Unraveling the genomic diversity and ecological potential of the genus Demequina: insights from comparative analysis of different saline niche strains

Abstract

During an investigation of the culturable microbial diversity of sediments with salinity from tidal flats and saline lake, seven strains of the genus Demequina were harvested. The genomic analysis and physiological characteristics of strains of this genus have unveiled their significant potential in degrading complex carbon source such as lignin, hemicellulose, chitin, and oligosaccharides. In addition, these strains show potential abilities in nitrite ammonification and sulfide oxidation. These findings not only improved our understanding of their metabolic model, but also provided valuable insights into their ecological roles. Four new species of the genus Demequina are described: Demequina litoralis sp. nov., with SYSU T00192T designated as the type species; Demequina zhanjiangensis sp. nov., with SYSU T00b26T as the type species; Demequina lignilytica sp. nov., with SYSU T00068T as the type species; and Demequina muriae sp. nov., with EGI L300058T as the type species. Additionally, strains SYSU T0a273, SYSU T00039-1, and SYSU T00039 are identified as different strains of Demequina lignilytica. Our study thus sheds light on the diversity, biological significance, and ecological contribution of the Demequina genus in different habitats.

Demequina capsici sp. nov., a novel plant growth-promoting actinomycete isolated from the rhizosphere of bell pepper (Capsicum annuum)

“…Previous studies has highlighted that genus Demequina played critical roles in metabolic, complex carbon degradation, and energy cycles in the aquatic ecosystem 13 . Annotation of PMTSA13 T and OYTSA14 genomes revealed the presence of several carbon-degrading enzymes, such as cellulase, cellobiose, arabinofuranosidase, chitinase, α-galactosidase, β-galactosidase, α-glucosidase, and β-glucosidase.…”

“…One of the main characteristics of this genus is the presence of demethylmenaquinone (DMK) on its plasma membranes 9 – 11 , which is involved in nitrate respiration 12 . Demequina has been reported to possess significant capabilities for degrading complex carbon sources, nitrite ammonification, sulfide oxidation, and potential involvement in polyketide biosynthesis 13 . The typical characteristics of the Demequina genus, commonly found in coastal ecosystems, suggest its potential resilience in varying salinity conditions 13 .…”

“…Demequina has been reported to possess significant capabilities for degrading complex carbon sources, nitrite ammonification, sulfide oxidation, and potential involvement in polyketide biosynthesis 13 . The typical characteristics of the Demequina genus, commonly found in coastal ecosystems, suggest its potential resilience in varying salinity conditions 13 . Despite these characteristics, there is limited literature on the potential role of Demequina as PGPB.…”