Complete Genome Sequence and Comparative Genomics of a Novel Myxobacterium Myxococcus hansupus.

Gaurav Sharma,Tarun Narwani,Srikrishna Subramanian,Feng Gao

doi:10.1371/journal.pone.0148593

Abstract

Myxobacteria, a group of Gram-negative aerobes, belong to the class δ-proteobacteria and order Myxococcales. Unlike anaerobic δ-proteobacteria, they exhibit several unusual physiogenomic properties like gliding motility, desiccation-resistant myxospores and large genomes with high coding density. Here we report a 9.5 Mbp complete genome of Myxococcus hansupus that encodes 7,753 proteins. Phylogenomic and genome-genome distance based analysis suggest that Myxococcus hansupus is a novel member of the genus Myxococcus. Comparative genome analysis with other members of the genus Myxococcus was performed to explore their genome diversity. The variation in number of unique proteins observed across different species is suggestive of diversity at the genus level while the overrepresentation of several Pfam families indicates the extent and mode of genome expansion as compared to non-Myxococcales δ-proteobacteria.

Highlights

Myxobacteria are Gram-negative δ-proteobacteria [1, 2] which are mostly aerobic with some notable exception such as Anaeromyxobacter [3]
The analysis reveals that M. stipitatus [16] (Ms). stipitatus show the minimum orthology protein pairs with other species followed by M. hansupus (Mh) and M. fulvus HW-1 (Mf)
The current study reports the complete 9.5 Mbp genome of a novel Myxobacteria, M. hansupus and its comparative analysis with five previously available Myxococcus genomes. 16S rRNA, housekeeping genes phylogeny, and genome-genome distance suggest this organism is a novel species of the genus Myxococcus

Summary

Introduction

Myxobacteria are Gram-negative δ-proteobacteria [1, 2] which are mostly aerobic with some notable exception such as Anaeromyxobacter [3]. Myxobacteria form complex fruiting bodies composed of dormant myxospores, analogous to stalk formation in higher-order fungi [10, 11]. Owing to their complex life cycle, Myxobacteria contain many proteins involved in signal transduction pathways and transcriptional regulation [2]. These proteins help in regulating cell-cell communication and coordinate social motility and fruiting body formation. Besides these unique physiological properties, the relatively large genome size (4.5–15 Mbp) is a characteristic feature of order Myxococcales that distinguish it from other δ-proteobacteria (typically 2–7 Mbp)

Methods

Results

Conclusion