The goal of this exercise is to make you familiar with how to download data from Google Sheets and to briefly review some key concepts R functions and coding concepts.

We’ll do the following things

DOWNLOAD ALL NECESSARY PACKAGES

Packages

## Google sheets download package
# comment this out when you are done
# install.packages("googlesheets4")
library(googlesheets4)

# comp bio packages
library(seqinr)
library(rentrez)
library(compbio4all)
library(Biostrings)
## Loading required package: BiocGenerics
## Loading required package: parallel
## 
## Attaching package: 'BiocGenerics'
## The following objects are masked from 'package:parallel':
## 
##     clusterApply, clusterApplyLB, clusterCall, clusterEvalQ,
##     clusterExport, clusterMap, parApply, parCapply, parLapply,
##     parLapplyLB, parRapply, parSapply, parSapplyLB
## The following objects are masked from 'package:stats':
## 
##     IQR, mad, sd, var, xtabs
## The following objects are masked from 'package:base':
## 
##     anyDuplicated, append, as.data.frame, basename, cbind, colnames,
##     dirname, do.call, duplicated, eval, evalq, Filter, Find, get, grep,
##     grepl, intersect, is.unsorted, lapply, Map, mapply, match, mget,
##     order, paste, pmax, pmax.int, pmin, pmin.int, Position, rank,
##     rbind, Reduce, rownames, sapply, setdiff, sort, table, tapply,
##     union, unique, unsplit, which.max, which.min
## Loading required package: S4Vectors
## Loading required package: stats4
## 
## Attaching package: 'S4Vectors'
## The following objects are masked from 'package:base':
## 
##     expand.grid, I, unname
## Loading required package: IRanges
## Loading required package: XVector
## Loading required package: GenomeInfoDb
## 
## Attaching package: 'Biostrings'
## The following object is masked from 'package:seqinr':
## 
##     translate
## The following object is masked from 'package:base':
## 
##     strsplit

Download data

FIRST, WE NEED TO GIVE R A LINK TO THE GOOGLE SHEET THAT WE WANT TO PULL INFORMATION FROM

spreadsheet_sp <- "https://docs.google.com/spreadsheets/d/1spC_ZA3_cVuvU3e_Jfcj2nEIfzp-vaP7SA5f-qwQ1pg/edit?usp=sharing" 

SECOND, WE NEED TO HAVE FREE ACCESS TO THE GOOGLE SHEET

# be sure to run this!
googlesheets4::gs4_deauth()   # <====== MUST RUN THIS

Third, we download our data.

NOTE!: sometimes Google Sheets or the function gets cranky and throws this error:

“Error in curl::curl_fetch_memory(url, handle = handle) : Error in the HTTP2 framing layer”

If that happens, just re-run the code.

# I include this again in case you missed is the first time : )
googlesheets4::gs4_deauth()  

# download
## NOTE: if you get an error, just run the code again
refseq_column <- read_sheet(ss = spreadsheet_sp, # the url
           sheet = "RefSeq_prot",                # the name of the worksheet
           range = "selenoprot!H1:H364",
           col_names = TRUE,
           na = "",                              # fill in empty spaces "" w/NA
           trim_ws = TRUE)
## ✓ Reading from "human_gene_table".
## ✓ Range ''selenoprot'!H1:H364'.
## NOTE: if you get an error, just run the code again

# for reasons we won't get into I'm going to do this
protein_refseq <- refseq_column$RefSeq_prot

THIS SHOWS US THE FIRST 10 PROTEIN ACCESSION NUMBERS

protein_refseq[1:10]
##  [1] "NP_000783.2"    "NP_998758.1"    "NP_001034804.1" "NP_001034805.1"
##  [5] "NP_001311245.1" NA               NA               "NP_054644.1"   
##  [9] "NP_001353425.1" "NP_000784.3"

WE CAN TAKE THE NAME COLUMN INFORMATION AND TURN IT INTO A VECTOR OF ALL STUDENT NAMES

# download
## NOTE: if you get an error, just run the code again
gene_name_column <- read_sheet(ss = spreadsheet_sp, # the url
           sheet = "gene",                # the name of the worksheet
           range = "selenoprot!A1:A364",
           col_names = TRUE,
           na = "",                              # fill in empty spaces "" w/NA
           trim_ws = TRUE)
## ✓ Reading from "human_gene_table".
## ✓ Range ''selenoprot'!A1:A364'.
## NOTE: if you get an error, just run the code again

