AnnotationBust: Breaks up genbank sequences into their annotated components...

In AnnotationBustR: Extract Subsequences from GenBank Annotations

Breaks up genbank sequences into their annotated components based on a set of search terms and writes each subsequence of interest to a FASTA for each accession number supplied.

Description

Breaks up genbank sequences into their annotated components based on a set of search terms and writes each subsequence of interest to a FASTA for each accession number supplied.

Usage

AnnotationBust(
  Accessions,
  Terms,
  Duplicates = NULL,
  DuplicateInstances = NULL,
  TranslateSeqs = "None",
  DuplicateSpecies = FALSE,
  Prefix = NULL,
  TidyAccessions = TRUE,
  Reference = TRUE,
  Verbose = TRUE
)

Arguments

Accessions	A vector of GenBank accession numbers.
Terms	A data frame of search terms. Search terms for animal mitogenomes, nuclear rRNA, chloroplast genomes, and plant mitogenomes are pre-made and can be loaded using the data() function. Additional terms can be added using the MergeSearchTerms function or a user supplied data frame may be provided.
Duplicates	A vector of the features which occur more than once in the sequence and for which the extraction of multiple copies is desired. Default is NULL. In the case more than one copy exists when set to NULL, only the first instance will be extracted.
DuplicateInstances	A numeric vector the length of Duplicates of the number of duplicates for each duplicated feature you wish to extract. Only needs to be used if Duplicates are provided.Default is NULL (i.e. no duplicates).
TranslateSeqs	Should coding sequences (cds) be translated to the corresponding peptide sequence? Options include, Only, None, or Both. Both returns both the DNA sequence and the corresponding peptide sequence. Default is FALSE.
DuplicateSpecies	Logical. As to whether there are duplicate individuals per species. If TRUE, adds the accession number to the fasta header when writing sequences to file.
Prefix	Character. If a prefix is specified, all output FASTA files written will begin with the prefix followed by an underscore. Default is NULL (i.e. no prefix).
TidyAccessions	Logical. Should the accession table have a single row per species? If numerous accessions for a species occur, they will be separated by a comma in the accession table. Default=TRUE.
Reference	Logical. Should reference information be captured and added as a column to the accession table? Default is TRUE.
Verbose	Logical. Should progress be printed to the screen. The current accession and species name will be printed to the screen.

Details

The AnnotationBust function takes a vector of accession numbers and a data frame of search terms and extracts subsequences from genomes or concatenated sequences. This function connects directly to the NCBI database and requires a steady internet connection. The function writes files in the FASTA format to the current working directory and returns an accession table. Files append, so use different prefixes between runs, otherwise they will be added to current files in the working directory with the same name.

AnnotationBustR comes with pre-made search terms for metazoan mitogenomes, plant mitogenomes, chloroplast genomes, and rDNA that can be loaded using data(mtDNAterms), data(mtDNAtermsPlants), data(cpDNAterms), and data(rDNAterms) respectively. Search terms can be completely made by the user if they follow a similar format with three columns. The first, Feature, should contain the name of the features as the user wishes it be displayed in their files as it is used to name the files and create the accession table. We recommend following a similar naming convention to what we currently have in the pre-made data frames to ensure that files are named properly, characters like "-" or ".", and names starting with numbers should be avoided as it can cause errors with R. The second column, Type, contains the type of subsequence it is (eg. CDS, exon, intron, rRNA, tRNA, misc_RNA, misc_feature, D_Loop). The last column, Name, consists of a possible synonym for the feature of interest as it might appear in an annotation. For numerous synonyms for the same locus, one should have each synonym as its own row. An additional fourth column is needed for extracting introns/exons. This column, called IntronExonNumber should contain the number of the desired intron or exon to extract. If extracting both introns/exons and non-intron/exon sequences the fourth column should be NA for non-intron/exon sequence types. See the examples below and the vignette for detailed examples on extracting intron and exons.

In the event that an accession is not found on NCBI, the message “Accession # not found on NBI”.

For a more detailed walk-through on using AnnotationBust you can access the vignette with vignette("AnnotationBustR).

Value

Writes a fasta file(s) to the current working directory selected for each unique subsequence of interest in Terms containing all the accession numbers the subsequence was found in.

An accesion table of class data.frame.

Author(s)

Samuel R. Borstein, Brian C. O'Meara

References

Borstein SR, and O’Meara BC. 2018. AnnotationBustR: an R package to extract subsequences from GenBank annotations. PeerJ 6:e5179. 10.7717/peerj.5179.

Examples

ncbi.accessions <- c("FJ706295","FJ706343","FJ706292")
data(rDNAterms)#load rDNA search terms from AnnotationBustR
my.sequences <- AnnotationBust(Accessions = ncbi.accessions, rDNAterms, DuplicateSpecies=TRUE, 
Prefix="Example1", Reference = TRUE)
my.sequences

###Example With matK CDS and addint introns/exons for trnK###
#Subset out matK from cpDNAterms
cds.terms <- subset(cpDNAterms,cpDNAterms$Feature=="matK")
#Create a vecotr of NA so we can merge with the search terms for introns and exons
cds.terms <- cbind(cds.terms,(rep(NA,length(cds.terms$Feature))))
colnames(cds.terms)[4] <- "IntronExonNumber"

#Prepare a search term table for the intron and exons to remove
#We can start with the cpDNAterms for trnK
IntronExon.terms<-subset(cpDNAterms,cpDNAterms$Feature=="trnK")

#As we want to go for two exons, we will want the synonyms repeated as we are doing and intron
#and an exon
IntronExon.terms<-rbind(IntronExon.terms,IntronExon.terms)#duplicate the terms

#rep the sequence type we want to extract
IntronExon.terms$Type <- rep(c("intron","intron","exon","exon"))
IntronExon.terms$Feature <- rep(c("trnK_Intron","trnK_Exon2"),each=2)
IntronExon.terms <- cbind(IntronExon.terms,rep(c(1,1,2,2)))#Add intron/exon number info

#change column name for number info for IntronExon name
colnames(IntronExon.terms)[4] <- "IntronExonNumber"

#We can then merge everything together with MergeSearchTerms terms
IntronExonExampleTerms <- MergeSearchTerms(IntronExon.terms,cds.terms)

#Run AnnotationBust
IntronExon.example <- AnnotationBust(Accessions=c("KX687911.1", "KX687910.1"),
Terms=IntronExonExampleTerms, Prefix="DemoIntronExon")

AnnotationBustR documentation built on Sept. 1, 2026, 1:09 a.m.