PATMAT: a searching and extraction program for sequence, pattern and block queries and databases

A program has been developed that provides molecular biologistswith multiple tools for searching databases, yet uses a verysimple interface. PATMATcan use protein or (translated) DNAsequences, patterns or blocks of aligned proteins as queriesof databases consisting of amino acid or nucleotide sequences,patterns or blocks. The ability to search databases of blocksby ‘on-the-fly’ conversion to scoring matrices providesa new tool for detection and evaluation of distant relationships.PATMAT uses a pull-down, menu-driven interface to carry outits multiple searching, extraction and viewing functions. Eachquery or database type is recognized, reported, and the appropriatesearch carried out, with matches and alignments reported inwindows as they occur. Any of the high scoring matches can beexported to a file, viewed and recalled as a query using onlya few keystrokes or mouse selections. Searches of multiple databasefiles are carried out by user selection within a window. PATMATruns under DOS; the searching engine also runs under UNIX.     

Automated protein sequence pattern handling and PROSITE searching

The protein sequence searching program Scrutineer has been modifiedto search for targets from a file. We are distributing a reformattedfile of PROSITES which can be read by Scrutineer. In addition,Scrutineer still accepts targets typed in interactively butcan now write them out in the format required as input. Sincethe input format is the same as the output format, target managementand re-use is simple.     

Spreadsheet-based program for alignment of overlapping DNA sequences.

Molecular biology laboratories frequently face the challenge of aligning small overlapping DNA sequences derived from a long DNA segment. Here, we present a short program that can be used to adapt Excel spreadsheets as a tool for aligning DNA sequences, regardless of their orientation. The program runs on any Windows or Macintosh operating system computer with Excel 97 or Excel 98. The program is available for use as an Excel file, which can be downloaded from the BioTechniques Web site. Upon execution, the program opens a specially designed customized workbook and is capable of identifying overlapping regions between two sequence fragments and displaying the sequence alignment. It also performs a number of specialized functions such as recognition of restriction enzyme cutting sites and CpG island mapping without costly specialized software.     

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/     

JDotter: a Java interface to multiple dotplots generated by dotter

Java-Dotter (JDotter) is a platform-independent Java interactive interface for the Linux version of Dotter, a widely used program for generating dotplots of large DNA or protein sequences. JDotter runs as a client-server application and can send new sequences to the Dotter program for alignment as well as rapidly access a repository of preprocessed dotplots. JDotter also interfaces with a sequence database or file system to display supplementary feature data. Thus, JDotter greatly simplifies access to dotplot data in laboratories that deal with large numbers of genomes and have a multi-platform organization. AVAILABILITY: Currently, JDotter is used via Java Web Start by the Poxvirus Bioinformatics Resource for examining dotplots of complete poxvirus genomes; http://athena.bioc.uvic.ca/pbr/jdotter/. The software is available for download from the same location. SUPPLEMENTARY INFORMATION: Installation instructions, the User's Manual, screenshots and examples are available at the JDotter home page http://athena.bioc.uvic.ca/pbr/jdotter/. The software and source code is free for non-commercial applications.     

SPLICE, a computer program for automated extraction of information from GenBank sequence entries

SPLICE, a software tool for the extraction of sequences fromfiles in GenBank tape format, has been developed. The programcan analyze the features table in this format and use any ofthe information provided to write the corresponding sequencesinto a standard sequence file format suitable for use with sequenceanalysis programs. Sequences that are present as several subsequentfragments in a single GenBank file, such as those encoding apeptide, can be spliced together by the program. Further, sequencesthat are present in more than one Genbank file, such as an exonwhich spans several different files, can also be spliced intoone sequence. SPLICE runs under the MS/DOS and Unix operatingsystems, can be called as a sub-process by other programs andcan process batches of files. Received on December 26, 1989; accepted on May 30, 1990     

Gapped BLAST and PSI-BLAST: a new generation of protein database search programs.

The BLAST programs are widely used tools for searching protein and DNA databases for sequence similarities. For protein comparisons, a variety of definitional, algorithmic and statistical refinements described here permits the execution time of the BLAST programs to be decreased substantially while enhancing their sensitivity to weak similarities. A new criterion for triggering the extension of word hits, combined with a new heuristic for generating gapped alignments, yields a gapped BLAST program that runs at approximately three times the speed of the original. In addition, a method is introduced for automatically combining statistically significant alignments produced by BLAST into a position-specific score matrix, and searching the database using this matrix. The resulting Position-Specific Iterated BLAST (PSI-BLAST) program runs at approximately the same speed per iteration as gapped BLAST, but in many cases is much more sensitive to weak but biologically relevant sequence similarities. PSI-BLAST is used to uncover several new and interesting members of the BRCT superfamily.     

A program for the identification of tRNA-like structures in DNA sequence data.