# for reasons we won't get into I'm going to do this
gene <- gene_name_column$gene

PROTEIN ACCESSION NUMBER INFORMATION

THIS TELLS US ALL INFORMATION ABOUT OUR PROTEIN ACCESSION VECTOR

is(protein_refseq)
##  [1] "character"               "vector"                 
##  [3] "data.frameRowLabels"     "SuperClassMethod"       
##  [5] "character_OR_connection" "character_OR_NULL"      
##  [7] "atomic"                  "EnumerationValue"       
##  [9] "vector_OR_Vector"        "vector_OR_factor"
class(protein_refseq)
## [1] "character"
length(protein_refseq)
## [1] 363
protein_refseq[1:10]
##  [1] "NP_000783.2"    "NP_998758.1"    "NP_001034804.1" "NP_001034805.1"
##  [5] "NP_001311245.1" NA               NA               "NP_054644.1"   
##  [9] "NP_001353425.1" "NP_000784.3"

THIS FUNCTION WILL SHOW WHETHER EACH ITEM HAS NA IN IT

is.na(protein_refseq)
##   [1] FALSE FALSE FALSE FALSE FALSE  TRUE  TRUE FALSE FALSE FALSE FALSE  TRUE
##  [13]  TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE  TRUE  TRUE  TRUE FALSE
##  [25] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE  TRUE  TRUE FALSE FALSE
##  [37] FALSE  TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
##  [49] FALSE FALSE FALSE  TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
##  [61] FALSE FALSE FALSE FALSE FALSE FALSE FALSE  TRUE FALSE FALSE FALSE FALSE
##  [73]  TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE  TRUE
##  [85] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
##  [97] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [109] FALSE  TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [121]  TRUE FALSE  TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE  TRUE FALSE
## [133] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [145] FALSE FALSE FALSE FALSE  TRUE FALSE FALSE FALSE FALSE FALSE FALSE  TRUE
## [157] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [169] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [181] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [193] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE  TRUE  TRUE FALSE
## [205] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [217] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [229] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [241] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE  TRUE  TRUE
## [253] FALSE FALSE FALSE  TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [265] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [277] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE  TRUE FALSE
## [289]  TRUE  TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [301] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [313] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [325] FALSE FALSE FALSE FALSE FALSE FALSE  TRUE FALSE FALSE FALSE FALSE FALSE
## [337] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [349] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE
## [361] FALSE FALSE FALSE

THE TABLE MAKES THE INFORMATION MUCH MORE ACCESSIBLE AND TELLS HOW MANY OF THE ITEMS ARE TRUE AND HOW MANY ARE FALSE

table(is.na(protein_refseq))
## 
## FALSE  TRUE 
##   334    29

WHAT’S THIS DOING?

# WE ARE ASSIGNING THE NA VECTOR TO A VARIABLE TEMP
temp <- is.na(protein_refseq)

# ALL OF THE TRUE VALUES WILL PRINT OUT SHOWING THE 29 NAS
protein_refseq[temp]
##  [1] NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA
## [26] NA NA NA NA
temp2 <- protein_refseq[temp]

# THE LENGTH JUST SHOWS THAT ONCE AGAIN THERE ARE 29 NAS
length(temp2)
## [1] 29

CREATING THE DATAFRAME

WE ARE NOW CREATING A DATAFRAME WITH THE GENE NAME AND PROTEIN ACCESSION NUMBERS

seleno_df <- data.frame(gene = gene,
                        protein_refseq = protein_refseq)

THIS CHUNK WILL SHOW THE LENGTH OF THE COMPARED VECTORS AND THE BEGINNING OF THE DATAFRAME

summary(seleno_df)
##      gene           protein_refseq    
##  Length:363         Length:363        
##  Class :character   Class :character  
##  Mode  :character   Mode  :character
head(seleno_df)
##   gene protein_refseq
## 1 DIO1    NP_000783.2
## 2 DIO1    NP_998758.1
## 3 DIO1 NP_001034804.1
## 4 DIO1 NP_001034805.1
## 5 DIO1 NP_001311245.1
## 6 DIO1           <NA>

