Corallococcus soli sp. Nov., a Soil Myxobacterium Isolated from Subtropical Climate, Chalus County, Iran, and Its Potential to Produce Secondary Metabolites

Abstract

A novel myxobacterial strain ZKHCc1 1396T was isolated in 2017 from a soil sample collected along Chalus Road connecting Tehran and Mazandaran, Iran. It was a Gram-negative, rod-shaped bacterial strain that displayed the general features of Corallococcus, including gliding and fruiting body formation on agar and microbial lytic activity. Strain ZKHCc1 1396T was characterized as an aerobic, mesophilic, and chemoheterotrophic bacterium resistant to many antibiotics. The major cellular fatty acids were branched-chain iso-C17:0 2-OH, iso-C15:0, iso-C17:1, and iso-C17:0. The strain showed the highest 16S rRNA gene sequence similarity to Corallococcus terminator CA054AT (99.67%) and C. praedator CA031BT (99.17%), and formed a novel branch both in the 16S rRNA gene sequence and phylogenomic tree. The genome size was 9,437,609 bp, with a DNA G + C content of 69.8 mol%. The strain had an average nucleotide identity (ANI) value lower than the species cut-off (95%), and with the digital DNA–DNA hybridization (dDDH) below the 70% threshold compared to the closest type strains. Secondary metabolite and biosynthetic gene cluster analyses revealed the strain’s potential to produce novel compounds. Based on polyphasic taxonomic characterization, we propose that strain ZKHCc1 1396T represents a novel species, Corallococcus soli sp. nov. (NCCB 100659T = CIP 111634T).

Bacterial Communities of Lamiacea L. Medicinal Plants: Structural Features and Rhizosphere Effect

“…Myxococcota are Gram-negative, mainly aerobic sticks, that habituate in the soil, which are characterized by a complex development cycle, high socialization and the ability to form fruiting bodies. Having a sliding motion due to dense mucous cords, these bacteria are characterized as chemoorganoheterotrophs, some representatives being able to decompose cellulose and chitin, as well as being able to form antibiotic resistance [ 62 , 63 ]. This bacterial taxon is considered more abundant in the rhizosphere than outside of it.…”

Chromosomal organization of biosynthetic gene clusters suggests plasticity of myxobacterial specialized metabolism including descriptions for nine novel species:Archangium lansiniumsp. nov.,Myxococcus landrumussp. nov.,Nannocystis bainbridgeasp. nov.,Nannocystis poenicansasp. nov.,Nannocystis radixulmasp. nov.,Polyangium mundeleiniumsp. nov.,Pyxidicoccus parkwaysissp. nov.,Sorangium ateriumsp. nov.,Stigmatella ashevillenasp. nov

“…Myxobacteria are excellent resources for discovery of therapeutics and are suggested to be keystone taxa influencing polymicrobial community structure in soil (1,2, 66–68). Recent discoveries of novel Corallococcus, Myxococcus , and Pyxidicoccus species as well as species from lesser-studied genera indicate an abundance of uncharacterized myxobacteria (10–12, 14–17, 69–79). Our investigation of rhizospheric soil samples provided 20 environmental myxobacteria including 9 proposed novel species.…”

“…Ongoing natural product discoveries from novel species of myxobacteria reinforce the need for continued isolation and characterization of environmental myxobacteria (6)(7)(8)(9). Most recently described Myxococcota belong to the genera Corallococcus, Myxococcus, and Pyxidicoccus (10)(11)(12)(13)(14), and comparatively fewer members of lesser-studied myxobacterial taxa have been reported over the last decade (15)(16)(17). For example, no new type strain Stigmatella has been reported since 2007.…”

Insights into the Belowground Biodiversity and Soil Nutrient Status of an Organic Apple Orchard as Affected by Living Mulches

“…The soil bacteria microbiome associated with F. vesca was enriched with microorganisms, which are either described as endosymbionts of AMF (e.g., Candidatus Glomeribacter) [39] or present in the earthworm gut microbiome (e.g., Candidatus Lumbricinola) [40] as well as microorganisms identified in various soil environments, like Psychrobacter [41] or Buttiauxella [42,43], suggesting that the use of F. vesca as a living mulch could affect the soil environment at different levels of the trophic network. Taxa specific only to A. vulgaris, e.g., Corallococcus, Patescibacteria, or Geminicoccaceae, have been rarely explored [44][45][46]; thus, their importance and functional role in orchard soil environments need further study. Bacteria taxa characteristic to the M. x piperita soil microbiome are poorly known; however, some of them, like Micromonospora, are known to colonize plant rhizosphere, particularly N-fixing species [47], have already been isolated from mint species [48], allowing us to hypothesize a specific plant-bacteria association or the selection of this taxa by the living mulch species that could be useful in terms of nutrient cycling or plant protection.…”