Jenna M. Lang edited Methods.md  over 8 years ago

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###Comparison of ISS surfaces to analogous surfaces in homes on Earth and to the Human Microbiome Project  The sequences and associated metadata from a 40-home pilot study for the Wildlife of Our Homes Project are available for download from Figshare \cite{885e3742-e0c3-4719-a6a8-dba9930a33ca}. We also obtained 100 random samples from each of 13 body sites from the HMP Data Portal (http://hmpdacc.org/HM16STR/)\cite{Huttenhower_2012}\cite{Gevers_2012}. These two additional datasets were used in a combined analysis with the ISS sequences presented here. Because the sequences from the three projects are not all the same lengths, each dataset was independently analyzed using a closed-reference OTU-picking approach, with a 97% similarity cutoff, and the resultant biom tables were merged with the merge\_otu\_tables.py script. Shannon diversity, as well as non-metric multidimensional scaling (NMDS) based on Bray-Curtis and Unweighted Unifrac distances were computed and plotted using Phyloseq \cite{McMurdie_2013} and the ggplot2 \cite{Wilkinson_2011} packages in R \cite{R}.  ##Comparison to rooms with mechanical ventilation or open windows.  We obtained a list of human pathogens, compiled by Kembel et al, 2012 from the author. We then used BLAST to search a representative sequence from each of our OTUs against the NCBI Reference Sequence (RefSeq) database \cite{Pruitt_2004}. OTUs with 97% similarity to an organism that was on the list of known pathogens were flagged as "related to a known human pathogen". The phylogenetic diversity (Faith's PD) was calculated using the alpha\_diversity.py script, with samples rarefied to 700 sequences.