CLEANING THE PROTEIN ACCESSION DATA

THIS CHUNK IS REMOVING ALL OF THE ROWS THAT HAVE NA IN THEM

# omit NAs
seleno_df_noNA <- na.omit(seleno_df)

# check length- should be shorter
dim(seleno_df)
## [1] 363   2
dim(seleno_df_noNA)
## [1] 334   2

SEPARATING UNIQUE PROTEIN ISOFORMS

The same gene can appear multiple times because multiple isoforms are listed.

head(seleno_df_noNA)
##   gene protein_refseq
## 1 DIO1    NP_000783.2
## 2 DIO1    NP_998758.1
## 3 DIO1 NP_001034804.1
## 4 DIO1 NP_001034805.1
## 5 DIO1 NP_001311245.1
## 8 DIO2    NP_054644.1

THESE FUNCTIONS HELP TO SHOW THE UNIQUE GENES

genes_unique <- unique(seleno_df_noNA$gene)
length(genes_unique)
## [1] 37
genes_unique
##  [1] "DIO1"     "DIO2"     "DIO3"     "GPX1"     "GPX2"     "GPX3"    
##  [7] "GPX4"     "GPX6"     "MSRB1"    "SELENOF"  "SELENOH"  "SELENOI" 
## [13] "SELENOK"  "SELENOM"  "SELENON"  "SELENOO"  "SELENOP"  "SELENOS" 
## [19] "SELENOT"  "SELENOV"  "SELENOW"  "SEPHS2"   "TXNRD1"   "TXNRD2"  
## [25] "TXNRD3"   "SELENOP1" "SELENOP2" "SELENOU"  "SELENOW1" "SELENOW2"
## [31] "SELENOE"  "SELENOJ"  "SELENOL"  "SELENOO1" "SELENOO2" "SELENOT1"
## [37] "SELENOT2"

unique() just gives us the unique elements. A related function, duplicated(), gives us the location of duplicated elements in the vector. FALSE means “not duplicated yet” or “first instance so far”.

i.dups <- duplicated(seleno_df_noNA$gene)

We can remove the duplicates using a form of reverse indexing where the “!” means “not”. (You don’t need to know this for the exam)

seleno_df_noNA[!i.dups, ]
##         gene protein_refseq
## 1       DIO1    NP_000783.2
## 8       DIO2    NP_054644.1
## 14      DIO3    NP_001353.4
## 15      GPX1    NP_000572.2
## 20      GPX2    NP_002074.2
## 24      GPX3    NP_002075.2
## 26      GPX4    NP_002076.2
## 29      GPX6    NP_874360.1
## 30     MSRB1    NP_057416.1
## 31   SELENOF    NP_004252.2
## 35   SELENOH    NP_734467.1
## 37   SELENOI    NP_277040.1
## 39   SELENOK    NP_067060.2
## 40   SELENOM    NP_536355.1
## 41   SELENON    NP_996809.1
## 43   SELENOO    NP_113642.1
## 44   SELENOP    NP_005401.3
## 47   SELENOS    NP_060915.2
## 49   SELENOT    NP_057359.2
## 50   SELENOV    NP_874363.1
## 53   SELENOW    NP_003000.1
## 54    SEPHS2    NP_036380.2
## 55    TXNRD1    NP_877393.1
## 62    TXNRD2    NP_006431.2
## 69    TXNRD3    NP_443115.1
## 232 SELENOP1 NP_001026780.2
## 233 SELENOP2 NP_001335698.1
## 236  SELENOU NP_001180447.1
## 268 SELENOW1 NP_001291715.2
## 269 SELENOW2 NP_001341647.1
## 334  SELENOE NP_001182713.2
## 338  SELENOJ NP_001180398.1
## 340  SELENOL NP_001177311.1
## 343 SELENOO1 NP_001038336.2
## 344 SELENOO2 NP_001335014.1
## 348 SELENOT1    NP_840075.2
## 350 SELENOT2 NP_001091957.2

