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Microbiome_pooled_analysis_bacteria.qmd
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---
title: "Microbiome: Pooled analysis bacteria"
subtitle: "Indoor dust bacterial and fungal microbiota composition and allergic diseases: a scoping review"
author:
- "Javier Mancilla Galindo, MSc student"
- "Supervisors: Inge M. Wouters and Alex Bossers"
- "Examiner: Lidwien A.M. Smit"
date: today
execute:
echo: false
warning: false
toc: true
format:
pdf:
documentclass: scrartcl
bibliography: ../docs/manuscript/references-dust-microbiome-review.bib
csl: ../docs/manuscript/environment-international.csl
editor: source
---
\pagebreak
```{r}
#| include: false
# random seed
seed <- 2202
# load Alex Bossers helper functions
source("scripts/00_helperfunctions/alx_OutOfSight.R")
```
```{r}
#| include: false
# Create directories
inputfolder <- "../data/raw/literature_seqdata_dada2/SeqData_dada2/"
psfolder <- "../data/processed"
tabfolder <- "../results/output_tables/bacteria"
figfolder <- "../results/output_figures/bacteria"
dir.create(psfolder, showWarnings = FALSE)
dir.create(tabfolder, showWarnings = FALSE)
dir.create(figfolder, showWarnings = FALSE)
```
```{r}
#| include: false
# load required libraries. Install them if not available.
#
# if BiocManager asks you to additionally update some packages...
# only choose 'a' if you can spare the time!
# sometimes these updates (especially if many) can take a loooong time to complete.
# A restart of R before installing is good practice to unload any packages present in memory.
# install phyloseq and associated vegan microbial community ecology packages
if ( !require("phyloseq", quietly = TRUE) )
BiocManager::install("phyloseq")
# install additional color scales
if ( !require("RColorBrewer", quietly = TRUE) )
BiocManager::install("RColorBrewer")
# install more convenient color scales
if ( !require("pals", quietly = TRUE) )
BiocManager::install("pals")
# install date handling functions
if ( !require("lubridate", quietly = TRUE) )
BiocManager::install("lubridate")
# Reference packages used in session
if ( !require("gt", quietly = TRUE) )
BiocManager::install("gt")
# Retrieve html tables
if ( !require("htmltools", quietly = TRUE) )
BiocManager::install("htmltools")
# Reference packages used in session
if ( !require("report", quietly = TRUE) )
BiocManager::install("report")
```
\pagebreak
# Session
```{r}
# Log session info:
# Credits chunk of code: Alex Bossers, Utrecht University
session <- sessionInfo()
# remove clutter
session$BLAS <- NULL
session$LAPACK <- NULL
session$loadedOnly <- NULL
# write log file
writeLines(
capture.output(print(session, locale = FALSE)),
paste0("sessions/",lubridate::today(), "_session_Microbiome_Data_bacteria.txt")
)
session
```
\pagebreak
# Description
A selection of studies included in the scoping review that had available raw sequence data and a comparable dust collection method were identified to retrieve sequence data to undergo processing in the same pipeline, as a proof of concept that pooled analyses could offer insight into the composition of the indoor dust microbiome and to identify potential needs and difficulties for the performance of such pooled microbiome analyses. The type of indoor environment was restricted to dwellings as this was the most common type of indoor environment. A total of **4 studies**[@fakunle2023a; @amin2022a; @vestergaard2018a; vandenborght2021a] following the electrostatic dust collector (EDC) method and **2 studies**[@hickman2022a; @adams2020a] using the petri dish method were selected due to the known comparability of these sample collection methods.[@adams2015a] Additionally, previously unpublished data from a study sampling Dutch households with the EDC method was also included. Out of the 7 studies, 6 studies reported bacterial indoor dust sequences, whereas 5 made fungal ITS sequences publicly available.
This report includes the processing and analysis of **bacterial 16S** sequences.
## Nigerian[@fakunle2023a] and Dutch (unpublished) households
Dutch and Nigerian indoor dust samples follow similar methods of collection through EDC and were processed and analyzed together in the laboratory. These samples have been sequenced for the 16S rRNA combined V5-V6 hypervariable region for bacteria, and the ITS1 region between the 18S and 5.8S rRNA subunits for fungi. After processing, these were compared against the SILVA (bacteria) and UNITE datasets to determine the microbial composition of the samples.
