CompDb databases can be created with the createCompDb() or the
emptyCompDb() functions, the former creating and initializing (filling)
the database with existing data, the latter creating an empty database that
can be subsequently filled with insertCompound() or insertSpectra()
calls.
emptyCompDb() requires only the file name of the database that should be
created as input and returns a CompDb representing the empty database.
createCompDb() creates a SQLite-based CompDb object/database
from a compound resource provided as a data.frame or tbl. Alternatively,
the name(s) of the file(s) from which the annotation should be extracted can
be provided. Supported are SDF files (such as those from the
Human Metabolome Database HMDB) that can be read using the
compound_tbl_sdf() or LipidBlast files (see compound_tbl_lipidblast().
An additional data.frame providing metadata information including the data
source, date, version and organism is mandatory. By default, the function
will define the name of the database based on the provided metadata, but it
is also possible to define this manually with the dbFile parameter.
Optionally MS/MS (MS2) spectra for compounds can be also stored in the
database. Currently only MS/MS spectra from HMDB are supported. These can
be downloaded in XML format from HMDB (http://www.hmdb.ca), loaded with
the msms_spectra_hmdb() or msms_spectra_mona() function and passed to
the function with the msms_spectra argument. See msms_spectra_hmdb() or
msms_spectra_mona() for information on the expected columns and format.
Required columns for the data.frame providing the compound information (
parameter x) are:
"compound_id": the ID of the compound. Can be anintegerorcharacter. Duplicated IDs are supported (for compatibility reasons), but not suggested. No missing values allowed."name": the compound's name."inchi": the InChI of the compound."inchikey": the InChI key."formula": the chemical formula."exactmass": the compound's (exact) mass."synonyms": additional synonyms/aliases for the compound. Should be either a single character or a list of values for each compound.
Any additional columns in the provided data.frame (such as e.g. "smiles"
providing the compound's SMILES) are also supported and will be inserted into
the database table.
See e.g. compound_tbl_sdf() or compound_tbl_lipidblast() for functions
creating such compound tables.
The table containing the MS2 spectra data should have the following format and columns:
"spectrum_id": an arbitrary ID for the spectrum. Has to be aninteger."compound_id": the ID of the compound to which the spectrum can be associated with. This has to be present in thedata.framedefining the compounds."polarity": the polarity (as aninteger,0for negative,1for positive,NAfor not set)."collision_energy": the collision energy."predicted": whether the spectrum was predicted or measured."splash": the SPLASH of the spectrum."instrument_type": the instrument type."instrument": the name of the instrument."precursor_mz": the precursor m/z (as anumeric)."mz": the m/z values."intensity": the intensity values.
Only for columns "spectrum_id", "compound_id", "mz" and "intensity"
a value has to be provided in each row of the data.frame. The others are
optional. Note that the data.frame can be either in the format as in the
example below (i.e. each row being one spectrum and columns "mz" and
"intensity" being of type list each element being the m/z or intensity
values of one spectrum) or in a full form, in which each row represents
one peak and all columns except "mz" and "intensity" containing
redundant information of each spectrum (hence columns "mz" and
"intensity" being of type numeric).
The metadata data.frame is supposed to have two columns named "name" and
"value" providing the following minimal information as key-value pairs
(see make_metadata for a utility function to create such a data.frame):
"source": the source from which the data was retrieved (e.g."HMDB")."url": the url from which the original data was retrieved."source_version": the version from the original data source (e.g."v4")."source_date": the date when the original data source was generated."organism": the organism. Should be in the form"Hsapiens"or"Mmusculus".
createCompDbPackage creates an R data package with the data from a
CompDb object.
make_metadata() helps generating a metadata data.frame in
the correct format expected by the createCompDb function. The function
returns a data.frame.
Usage
createCompDb(x, metadata, msms_spectra, path = ".", dbFile = character())
createCompDbPackage(
x,
version,
maintainer,
author,
path = ".",
license = "Artistic-2.0"
)
make_metadata(
source = character(),
url = character(),
source_version = character(),
source_date = character(),
organism = NA_character_
)
emptyCompDb(dbFile = character())Arguments
- x
For
createCompDb():data.frameortblwith the compound annotations orcharacterwith the file name(s) from which the compound annotations should be retrieved. See description for details.- metadata
For
createCompDb():data.framewith metadata information. See description for details.- msms_spectra
For
createCompDb():data.framewith MS/MS spectrum data. Seemsms_spectra_hmdb()for the expected format and a function to import such data from spectrum xml files from HMDB.- path
character(1)with the path to the directory where the database file or package folder should be written. Defaults to the current directory.- dbFile
character(1)to optionally provide the name of the SQLite database file. If not provided (the default) the database name is defined using information from the providedmetadata.- version
For
createCompDbPackage():character(1)with the version of the package (ideally in the format"x.y.z").- maintainer
For
createCompDbPackage():character(1)with the name and email address of the package maintainer (in the form"First Last <first.last@provider.com>".For
createCompDbPackage():character(1)with the name of the package author.- license
For
createCompDbPackage():character(1)with the license of the package respectively the originating provider.- source
For
make_metadata():character(1)with the name of the resource that provided the compound annotation.- url
For
make_metadata():character(1)with the url to the original resource.- source_version
For
make_metadata():character(1)with the version of the original resource providing the annotation.- source_date
For
make_metadata():character(1)with the date of the resource's release.- organism
For
make_metadata():character(1)with the name of the organism. This should be in the format"Hsapiens"for human,"Mmusculus"for mouse etc. Leave toNAif not applicable.