Make a dataframe of non-duplicated genes

seleno_df_noDups <- seleno_df_noNA[!i.dups, ]
dim(seleno_df_noDups)
## [1] 37  2

RETRIEVING DATA AND COMPARING SEQUENCES

Let’s select 2 random sequences to work with. We’ll use SAMPLE() to select a random index number to get

First, lets make a vector that contains a unique number for each row of data

indices <- 1:nrow(seleno_df_noDups)

This would do the same thing

# with dim
indices <- 1:dim(seleno_df_noDups)[1]

# with length
indices <- 1:length(seleno_df_noDups$gene)

or hard-coded

indices <- 1:37

We can then use SAMPLE() to select 2 random numbers from this vector.

For x = we’ll use our vector of indices (1 to 37). For size we’ll use 2, since we want to pull out just 2 numbers. For replace we’ll use FALSE since we don’t want to be able to select the same number twice.

i.random.genes <- sample(x = indices,
                         size = 2,
                         replace = FALSE)

Hard coded this would be

i.random.genes <- sample(x = c(1:37),
                         size = 2,
                         replace = FALSE)

This gives me 2 indices values.

i.random.genes
## [1] 20 21

I can now use these index values to pull out 2 rows of data

seleno_df_noNA[i.random.genes, ]
##    gene protein_refseq
## 27 GPX4 NP_001034936.1
## 28 GPX4 NP_001034937.1

Hard coded, this would be something like this for whichever genes happen to have been selected

seleno_df_noNA[c(37,15), ]
##       gene protein_refseq
## 47 SELENOS    NP_060915.2
## 19    GPX1 NP_001316384.1

Downloading genes

I will now DOWNLOAD THE FASTA FILES

rentrez::entrez_fetch(id = "NP_060915.2",
                      db = "protein",
                      rettype = "fasta")
## [1] ">NP_060915.2 selenoprotein S isoform 1 [Homo sapiens]\nMERQEESLSARPALETEGLRFLHTTVGSLLATYGWYIVFSCILLYVVFQKLSARLRALRQRQLDRAAAAV\nEPDVVVKRQEALAAARLKMQEELNAQVEKHKEKLKQLEEEKRRQKIEMWDSMQEGKSYKGNAKKPQEEDS\nPGPSTSSVLKRKSDRKPLRGGGYNPLSGEGGGACSWRPGRRGPSSGGUG\n\n"
rentrez::entrez_fetch(id = "NP_001316384.1",
                      db = "protein",
                      rettype = "fasta")
## [1] ">NP_001316384.1 glutathione peroxidase 1 isoform 5 [Homo sapiens]\nMCAARLAAAAAAAQSVYAFSARPLAGGEPVSLGSLRGKENAKNEEILNSLKYVRPGGGFEPNFMLFEKCE\nVNGAGAHPLFAFLREALPAPSDDATALMTDPKLITWSPVCRNDVAWNFEKFLVGPDGVPLRRYSRRFQTI\nDIEPDIEALLSQGPSCA\n\n"

THIS IS ASSIGNING VARIABLE NAMES TO THE FASTA FILES

prot1 <- rentrez::entrez_fetch(id = "NP_060915.2",
                      db = "protein",
                      rettype = "fasta")

prot2 <- rentrez::entrez_fetch(id = "NP_001316384.1",
                      db = "protein",
                      rettype = "fasta")

I can put them into a LIST like this

# make the LIST
seleno_thingy <- vector("list", 1)


# add the first fasta
seleno_thingy[[1]] <- prot1

# See the result
seleno_thingy
## [[1]]
## [1] ">NP_060915.2 selenoprotein S isoform 1 [Homo sapiens]\nMERQEESLSARPALETEGLRFLHTTVGSLLATYGWYIVFSCILLYVVFQKLSARLRALRQRQLDRAAAAV\nEPDVVVKRQEALAAARLKMQEELNAQVEKHKEKLKQLEEEKRRQKIEMWDSMQEGKSYKGNAKKPQEEDS\nPGPSTSSVLKRKSDRKPLRGGGYNPLSGEGGGACSWRPGRRGPSSGGUG\n\n"
# add the first fasta
seleno_thingy[[2]] <- prot2