The Dutch samples are from a cross-sectional study aiming to assess environmental factors as determinants of the indoor house dust microbial composition. The study population consisted of households located in Utrecht and surrounding areas of whose inhabitants were invited between April and May 2017 to participate in a survey in which diverse household characteristics, socioeconomic data, and health status variables were collected, as well as airborne dust samples from the household. Participants were instructed to place electrostatic dust collectors at a height of at least 1.25 meters above floor level in the main living room. Out of 600 homes selected to represent different housing characteristics, to which invitations were sent, seventy-nine ultimately provided the answered questionnaires and household dust samples. Only one adult per household provided responses to the questionnaire including their health status and was responsible for collecting and delivering the samples.
The Nigerian samples are from a case-control study of the relationship between indoor airborne dust microbiome and childhood lower respiratory tract infections.[@fakunle2023a]
Phyloseq object containing both NL and NG samples + controls:
```{r}
bacter_NL_fakunle2023a <- readRDS(
paste0(inputfolder,
"/Updated_set1+2_16S-v5v6_Nigerian+NL_dust+controls_20240614.rds")
)
bacter_NL_fakunle2023a
```
Only residential households were kept, since this was similarly done with retrieved samples from studies captured in the literature review to reduce the number of samples to process. This was done under the assumption that quality control has already been done for all published and unpublished studies.
Phyloseq object containing both NL and NG samples, after removing controls:
```{r}
bacter_NL_fakunle2023a <- subset_samples(bacter_NL_fakunle2023a, Sam_type %in% c("NL","NG"))
bacter_NL_fakunle2023a
```
```{r}
sample_sum_plot(bacter_NL_fakunle2023a)
```
Since there is limited metadata from other studies that would allow comparison by additional environmental determinants or health outcome, this analysis will be limited to a comparison by the country of origin of the samples.
```{r}
sample_data(bacter_NL_fakunle2023a) <- sample_data(bacter_NL_fakunle2023a) %>%
data.frame %>%
select(SamID, Sam_type) %>%
rename(SampleNames = SamID, Country = Sam_type) %>%
mutate(
Collector = "EDC",
Study = case_when(
Country == "NG" ~ "NG_fakunle2023",
Country == "NL" ~ "NL_unpublished",
)
)
```
\pagebreak
## Finnish households [@hickman2022a]
[**PRJNA892469**](https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA892469)
```{r}
bacter_hickman2022a <- readRDS(
paste0(inputfolder,
"/20240412_Javier_PRJNA892469bac_merged_NAfilled.rds")
)
bacter_hickman2022a
```
```{r}
sample_sum_plot(bacter_hickman2022a)
```
```{r}
sample_data(bacter_hickman2022a) <- sample_data(bacter_hickman2022a) %>%
data.frame %>%
mutate(
Country = "FI",
Collector = "petri",
Study = "FI_hickman2022"
)
```
\pagebreak
## Danish households
[**PRJNA801418**](https://www.ncbi.nlm.nih.gov/bioproject/PRJNA801418) corresponds to cow farmers' homes[@amin2022a], and [**PRJNA417363 / SRP124427**](https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA417363), to pig farmers' homes and suburban dwellings.[@vestergaard2018a]
## [@amin2022a]
```{r}
bacter_amin2022a <- readRDS(
paste0(inputfolder,
"/20240412_Javier_PRJNA801418bac_merged_NAfilled.rds")
)
bacter_amin2022a
```
```{r}
sample_sum_plot(bacter_amin2022a)
```
```{r}
sample_data(bacter_amin2022a) <- sample_data(bacter_amin2022a) %>%
data.frame %>%
mutate(
Country = "DK",
Collector = "EDC",
Study = "DK_amin2022"
)
```
\pagebreak
## [@vestergaard2018a]
[**PRJNA635002**](https://www.ncbi.nlm.nih.gov/bioproject/?term=PRJNA635002)