A computer algorithm has been developed which identifies tRNA genes and tRNA-like structures in DNA sequences. The program searches the sequence string for specific base positions that correspond to the invariant and semi-invariant bases found in tRNAs. The tRNA nature of the sequence is confirmed by the presence of complementary base pairing at the tRNA's calculated 5' and 3' ends (which in situ constitutes the amino-acyl stem region). The program achieves greater than 96% accuracy when run against known tRNA sequences in the Genbank database. The program is modular and is readily modified to allow searching either a file or database. The program is written in "C" and operates on a D.E.C. Vax 750. The utility of the algorithm is demonstrated by the identification of a distinctive tRNA structure in an intron of a published bovine hemoglobin gene.     

利用VBA查找核酸数据库DNA保守序列

采用VBA编写了查找核酸数据库保守序列的四个相关程序,“导入DNA序列”程序可以将Fasta格式的DNA序列文本文件存放到Excel Sheetl的A列中,保留每个序列的Gi号,删除多余的注释部分;“整理DNA序列”程序可以将DNA序列Gi号存放到A列中,B列为对应Gi号的完整序列;“DNA随机序列”程序可以产生DNA随机序列;“发现DNA保守序列”程序可以将随机序列与下载的DNA序列比对,查找每一种随机序列的出现频率.以大豆基因组序列为实例,说明了这些程序的应用方法.该程序弥补了流行序列比对软件的不足,为PCR设计引物、分析基因功能以及种质资源鉴定等方面提供新的工具.     

Improved sensitivity of profile searches through the use of sequence weights and gap excision

Position-specific substitution matrices, known as profiles,derived from multiple sequence alignments are currently usedto search sequence databases for distantly related members ofprotein families. The performance of the database searches isenhanced by using (i) a sequence weighting scheme which assignshigher weights to more distantly related sequences based onbranch lengths derived from phylogenetic trees, (ii) exclusionof positions with mainly padding characters at sites of insertionsor deletions and (iii) the BLOSUM62 residue comparison matrix.A natural consequence of these modifications is an improvementin the alignment of new sequences to the profiles. However,the accuracy of the alignments can be further increased by employinga similarity residue comparison matrix. These developments areimplemented in a program called PROFILEWEIGHT which runs onUnix and Vax computers. The only input required by the programis the multiple sequence alignment. The output from PROFILEWEIGHTis a profile designed to be used by existing searching and alignmentprograms. Test results from database searches with four differentfamilies of proteins show the improved sensitivity of the weightedprofiles.     

MITE-Hunter: a program for discovering miniature inverted-repeat transposable elements from genomic sequences

Miniature inverted-repeat transposable elements (MITEs) are a special type of Class 2 non-autonomous transposable element (TE) that are abundant in the non-coding regions of the genes of many plant and animal species. The accurate identification of MITEs has been a challenge for existing programs because they lack coding sequences and, as such, evolve very rapidly. Because of their importance to gene and genome evolution, we developed MITE-Hunter, a program pipeline that can identify MITEs as well as other small Class 2 non-autonomous TEs from genomic DNA data sets. The output of MITE-Hunter is composed of consensus TE sequences grouped into families that can be used as a library file for homology-based TE detection programs such as RepeatMasker. MITE-Hunter was evaluated by searching the rice genomic database and comparing the output with known rice TEs. It discovered most of the previously reported rice MITEs (97.6%), and found sixteen new elements. MITE-Hunter was also compared with two other MITE discovery programs, FINDMITE and MUST. Unlike MITE-Hunter, neither of these programs can search large genomic data sets including whole genome sequences. More importantly, MITE-Hunter is significantly more accurate than either FINDMITE or MUST as the vast majority of their outputs are false-positives.     

Exon discovery by genomic sequence alignment

MOTIVATION: During evolution, functional regions in genomic sequences tend to be more highly conserved than randomly mutating 'junk DNA' so local sequence similarity often indicates biological functionality. This fact can be used to identify functional elements in large eukaryotic DNA sequences by cross-species sequence comparison. In recent years, several gene-prediction methods have been proposed that work by comparing anonymous genomic sequences, for example from human and mouse. The main advantage of these methods is that they are based on simple and generally applicable measures of (local) sequence similarity; unlike standard gene-finding approaches they do not depend on species-specific training data or on the presence of cognate genes in data bases. As all comparative sequence-analysis methods, the new comparative gene-finding approaches critically rely on the quality of the underlying sequence alignments. RESULTS: Herein, we describe a new implementation of the sequence-alignment program DIALIGN that has been developed for alignment of large genomic sequences. We compare our method to the alignment programs PipMaker, WABA and BLAST and we show that local similarities identified by these programs are highly correlated to protein-coding regions. In our test runs, PipMaker was the most sensitive method while DIALIGN was most specific. AVAILABILITY: The program is downloadable from the DIALIGN home page at http://bibiserv.techfak.uni-bielefeld.de/dialign/.     