# see the result
seleno_thingy
## [[1]]
## [1] ">NP_060915.2 selenoprotein S isoform 1 [Homo sapiens]\nMERQEESLSARPALETEGLRFLHTTVGSLLATYGWYIVFSCILLYVVFQKLSARLRALRQRQLDRAAAAV\nEPDVVVKRQEALAAARLKMQEELNAQVEKHKEKLKQLEEEKRRQKIEMWDSMQEGKSYKGNAKKPQEEDS\nPGPSTSSVLKRKSDRKPLRGGGYNPLSGEGGGACSWRPGRRGPSSGGUG\n\n"
## 
## [[2]]
## [1] ">NP_001316384.1 glutathione peroxidase 1 isoform 5 [Homo sapiens]\nMCAARLAAAAAAAQSVYAFSARPLAGGEPVSLGSLRGKENAKNEEILNSLKYVRPGGGFEPNFMLFEKCE\nVNGAGAHPLFAFLREALPAPSDDATALMTDPKLITWSPVCRNDVAWNFEKFLVGPDGVPLRRYSRRFQTI\nDIEPDIEALLSQGPSCA\n\n"
# THIS ADDS NAMES TO THE ITEMS OF THE LIST
names(seleno_thingy) <- c("prot1", "prot2")

#Output
seleno_thingy
## $prot1
## [1] ">NP_060915.2 selenoprotein S isoform 1 [Homo sapiens]\nMERQEESLSARPALETEGLRFLHTTVGSLLATYGWYIVFSCILLYVVFQKLSARLRALRQRQLDRAAAAV\nEPDVVVKRQEALAAARLKMQEELNAQVEKHKEKLKQLEEEKRRQKIEMWDSMQEGKSYKGNAKKPQEEDS\nPGPSTSSVLKRKSDRKPLRGGGYNPLSGEGGGACSWRPGRRGPSSGGUG\n\n"
## 
## $prot2
## [1] ">NP_001316384.1 glutathione peroxidase 1 isoform 5 [Homo sapiens]\nMCAARLAAAAAAAQSVYAFSARPLAGGEPVSLGSLRGKENAKNEEILNSLKYVRPGGGFEPNFMLFEKCE\nVNGAGAHPLFAFLREALPAPSDDATALMTDPKLITWSPVCRNDVAWNFEKFLVGPDGVPLRRYSRRFQTI\nDIEPDIEALLSQGPSCA\n\n"

Elements of the list are accessed like this

seleno_thingy[[1]]
## [1] ">NP_060915.2 selenoprotein S isoform 1 [Homo sapiens]\nMERQEESLSARPALETEGLRFLHTTVGSLLATYGWYIVFSCILLYVVFQKLSARLRALRQRQLDRAAAAV\nEPDVVVKRQEALAAARLKMQEELNAQVEKHKEKLKQLEEEKRRQKIEMWDSMQEGKSYKGNAKKPQEEDS\nPGPSTSSVLKRKSDRKPLRGGGYNPLSGEGGGACSWRPGRRGPSSGGUG\n\n"

I’ll clean them with fasta_cleaner()

# first, make a copy of the list for storing the clean data
## I'm just going to copy over the old data
seleno_thingy_clean <- seleno_thingy


# YOU COULD ALSO IMMEDIATELY SET THE CODE EQUAL TO SELENO_THINGY_CLEAN[[I]]
for(i in 1:length(seleno_thingy_clean)){
   clean_fasta_temp <- compbio4all::fasta_cleaner(seleno_thingy[[i]],
                                                       parse = T)
  
  seleno_thingy_clean[[i]] <- clean_fasta_temp
}

Now the data looks like this THE DATA IS NOW VECTORIZED AND SO EACH CHARACTER IS GIVEN A UNIQUE INDICES