Details
Metadata information is also used to create the file name for the database
file. The name starts with "CompDb", followed by the organism, the
data source and its version. A compound database file for HMDB version 4
with human metabolites will thus be named: "CompDb.Hsapiens.HMDB.v4".
A single CompDb database is created from multiple SDF files (e.g. for
PubChem) if all the file names are provided with parameter x. Parallel
processing is currently not enabled because SQLite does not support it yet
natively.
See also
compound_tbl_sdf() and compound_tbl_lipidblast() for functions
to extract compound annotations from files in SDF format, or files from
LipidBlast.
import_mona_sdf() to import both the compound and spectrum data from a
SDF file from MoNa (Massbank of North America) in one call.
msms_spectra_hmdb() and msms_spectra_mona() for functions to import
MS/MS spectrum data from xml files from HMDB or an SDF file from MoNa.
CompDb() for how to use a compound database.
Examples
## Read compounds for a HMDB subset
fl <- system.file("sdf/HMDB_sub.sdf.gz", package = "CompoundDb")
cmps <- compound_tbl_sdf(fl)
## Create a metadata data.frame for the compounds.
metad <- data.frame(name = c("source", "url", "source_version",
"source_date", "organism"), value = c("HMDB", "http://www.hmdb.ca",
"v4", "2017-08-27", "Hsapiens"))
## Alternatively use the make_metadata helper function
metad <- make_metadata(source = "HMDB", source_version = "v4",
source_date = "2017-08", organism = "Hsapiens",
url = "http://www.hmdb.ca")
## Create a SQLite database in the temporary folder
db_f <- createCompDb(cmps, metadata = metad, path = tempdir())
## The database can be loaded and accessed with a CompDb object
db <- CompDb(db_f)
db
#> class: CompDb
#> data source: HMDB
#> version: v4
#> organism: Hsapiens
#> compound count: 9
## Create a database for HMDB that includes also MS/MS spectrum data
metad2 <- make_metadata(source = "HMDB_with_spectra", source_version = "v4",
source_date = "2017-08", organism = "Hsapiens",
url = "http://www.hmdb.ca")
## Import spectrum information from selected MS/MS xml files from HMDB
## that are provided in the package
xml_path <- system.file("xml", package = "CompoundDb")
spctra <- msms_spectra_hmdb(xml_path)
#> Going to process 4 xml files.
#> Postprocessing data ...
#> OK
## Create a SQLite database in the temporary folder
db_f2 <- createCompDb(cmps, metadata = metad2, msms_spectra = spctra,
path = tempdir())
## The database can be loaded and accessed with a CompDb object
db2 <- CompDb(db_f2)
db2
#> class: CompDb
#> data source: HMDB_with_spectra
#> version: v4
#> organism: Hsapiens
#> compound count: 9
#> MS/MS spectra count: 4
## Does the database contain MS/MS spectrum data?
hasMsMsSpectra(db2)
#> [1] TRUE
## Create a database for a ChEBI subset providing the file name of the
## corresponding SDF file
metad <- make_metadata(source = "ChEBI_sub", source_version = "2",
source_date = NA, organism = "Hsapiens", url = "www.ebi.ac.uk/chebi")
db_f <- createCompDb(system.file("sdf/ChEBI_sub.sdf.gz",
package = "CompoundDb"), metadata = metad, path = tempdir())
#> Import data from ChEBI_sub.sdf.gz ...
