1. Anatomy of a MPSE

MicrobiotaProcess introduces MPSE S4 class. This class inherits the SummarizedExperiment(Morgan et al. 2021) class. Here, the assays slot is used to store the rectangular abundance matrices of features for a microbiome experimental results. The colData slot is used to store the meta-data of sample and some results about samples in the downstream analysis. The rowData is used to store the meta-data of features and some results about the features in the downstream analysis. Compared to the SummarizedExperiment object, MPSE introduces the following additional slots:

The structure of the MPSE class.

The structure of the MPSE class.

2. Overview of the design of MicrobiotaProcess package

With this data structure, MicrobiotaProcess will be more interoperable with the existing computing ecosystem. For example, the slots inherited SummarizedExperiment can be extracted via the methods provided by SummarizedExperiment. The taxatree and otutree can also be extracted via mp_extract_tree, and they are compatible with ggtree(Yu et al. 2017), ggtreeExtra(Xu et al. 2021), treeio(Wang et al. 2020) and tidytree(Yu 2021) ecosystem since they are all treedata class, which is a data structure used directly by these packages.

Moreover, the results of upstream analysis of microbiome based some tools, such as qiime2(Bolyen et al. 2019), dada2(Callahan et al. 2016) and MetaPhlAn(Beghini et al. 2021) or other classes (SummarizedExperiment(Morgan et al. 2021), phyloseq(McMurdie and Holmes 2013) and TreeSummarizedExperiment(Huang et al. 2021)) used to store the result of microbiome can be loaded or transformed to the MPSE class.

In addition, MicrobiotaProcess also introduces a tidy microbiome data structure paradigm and analysis grammar. It provides a wide variety of microbiome analysis procedures under a unified and common framework (tidy-like framework). We believe MicrobiotaProcess can improve the efficiency of related researches, and it also bridges microbiome data analysis with the tidyverse(Wickham et al. 2019).