seleno_thingy_clean
## $prot1
##   [1] "M" "E" "R" "Q" "E" "E" "S" "L" "S" "A" "R" "P" "A" "L" "E" "T" "E" "G"
##  [19] "L" "R" "F" "L" "H" "T" "T" "V" "G" "S" "L" "L" "A" "T" "Y" "G" "W" "Y"
##  [37] "I" "V" "F" "S" "C" "I" "L" "L" "Y" "V" "V" "F" "Q" "K" "L" "S" "A" "R"
##  [55] "L" "R" "A" "L" "R" "Q" "R" "Q" "L" "D" "R" "A" "A" "A" "A" "V" "E" "P"
##  [73] "D" "V" "V" "V" "K" "R" "Q" "E" "A" "L" "A" "A" "A" "R" "L" "K" "M" "Q"
##  [91] "E" "E" "L" "N" "A" "Q" "V" "E" "K" "H" "K" "E" "K" "L" "K" "Q" "L" "E"
## [109] "E" "E" "K" "R" "R" "Q" "K" "I" "E" "M" "W" "D" "S" "M" "Q" "E" "G" "K"
## [127] "S" "Y" "K" "G" "N" "A" "K" "K" "P" "Q" "E" "E" "D" "S" "P" "G" "P" "S"
## [145] "T" "S" "S" "V" "L" "K" "R" "K" "S" "D" "R" "K" "P" "L" "R" "G" "G" "G"
## [163] "Y" "N" "P" "L" "S" "G" "E" "G" "G" "G" "A" "C" "S" "W" "R" "P" "G" "R"
## [181] "R" "G" "P" "S" "S" "G" "G" "U" "G"
## 
## $prot2
##   [1] "M" "C" "A" "A" "R" "L" "A" "A" "A" "A" "A" "A" "A" "Q" "S" "V" "Y" "A"
##  [19] "F" "S" "A" "R" "P" "L" "A" "G" "G" "E" "P" "V" "S" "L" "G" "S" "L" "R"
##  [37] "G" "K" "E" "N" "A" "K" "N" "E" "E" "I" "L" "N" "S" "L" "K" "Y" "V" "R"
##  [55] "P" "G" "G" "G" "F" "E" "P" "N" "F" "M" "L" "F" "E" "K" "C" "E" "V" "N"
##  [73] "G" "A" "G" "A" "H" "P" "L" "F" "A" "F" "L" "R" "E" "A" "L" "P" "A" "P"
##  [91] "S" "D" "D" "A" "T" "A" "L" "M" "T" "D" "P" "K" "L" "I" "T" "W" "S" "P"
## [109] "V" "C" "R" "N" "D" "V" "A" "W" "N" "F" "E" "K" "F" "L" "V" "G" "P" "D"
## [127] "G" "V" "P" "L" "R" "R" "Y" "S" "R" "R" "F" "Q" "T" "I" "D" "I" "E" "P"
## [145] "D" "I" "E" "A" "L" "L" "S" "Q" "G" "P" "S" "C" "A"

SELENO_THINGY_CLEAN IS A TYPE OF VECTOR CALLED A LIST

class(seleno_thingy_clean[[1]])
## [1] "character"
is(seleno_thingy_clean[[1]])
##  [1] "character"               "vector"                 
##  [3] "data.frameRowLabels"     "SuperClassMethod"       
##  [5] "character_OR_connection" "character_OR_NULL"      
##  [7] "atomic"                  "EnumerationValue"       
##  [9] "vector_OR_Vector"        "vector_OR_factor"
is.vector(seleno_thingy_clean[[1]])
## [1] TRUE

Make a dotplot

For old-times sake we can make a dotplot.
Now for a dotplot

WE ASSIGNED EACH SEQUENCE TO ITS OWN VARIABLE

prot1_vector <- seleno_thingy_clean[[1]]
prot2_vector <- seleno_thingy_clean[[2]]

We can dotplot like this

seqinr::dotPlot(prot1_vector,
                prot1_vector)

HERE WE DIRECTLY ASSIGNED THE SEQUENCE TO THE DOTPLOT INSTEAD OF A VARIABLE FIRST

seqinr::dotPlot(seleno_thingy_clean[[1]],
                seleno_thingy_clean[[2]])

Pairwise alignment

dotPlot likes things in a single vector, but pairwiseAlignment like a single string of characters, so as always we have to process the data.

