Distribution of cold adaptation proteins in microbial mats in Lake Joyce, Antarctica: Analysis of metagenomic data by using two bioinformatics tools

Academic Article

Abstract

  • © 2015 Elsevier B.V. In this study, we report the distribution and abundance of cold-adaptation proteins in microbial mat communities in the perennially ice-covered Lake Joyce, located in the McMurdo Dry Valleys, Antarctica.Wehave usedMGRAST and R code bioinformatics tools on Illumina HiSeq2000 shotgun metagenomic data and compared the filtering efficacy of these two methods on cold-adaptation proteins. Overall, the abundance of cold-shock DEAD-box protein A (CSDA), antifreeze proteins (AFPs), fatty acid desaturase (FAD), trehalose synthase (TS), and cold-shock family of proteins (CSPs)were present in all mat samples at high, moderate, or lowlevels,whereas the ice nucleation protein (INP) was present only in the ice and bulbous mat samples at insignificant levels. Considering the near homogeneous temperature profile of Lake Joyce (0.08-0.29 °C), the distribution and abundance of these proteins across various mat samples predictively correlatedwith known functional attributes necessary for microbial communities to thrive in this ecosystem. The comparison of the MG-RAST and the R code methods showed dissimilar occurrences of the cold-adaptation protein sequences, though with insignificant ANOSIM (R = 0.357; p-value = 0.012), ADONIS (R2= 0.274; p-value = 0.03) and STAMP (p-values = 0.521- 0.984) statistical analyses. Furthermore, filtering targeted sequences using the R code accounted for taxonomic groups by avoiding sequence redundancies,whereas theMG-RAST provided total counts resulting in a higher sequence output. The results fromthis study revealed for the first time the distribution of cold-adaptation proteins in six different types of microbial mats in Lake Joyce, while suggesting a simpler and more manageable userdefined method of R code, as compared to a web-based MG-RAST pipeline.
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    Digital Object Identifier (doi)

    Author List

  • Koo H; Hakim JA; Fisher PRE; Grueneberg A; Andersen DT; Bej AK
  • Start Page

  • 23
  • End Page

  • 28
  • Volume

  • 120