Atacama Soil Microbiome#

In our example, we showcase the application of our QIIME2 plugins for high-dimensional statistics using the Atacama soil microbiome dataset [6]. With q2-gglasso we solve various graphical lasso problems to identify microbial associations which we later assess by fitting sparse log-contrast models implemented in q2-classo. Microbiome bioinformatics analyses were conducted using QIIME 2 version 2022.4 [1]. The processing of raw sequence data involved demultiplexing and quality filtering, facilitated by the q2-demux plugin. Subsequent denoising was performed using DADA2 [7] through the q2-dada2 plugin. Taxonomic assignments for Amplicon Sequence Variants (ASVs) were accomplished using the q2-feature-classifier [8] with the naive Bayes taxonomy classifier, trained on the Silva Database [9].

Data Preprocessing Pipeline#

Here is the original code for Atacama example data preprocessing. One can simply follow the original Atacama tutorial, but we wanted to give these ASVs meaningful names for the sake of this example. That’s why we rename the ASV keys as follows:

ASV label

Real ASV ID

ASV-1

89cb1ddf89dcf11d86f725dbcaa9a5ce

ASV-2

cdb9c0ee3bba4c3d8b9292eb575bd9e3

ASV-3

4c8ff0ea98d2c0ebb486e33bd96c61f9

ASV-4

a56b903521b8ab33a7878b35582803a8

ASV-5

5c78314ff92e6fec9aa07acc1fa0dc24

ASV-6

dc8a2f47b3d1dc2e1f5f805891976b29

ASV-7

6b780e361cfc5f06def718518324bdcb

ASV-8

f6c10a04d57159c0d64d6bc30c677471

ASV-9

ffd60d684f32e6fd5b47fe90095f9d34

ASV-10

ef3fdbe1dcde754d91130cde6a4b4d61

ASV-11

a36b38f754f6abd278aeb9dbc7696343

ASV-12

a7b877ae6d2f079a15b6b192a4425620

ASV-13

409faa5f5353e543bf6d99125c7c0e83

Data for Downstream analysis#

We’ll use the Atacama soil microbiome dataset [6], which contains:

  • 49 samples from Atacama Desert soil;

  • 13 microbial taxa (ASVs)

  • Environmental covariates: pH, elevation, temperature, humidity, and vegetayion

The original data is available through the European Nucleotide Archive under accession ERP019482.

Sample ID

ASV-1

ASV-2

ASV-3

ASV-11

ASV-12

ASV-13

Elevation

pH

Avg Soil RH

Avg Soil Temp

Vegetation

BAQ2420.1.1

0.0

11.0

0.0

115.0

0.0

0.0

2420

9.33

82.54

22.45

no

BAQ2420.1.2

0.0

0.0

0.0

0.0

0.0

0.0

2420

9.36

82.54

22.45

no

BAQ2420.1.3

0.0

0.0

0.0

0.0

0.0

0.0

2420

8.90

82.54

22.45

no

YUN3856.2

6.0

13.0

26.0

0.0

0.0

104.0

3856

7.43

99.44

9.51

yes

YUN3856.3

21.0

36.0

23.0

33.0

0.0

0.0

3856

7.43

99.44

9.51

yes

QIIME2 .qza file can be downloaded from this link, here is the snapshot of the count data and corresponding metadata we’re using in our example.