THIS CHUNK IS PROCESSING THE DATA AND TURNING A VECTOR INTO A STRING THE "" SHOWS THAT WE ARE PUTTING NO SPACE IN BETWEEN EACH CHARACTER

prot1_str <- paste(seleno_thingy_clean[[1]],sep = "", collapse = "")
prot2_str <- paste(seleno_thingy_clean[[2]],sep = "", collapse = "")

So now things look like this THIS IS NOW ONE CONTINUOUS STRING

prot1_str
## [1] "MERQEESLSARPALETEGLRFLHTTVGSLLATYGWYIVFSCILLYVVFQKLSARLRALRQRQLDRAAAAVEPDVVVKRQEALAAARLKMQEELNAQVEKHKEKLKQLEEEKRRQKIEMWDSMQEGKSYKGNAKKPQEEDSPGPSTSSVLKRKSDRKPLRGGGYNPLSGEGGGACSWRPGRRGPSSGGUG"

Protein alignments need an amino acid transition matrix, and we need to use data() to bring those up into active memory (VERY IMPORTANT STEP!)

data(BLOSUM50)

The alignment

align_out <- Biostrings::pairwiseAlignment(pattern = prot1_str, 
                              subject = prot2_str, 
                              type = "global",
                              gapOpening = -9.5,
                              gapExtension = -0.5)

THIS SHOWS THE MATCHES AT THE BEGINNING AND THE END OF THE SEQUENCE AS WELL AS THE SCORE

align_out
## Global PairwiseAlignmentsSingleSubject (1 of 1)
## pattern: MERQEESLSARPALETEGLRFLHTTVGSLLATYG...-----------------ACSWRPGRRGPSSGGUG
## subject: M---------------------------------...IDIEPDIEALLSQGPSCA----------------
## score: -160.2561

THIS SHOWS THE MATCHES OF THE ENTIRE SEQUENCE INSTEAD OF JUST THE BEGINNING AND END

compbio4all::print_pairwise_alignment(align_out)
## [1] "MERQEESLSARPALETEGLRFLHTTVGSLLATYGWYIVFSCILLYVVFQKLSARLRALRQ 60"
## [1] "M---------------------------------------C----------AARL----- 6"
## [1] " "
## [1] "RQLDRAAAAVEPDVVVKRQEALAAA--------RLKMQEELNAQVEKHKEKLKQLEEEKR 112"
## [1] "-----AAAA-------------AAAQSVYAFSAR-------------------------- 22"
## [1] " "
## [1] "RQKIEMWDSMQEGKSYKGNAKKPQEEDSPGPSTSSVLKRKSDRKPLRGGGYNPLSGE--- 169"
## [1] "--------------------------------------------PLAGG-------EPVS 31"
## [1] " "
## [1] "------------------------GGG--------------------------------- 172"
## [1] "LGSLRGKENAKNEEILNSLKYVRPGGGFEPNFMLFEKCEVNGAGAHPLFAFLREALPAPS 91"
## [1] " "
## [1] "------------------------------------------------------------ 172"
## [1] "DDATALMTDPKLITWSPVCRNDVAWNFEKFLVGPDGVPLRRYSRRFQTIDIEPDIEALLS 151"
## [1] " "
## [1] "-----A 227"
## [1] "QGPSCA 211"
## [1] " "

These are two randomly chosen sequences, so the alignment should be pretty BAD

The score is negative, but on its own that THERE ARE VERY FEW EXACT AND SIMILAR MATCHES OF AMINO ACIDS

score(align_out)
## [1] -160.2561

pid gives us THE PERCENTAGE OF AMINO ACIDS THAT ARE THE SAME

pid(align_out)
## [1] 7.189542

Of course, pid can be calculated several ways (THERE ARE DIFFERENT PIDS BASED ON WHETHER THE CODE IS CONSIDERING SIMILAR AMINO ACIDS WHICH CAN BE PROBLEMATIC WHEN IT IS NOT CLEAR TO THE READER WHICH PID IS BEING USED)

pid(align_out,type = "PID1")
## [1] 7.189542
pid(align_out,type = "PID2")
## [1] 91.66667
pid(align_out,type = "PID3")
## [1] 14.01274
pid(align_out,type = "PID4")
## [1] 12.71676