```{r}
bacter_vestergaard2018a <- readRDS(
paste0(inputfolder,
"/20240412_Javier_SRP124427bac_merged_NAfilled.rds")
)
bacter_vestergaard2018a
```
```{r}
sample_sum_plot(bacter_vestergaard2018a)
```
```{r}
sample_data(bacter_vestergaard2018a) <- sample_data(bacter_vestergaard2018a) %>%
data.frame %>%
mutate(
Country = "DK",
Collector = "EDC",
Study = "DK_vestergaard2018"
)
```
\pagebreak
## [@vandenborght2021a]
```{r}
bacter_vandenborght2021a <- readRDS(
paste0(inputfolder,
"/20240412_Javier_PRJNA635002bac_merged_NAfilled.rds")
)
bacter_vandenborght2021a
```
```{r}
sample_sum_plot(bacter_vandenborght2021a)
```
```{r}
sample_data(bacter_vandenborght2021a) <- sample_data(bacter_vandenborght2021a) %>%
data.frame %>%
mutate(
Country = "FR",
Collector = "EDC",
Study = "FR_vandenborght2021a"
)
```
\pagebreak
# Merge phyloseq objects
Check if rank names are equal
```{r}
rank_names(bacter_NL_fakunle2023a)
rank_names(bacter_hickman2022a)
rank_names(bacter_amin2022a)
rank_names(bacter_vestergaard2018a)
rank_names(bacter_vandenborght2021a)
```
The GenusSpecies rank is missing in the NL and NG data. I will remove it and check if they are now equal:
```{r}
tax_table(bacter_hickman2022a) <- tax_table(bacter_hickman2022a)[, -which(rank_names(bacter_hickman2022a) == "GenusSpecies")]
tax_table(bacter_amin2022a) <- tax_table(bacter_amin2022a)[, -which(rank_names(bacter_amin2022a) == "GenusSpecies")]
tax_table(bacter_vestergaard2018a) <- tax_table(bacter_vestergaard2018a)[, -which(rank_names(bacter_vestergaard2018a) == "GenusSpecies")]
tax_table(bacter_vandenborght2021a) <- tax_table(bacter_vandenborght2021a)[, -which(rank_names(bacter_vandenborght2021a) == "GenusSpecies")]
all.equal(
rank_names(bacter_hickman2022a),
rank_names(bacter_amin2022a),
rank_names(bacter_vestergaard2018a),
rank_names(bacter_vandenborght2021a),
rank_names(bacter_NL_fakunle2023a)
)
```
Merge into a single phyloseq object
```{r}
#| eval: false
# Merge the phyloseq objects
bacter <- merge_phyloseq(
bacter_hickman2022a,
bacter_amin2022a,
bacter_vestergaard2018a,
bacter_vandenborght2021a,
bacter_NL_fakunle2023a
)
rm(bacter_hickman2022a, bacter_amin2022a, bacter_vestergaard2018a,bacter_NL_fakunle2023a, bacter_vandenborght2021a)
```
Save unrarefied data:
```{r}
#| echo: true
#| eval: false
saveRDS(
bacter,
paste0(psfolder,"/bacter_combined.rds")
)
```
\pagebreak
Sample sums plot:
```{r}
#| echo: false
#| eval: false
sample_sum_plot(bacter, color = "Country", percentKeep = 95)
ggsave(
filename = "sample_sum_plot_bacteria.png",
path = figfolder,
width = 12,
height = 8,
units = "in",
dpi = 300
)
```
![](images/sample_sum_plot_bacteria.png){fig-align="center"}
I will keep 95% of samples.
```{r}
#| eval: false
sample_sums <- sample_sums(bacter)
samples_keep <- names(sample_sums[sample_sums >= 5513])
bacter <- prune_samples(samples_keep, bacter)
rm(sample_sums)
#Check that it matches number in figure
nsamples(bacter)
```
Save `bacter_keep`:
```{r}
#| echo: true
#| eval: false
saveRDS(
bacter,
paste0(psfolder,"/bacter_keep.rds")
)
```
The construction of rarefaction curves was done with the following script:
```{r}
#| eval: false
#| echo: true
source("scripts/rarefaction_plot_bacter.R")
```
![](images/rarefaction_curves_bacter.png){fig-align="center"}
Rarefying above 10,000 leads to very large losses of samples. Thus, I will rarefy at 10,000 which leads to loosing close to \~10% (n=79) of samples.
```{r}
#| eval: false
#| echo: true
bacter_rar <- rarefy_even_depth(
bacter,
sample.size=10000,
rngseed=seed,
replace=FALSE
)
bacter_rar
```
`79 samples removed because they contained fewer reads than sample.size. 115622OTUs were removed because they are no longer present in any sample after random subsampling`
The number of samples is now 710.
