (Ioannidis, ²⁰⁰⁵). Scientists in various disciplines have significant difficulties trying to verify published scientific findings (Baker, ²⁰¹⁶). One prominent factor accounting for non‐replicability is diminished access to research materials required for replication (replication materials).

Scientists in various disciplines have significant difficulties trying to verify published scientific findings.

This problem is particularly noticeable in computational studies: research that utilizes computational models, often with an immense amount of data. With the rise of powerful computers, machine learning and big data, computational studies are increasingly used in a variety of disciplines. This trend is evident in biology as well, including in systems biology, genomics, proteomics, and other areas (Markowetz, ²⁰¹⁷). A famous example that demonstrates the importance of computational biology is the Human Genome Project. Developments in computational biology are crucial in advancing promising research prospects in areas such as vaccine antigen design and structural bioinformatics.

The problem of diminished access to replication materials has been reported as a major stumbling block impeding the replicability of computational biology studies.

A scientific paper alone would not typically enable others to replicate the study described therein (Merali, ²⁰¹⁰). Replicating a computational study generally requires access to the code, software documentation, datasets, workflows, and other information regarding the methodology (Easterbrook, ²⁰¹⁴). In most cases, however, authors do not publicly share these elements, which renders such studies impossible to replicate (Merali, ²⁰¹⁰; Stodden et al, ²⁰¹⁸). The problem of diminished access to replication materials has been reported as a major stumbling block impeding the replicability of computational biology studies (Crook et al, ²⁰¹³; Miłkowski et al, ²⁰¹⁸).     

SIRW: A web server for the Simple Indexing and Retrieval System that combines sequence motif searches with keyword searches

SIRW (http://sirw.embl.de/) is a World Wide Web interface to the Simple Indexing and Retrieval System (SIR) that is capable of parsing and indexing various flat file databases. In addition it provides a framework for doing sequence analysis (e.g. motif pattern searches) for selected biological sequences through keyword search. SIRW is an ideal tool for the bioinformatics community for searching as well as analyzing biological sequences of interest.     

Sortase-mediated protein ligation: an emerging biotechnology tool for protein modification and immobilisation

Sortases are transpeptidases produced by Gram-positive bacteria to anchor cell surface proteins covalently to the cell wall. The Staphylococcus aureus sortase A (SrtA) cleaves a short C-terminal recognition motif (LPXTG) on the target protein followed by the formation of an amide bond with the pentaglycine cross-bridge in the cell wall. Over recent years, several researchers have exploited this specific reaction for a range of biotechnology applications, including the incorporation of non-native peptides and non-peptidic molecules into proteins, the generation of nucleic acid–peptide conjugates and neoglycoconjugates, protein circularisation, and labelling of cell surface proteins on living cells.     

EpiFire: An open source C++ library and application for contact network epidemiology

ABSTRACT: BACKGROUND: Contact network models have become increasingly common in epidemiology, but we lack a flexible programming framework for the generation and analysis of epidemiological contact networks and for the simulation of disease transmission through such networks. RESULTS: Here we present EpiFire, an applications programming interface and graphical user interface implemented in C++, which includes a fast and efficient library for generating, analyzing and manipulating networks. Network-based percolation and chain-binomial simulations of susceptible-infected-recovered disease transmission, as well as traditional non-network mass-action simulations, can be performed using EpiFire. CONCLUSIONS: EpiFire provides an open-source programming interface for the rapid development of network models with a focus in contact network epidemiology. EpiFire also provides a point-and-click interface for generating networks, conducting epidemic simulations, and creating figures. This interface is particularly useful as a pedagogical tool.     

Visualize: a free and open source multifunction tool for proteomics data analysis

A major challenge in the field of high-throughput proteomics is the conversion of the large volume of experimental data that is generated into biological knowledge. Typically, proteomics experiments involve the combination and comparison of multiple data sets and the analysis and annotation of these combined results. Although there are some commercial applications that provide some of these functions, there is a need for a free, open source, multifunction tool for advanced proteomics data analysis. We have developed the Visualize program that provides users with the abilities to visualize, analyze, and annotate proteomics data; combine data from multiple runs, and quantitate differences between individual runs and combined data sets. Visualize is licensed under GNU GPL and can be downloaded from http://proteomics.mcw.edu/visualize. It is available as compiled client-based executable files for both Windows and Mac OS X platforms as well as PERL source code.     

GeneCite: a stand-alone open source tool for high-throughput literature and pathway mining

Systematic extraction of relevant biological facts from available massive scientific knowledge source is emerging as a significant task for the science community. Its success depends on several key factors, including the precision of a given search, the time of its accomplishment, and the communicative prowess of the mined information to the users. GeneCite - a stand-alone Java-based high-throughput data mining tool - is designed to carry out these tasks for several important knowledge sources simultaneously, allowing the users to integrate the results and interpret biological significance in a time-efficient manner. GeneCite provides an integrated high-throughput search platform serving as an information retrieval (IR) tool for probing online literature database (PubMed) and the sequence-tagged sites' database (UniSTS), respectively. It also operates as a data retrieval (DR) tool to mine an archive of biological pathways integrated into the software itself. Furthermore, GeneCite supports a retrieved data management system (DMS) showcasing the final output in a spread-sheet format. Each cell of the output file holds a real-time connection (hyperlink) to the given online archive reachable at the users' convenience. The software is free and currently available online www.bioinformatics.org; www.wrair.army.mil/Resources.     

A large-insert porcine library with sevenfold genome coverage: a tool for positional cloning of candidate genes for major quantitative traits

A porcine genomic bacterial artificial chromosome (BAC) library was constructed by cloning partial EcoRI-digested high-molecular-weight DNA from a Korean native boar into the EcoRI site of the pBACe3.6 vector. The library consists of about 165,000 clones with an average insert size of 125 kb, representing about seven genome equivalents of coverage. About 130,000 clones (corresponding to fivefold genome coverage) were arrayed in 14 superpools which were organized as four dimensional pools. The library was further characterized by PCR screening of 38 microsatellite probes. An average of 4.84 positive clones were selected per marker. This indicates that the library is unbiased and will be useful for initiating fine scale physical mapping of major QTL in pigs. The library is being used to isolate specific clones by screening with type I and type II marker clones located in the QTL region affecting intramuscular fat content on SSC6.     

A tool and an instrument modification to facilitate aortic flow probe placement

A tool was designed and fabricated to simplify the procedure of placing a flow probe around the aortic root in acute animal experiments. The tool was made from a section of silicone rubber tubing which was flattened and tapered at one end. The flow probe was inserted into the open end of the tool, and the tapered end was drawn under the aorta, thus pulling the probe into position. Grooves were also ground into the probe body to ease the installation of the slot cover. During the 2 years that the tool and modified probes were used, they saved time and eliminated rupture of vessels as complications of aortic root flow probe placement.