Diversity and differences of transmembrane transporter genes in the microbiome between different biological soil crusts

Abstract:

[Background] Transmembrane transporters play important roles in the transport process of various substances by microorganisms. [Objective] By comparing the difference of genes encoding phosphotransferase system (PTS system) and ATP-binding cassette transporter (ABC transporter) in the prokaryotic microbiome between cyanobacteria and moss biocrusts, it will reveal the potential change trends in the biological processes of transmembrane transport along with the developmental succession of the biological soil crusts. [Methods] The metagenomic sequencing was performed for twelve samples of cyanobacteria and moss biocrusts collected from the southeastern of the Tengger desert. The sequencing data was compared with PTS system and ABC transporters metabolic pathway in KEGG database, then the related genes were selected and analyzed for the comparison between biocrusts. [Results] The gene diversity of PTS system and ABC transporter is consistent among cyanobacteria and moss biocrusts. A total of sixteen PTS system transporter genes were detected in the biocrusts, five of which had significant difference between cyanobacteria and moss biocrusts. 106 ABC transporters-encoding genes were detected, 46 of which were significantly changed. Then we have detailed descriptions of the substrates and shift trends of these 46 transporters. [Conclusion] In the process of the development and succession of biological soil crusts, the microbiome had a tendency to reduce substances uptake from the environment that can increase the osmotic potential and increase the potential of amino acids, cell membrane and cell wall components transportation, while there was no significant changes in the transport of mineral ions, auxiliary factors, sugars and carbohydrates. It should be noted that the relationship between the diversity and difference of these transporter coding genes and biological soil crusts remains to be proved and explained experimently.

Key words:Biological soil crusts, Metagenomic sequencing, Phosphotransferase system, ABC transporter