A fast DNA sequence handling program for Apple II computer in BASIC and 6502 assembler

A fast general purpose DNA handling program has been developedin BASIC and machine language. The program runs on the AppleII plus or on the Apple IIe microcomputer, without additionalhardware except for disk drives and printer. The program allowsfile insertion and editing, translation into protein sequence,reverse translation, search for small strings and restrictionenzyme sites. The homology may be shown either as a comparisonof two sequences or through a matrix on screen. Two additionalfeatures are: (i) drawing restriction site maps on the printer;and (ii) simulating a gel electrophoresis of restriction fragmentsboth on screen and on paper. All the operations are very fast.The more common tasks are carried out almost instantly; onlymore complex routines, like finding homology between large sequencesor searching and sorting all the restriction sites in a longsequence require longer, but still quite acceptable, times (generallyunder 30 s). Received on October 25, 1984; accepted on December 7, 1984     

PREDITOP: A program for antigenicity prediction

A program (PREDITOP) for predicting the location of antigenic regions (or epitopes) on proteins is described. This program and the associated ones are written in Turbo Pascal and run on IBM-PC compatibles. The program contains 22 normalized scales, corresponding to hydrophilicity, accessibility, flexibility, or secondary structure propensities. New scales are easily implemented. An hydrophobic moment procedure has also been implemented in order to determine amphiphilic helices. The program generates a result file where the values represent a particular physicochemical aspect of the studied protein. PREDITOP can display one or several result files by simple graphical superimposition. Curve combinations can be done by the ADDITIO or MULTIPLI routines which create a new result file by adding or multiplying previously calculated files representing several propensities. The program is useful and efficient for identifying potential antigenic regions in a protein with the aim of raising antibodies against synthesized peptides which cross-react with the native protein.     

A new method of global search for functional DNA segments using a fractal representation of nucleotide texts]

New global method for computer prediction of functional sites in nucleotide sequences, based on the fractal representation, is presented. Fractal representation of set of sequences (FRS) provides simple way for generating recognitions matrix of functionally similar sequences and simple estimations of its efficiency for searching homologous regions in new sequences. Other advantages of the method are absence of the necessity of sequences alignment during generating based set and searching new homologous regions and small CPU time. Usage of the method illustrated for searching globin and histone genes, for ALU repeats in human genome and long terminal repeats in virus genome.     

DNA sequence analysis: a procedure to find homologies among many sequences.

SEQCMP, a program that analyzes and searches for homology among multiple nucleic acid sequences, is described. The sequences are compared by the dot matrix method and the consensus sequence is derived by superimposing all the dot matrices on one another. The program is written in MBASIC and runs on IBM-PC microcomputer. It is interactive and can be used by investigators with no computer background or experience.     

Identification of proteins in sequence databases from amino acid composition data.

Having obtained the amino acid composition of a protein, chemists and molecular biologists may wish to identify the protein from this data alone. In general such data will have errors associated with them and the length of the protein may be known only approximately or not at all. In this paper a method is described which enables searching of protein sequence databases for sequences or fragments of sequences which have a composition similar to the one being sought. Such searches are generally quite discriminating as shown by the examples provided. This method has been implemented as part of the computer program Scrutineer and is being freely distributed. It is simple to use.     

核酸顺序的计算机辅助分析系统

本文介绍了一个在微机(IBM PC)上实现的、用于核酸顺序分析的计算机程序系统.该系统由三个层次和18个功能块构成,菜单及人机对话使得用户能较快地掌握和使用它.在编程中,采用了树结构、先进后出栈和稀疏矩阵等数据结构技巧,运用了Bayes法等统计分析方法,Kruskal算法和Floyd算法等一系列图论方法也被得到应用,这个软件系统的推出对于分子生物学研究具有一定的积极作用.     

BLAST 2 Sequences, a new tool for comparing protein and nucleotide sequences

'BLAST 2 Sequences', a new BLAST-based tool for aligning two protein or nucleotide sequences, is described. While the standard BLAST program is widely used to search for homologous sequences in nucleotide and protein databases, one often needs to compare only two sequences that are already known to be homologous, coming from related species or, e.g. different isolates of the same virus. In such cases searching the entire database would be unnecessarily time-consuming. 'BLAST 2 Sequences' utilizes the BLAST algorithm for pairwise DNA-DNA or protein-protein sequence comparison. A World Wide Web version of the program can be used interactively at the NCBI WWW site (http://www.ncbi.nlm.nih.gov/gorf/bl2.++ +html). The resulting alignments are presented in both graphical and text form. The variants of the program for PC (Windows), Mac and several UNIX-based platforms can be downloaded from the NCBI FTP site (ftp://ncbi.nlm.nih.gov).