```{r}
#| eval: false
saveRDS(
bacter_rar,
paste0(psfolder,"/bacter_rar.rds")
)
```
\pagebreak
# Alpha diversity
### ASV level
```{r}
#| eval: false
alphaplot <- plot_richness(
bacter_rar,
measures=c("Observed", "Shannon"),
x="Country"
)
ggsave(
plot = alphaplot,
filename = "alphaplot_rarefied.png",
path = figfolder,
width = 12,
height = 8,
units = "in",
dpi = 300
)
```
![](images/alphaplot_bacter_rarefied.png){fig-align="center"}
\pagebreak
### Genus level
```{r}
#| eval: false
# Agglomerate at genus level and save
bacter_rar_genus <- tax_glom(bacter_rar, taxrank="Genus")
saveRDS(
bacter_rar_genus,
paste0(psfolder,"/bacter_rar_genus.rds")
)
```
```{r}
#| eval: false
alphaplot <- plot_richness(
bacter_rar_genus,
measures=c("Observed", "Shannon"),
x="Country"
)
ggsave(
plot = alphaplot,
filename = "alphaplot_rarefied_genus.png",
path = figfolder,
width = 12,
height = 8,
units = "in",
dpi = 300
)
alphaplot_violin <- alphaplot + geom_violin()
ggsave(
plot = alphaplot_violin,
filename = "alphaplot_rarefied_genus_violin.png",
path = figfolder,
width = 12,
height = 8,
units = "in",
dpi = 300
)
```
![](images/alphaplot_bacter_rarefied_genus_violin.png){fig-align="center"}
\pagebreak
# Relative abundance
```{r}
#| eval: false
# Convert to relative abundance
bacter_rar <- transform_sample_counts(
bacter_rar,
function(x) x / sum(x) * 100
)
# Save
saveRDS(
bacter_rar,
paste0(psfolder,"/bacter_rar_relative.rds")
)
```
The figures were generated with the following script:
```{r}
#| eval: false
#| echo: true
source("scripts/relative_abundance_plots_bacter.R")
```
![](images/bacter_Phylum_relative_abundance_top10.png){fig-align="center"}
\pagebreak
![](images/bacter_Class_relative_abundance_top14.png){fig-align="center"}
\pagebreak
![](images/bacter_Order_relative_abundance_top30.png){fig-align="center"}
\pagebreak
![](images/bacter_Family_relative_abundance_top30.png){fig-align="center"}
\pagebreak
![](images/bacter_Genus_relative_abundance_top35.png){fig-align="center"}
\pagebreak
# Beta diversity (Genus level)
## PCoA
PCoA plot will be generated with the following code:
```{r}
#| eval: false
#| echo: true
source("scripts/ordination_plots_bacteria.R")
```
### Axes 1 and 2
![](images/PCoA_bacter.png){fig-align="center"}
\pagebreak
### Axes 1 and 3
![](images/PCoA_bacter_axes1and3.png){fig-align="center"}
\pagebreak
## Hellinger transformed
Perhaps there is improvement with Hellinger transformation:
### Axes 1 and 2
![](images/PCoA_bacter_hellinger.png){fig-align="center"}
\pagebreak
### Axes 1 and 3
![](images/PCoA_bacter_hellinger_axes1and3.png){fig-align="center"}
\pagebreak
## NMDS
### Axes 1 and 2
![](images/NMDS_bacter_hellinger.png){fig-align="center"}
\pagebreak
### Axes 1 and 3
![](images/NMDS_bacter_hellinger_axes1and3.png){fig-align="center"}
\pagebreak
# Permanova
Permanova done with the following code:
```{r}
#| eval: false
#| echo: true
source("scripts/permanova_bacteria.R")
```
### Results Permanova
```{r}
includeHTML("../results/output_tables/bacteria/permanova_country_bacter.html")
```
### Dispersion Test
```{r}
dispersion <- readRDS("../results/output_tables/bacteria/dispersion_country_bacter.rds")
dispersion
```
\pagebreak
### Pairwise Permanova
```{r}
includeHTML("../results/output_tables/bacteria/pairwise_permanova_country_bacter.html")
```
Updated figure (NMDS hellinger transformed plot):
```{r}
#| eval: false
nmds_plot <- readRDS("../results/output_figures/bacteria/beta_diversity/Country/NMDS_bacter_hellinger_plot.rds")
nmds_plot +
labs(title = "PERMANOVA: R² = 0.37, p < 0.001") +
theme(plot.title = element_text(hjust = 1))
ggsave(
filename = paste0(figfolder,"/NMDS_bacter_country_updated.png"),
width = 9,
height = 7,
dpi = 300
)
```
![](images/NMDS_bacter_country_updated.png){fig-align="center"}
\pagebreak
# Package References
```{r}
#| include: false
report::cite_packages(session)
```
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# Study References