#> OK
db <- CompDb(db_f)
db
#> class: CompDb
#> data source: ChEBI_sub
#> version: 2
#> organism: Hsapiens
#> compound count: 6
compounds(db)
#> name
#> 1 (-)-epicatechin
#> 2 (1S,4R)-fenchone
#> 3 1-alkyl-2-acylglycerol
#> 4 16alpha-hydroxyestrone
#> 5 2,6-dichlorobenzonitrile
#> 6 2-hydroxybutyric acid
#> inchi
#> 1 InChI=1S/C15H14O6/c16-8-4-11(18)9-6-13(20)15(21-14(9)5-8)7-1-2-10(17)12(19)3-7/h1-5,13,15-20H,6H2/t13-,15-/m1/s1
#> 2 InChI=1S/C10H16O/c1-9(2)7-4-5-10(3,6-7)8(9)11/h7H,4-6H2,1-3H3/t7-,10+/m1/s1
#> 3 <NA>
#> 4 InChI=1S/C18H22O3/c1-18-7-6-13-12-5-3-11(19)8-10(12)2-4-14(13)15(18)9-16(20)17(18)21/h3,5,8,13-16,19-20H,2,4,6-7,9H2,1H3/t13-,14-,15+,16-,18+/m1/s1
#> 5 InChI=1S/C7H3Cl2N/c8-6-2-1-3-7(9)5(6)4-10/h1-3H
#> 6 InChI=1S/C4H8O3/c1-2-3(5)4(6)7/h3,5H,2H2,1H3,(H,6,7)
#> inchikey formula exactmass
#> 1 PFTAWBLQPZVEMU-UKRRQHHQSA-N C15H14O6 290.079
#> 2 LHXDLQBQYFFVNW-XCBNKYQSSA-N C10H16O 152.120
#> 3 <NA> C4H6O4R2 118.027
#> 4 WPOCIZJTELRQMF-QFXBJFAPSA-N C18H22O3 286.157
#> 5 YOYAIZYFCNQIRF-UHFFFAOYSA-N C7H3Cl2N 170.964
#> 6 AFENDNXGAFYKQO-UHFFFAOYSA-N C4H8O3 104.047
#> smiles
#> 1 [H][C@@]1(Oc2cc(O)cc(O)c2C[C@H]1O)c1ccc(O)c(O)c1
#> 2 CC1(C)[C@@H]2CC[C@@](C)(C2)C1=O
#> 3 OCC(CO[*])OC([*])=O
#> 4 [H][C@]12CC[C@]3(C)C(=O)[C@H](O)C[C@@]3([H])[C@]1([H])CCc1cc(O)ccc21
#> 5 Clc1cccc(Cl)c1C#N
#> 6 CCC(O)C(O)=O
## connect to the database and query it's tables using RSQlite
library(RSQLite)
con <- dbConnect(dbDriver("SQLite"), db_f)
dbGetQuery(con, "select * from metadata")
#> name value
#> 1 source ChEBI_sub
#> 2 url www.ebi.ac.uk/chebi
#> 3 source_version 2
#> 4 source_date <NA>
#> 5 organism Hsapiens
#> 6 db_creation_date Fri Sep 27 12:10:04 2024
#> 7 supporting_package CompoundDb
#> 8 supporting_object CompDb
dbGetQuery(con, "select * from ms_compound")
#> compound_id name
#> 1 CHEBI:90 (-)-epicatechin
#> 2 CHEBI:165 (1S,4R)-fenchone
#> 3 CHEBI:598 1-alkyl-2-acylglycerol
#> 4 CHEBI:776 16alpha-hydroxyestrone
#> 5 CHEBI:943 2,6-dichlorobenzonitrile
#> 6 CHEBI:1148 2-hydroxybutyric acid
#> inchi
#> 1 InChI=1S/C15H14O6/c16-8-4-11(18)9-6-13(20)15(21-14(9)5-8)7-1-2-10(17)12(19)3-7/h1-5,13,15-20H,6H2/t13-,15-/m1/s1
#> 2 InChI=1S/C10H16O/c1-9(2)7-4-5-10(3,6-7)8(9)11/h7H,4-6H2,1-3H3/t7-,10+/m1/s1
#> 3 <NA>
#> 4 InChI=1S/C18H22O3/c1-18-7-6-13-12-5-3-11(19)8-10(12)2-4-14(13)15(18)9-16(20)17(18)21/h3,5,8,13-16,19-20H,2,4,6-7,9H2,1H3/t13-,14-,15+,16-,18+/m1/s1
#> 5 InChI=1S/C7H3Cl2N/c8-6-2-1-3-7(9)5(6)4-10/h1-3H
#> 6 InChI=1S/C4H8O3/c1-2-3(5)4(6)7/h3,5H,2H2,1H3,(H,6,7)
#> inchikey formula exactmass
#> 1 PFTAWBLQPZVEMU-UKRRQHHQSA-N C15H14O6 290.079
#> 2 LHXDLQBQYFFVNW-XCBNKYQSSA-N C10H16O 152.120
#> 3 <NA> C4H6O4R2 118.027
#> 4 WPOCIZJTELRQMF-QFXBJFAPSA-N C18H22O3 286.157
#> 5 YOYAIZYFCNQIRF-UHFFFAOYSA-N C7H3Cl2N 170.964
#> 6 AFENDNXGAFYKQO-UHFFFAOYSA-N C4H8O3 104.047
#> smiles
#> 1 [H][C@@]1(Oc2cc(O)cc(O)c2C[C@H]1O)c1ccc(O)c(O)c1
#> 2 CC1(C)[C@@H]2CC[C@@](C)(C2)C1=O
#> 3 OCC(CO[*])OC([*])=O
#> 4 [H][C@]12CC[C@]3(C)C(=O)[C@H](O)C[C@@]3([H])[C@]1([H])CCc1cc(O)ccc21
#> 5 Clc1cccc(Cl)c1C#N
#> 6 CCC(O)C(O)=O
## To create a CompDb R-package we could simply use the
## createCompDbPackage function on the SQLite database file name.