Antarctic desert soil bacteria exhibit high novel natural product potential, evaluated through long‐read genome sequencing and comparative genomics. (10th November 2020)

• Record Type: Journal Article
• Authors: Benaud, Nicole; Edwards, Richard J.; Amos, Timothy G.; D'Agostino, Paul M.; Gutiérrez‐Chávez, Carolina; Montgomery, Kate; Nicetic, Iskra; Ferrari, Belinda C.
• Other Names: Hallsworth John E. guestEditor.; Amils Ricardo guestEditor.; Benison Kathleen C. guestEditor.; Cavalazzi Barbara guestEditor.; Davila Alfonso F. guestEditor.; Madigan Michael T. guestEditor.; Selbmann Laura guestEditor.; Westall Frances guestEditor.
• Is Part Of: Environmental microbiology. Volume 23:Number 7(2021)
• Page Start: 3646
• Page End: 3664
• Publication Date: 2020-11-10
• Subjects: Microbial ecology -- Periodicals; Environmental Microbiology -- Periodicals; 579.17
• DOI: 10.1111/1462-2920.15300
• Languages: English
• ISSNs: 1462-2912

Abstract

Summary: Actinobacteria and Proteobacteria are important producers of bioactive natural products (NP), and these phyla dominate in the arid soils of Antarctica, where metabolic adaptations influence survival under harsh conditions. Biosynthetic gene clusters (BGCs) which encode NPs, are typically long and repetitious high G + C regions difficult to sequence with short‐read technologies. We sequenced 17 Antarctic soil bacteria from multi‐genome libraries, employing the long‐read PacBio platform, to optimize capture of BGCs and to facilitate a comprehensive analysis of their NP capacity. We report 13 complete bacterial genomes of high quality and contiguity, representing 10 different cold‐adapted genera including novel species. Antarctic BGCs exhibited low similarity to known compound BGCs (av. 31%), with an abundance of terpene, non‐ribosomal peptide and polyketide‐encoding clusters. Comparative genome analysis was used to map BGC variation between closely related strains from geographically distant environments. Results showed the greatest biosynthetic differences to be in a psychrotolerant Streptomyces strain, as well as a rare Actinobacteria genus, Kribbella, while two other Streptomyces spp. were surprisingly similar to known genomes. Streptomyces and Kribbella BGCs were predicted to encode antitumour, antifungal, antibacterial and biosurfactant‐like compounds, and the synthesis of NPs with antibacterial, antifungal and surfactant properties was confirmed through bioactivity assays.