Reclassification of Geobacillus galactosidasius and Geobacillus yumthangensis as Parageobacillus galactosidasius comb. nov. and Parageobacillus yumthangensis comb. nov., respectively

Abstract

Members of the genus Geobacillus within the phylum Firmicutes are Gram-stain-positive, aerobic, endospore-forming, obligate thermophiles. In 2016, the genus Geobacillus was subdivided into two genera based on whole-genome approaches. The new genus, Parageobacillus , comprises five genomospecies. In this study, we recommend the reclassification of two Geobacillus species, Geobacillus galactosidasius and Geobacillus yumthangensis , into the genus Parageobacillus . We have applied whole genome approaches to estimate the phylogenetic relatedness among the 18 Geobacillus and Parageobacillus type strains for which genome sequences are currently publicly available. The phylogenomic metrics AAI (average amino acid identity), ANI (average nucleotide identity) and dDDH (digital DNA–DNA hybridization) denoted that the type strains of G. galactosidasius and G. yumthangensis belong to the genus Parageobacillus . Furthermore, a phylogeny based on comparison of the 16S rRNA gene sequences, recN gene sequences and core genes identified from the whole-genome analyses designated that the type strains of G. galactosidasius and G. yumthangensis belong in the genus Parageobacillus . With these findings, we consequently propose that G. galactosidasius and G. yumthangensis should be reclassified as Parageobacillus galactosidasius comb. nov. and Parageobacillus yumthangensis comb. nov.

Antimicrobial Potential of the Genera Geobacillus and Parageobacillus, as Well as Endolysins Biosynthesized by Their Bacteriophages

“…Species belonging at the baseline of Geobacillus , which have been moved to Parageobacillus , include: P. caldoxylosilyticus , P. thermoglucosidasius , P. thermantarcticus , P. toebii and P. genomospecies 1 (NUB3621) [ 9 ]. Subsequently, in 2020, Najar and colleagues presented the analysis that supports their proposal of including two other species: G. galactosidasius and G. yumthangensis in the genus Parageobacillus [ 10 ].…”

Bacterial diversity, physicochemical and geothermometry of South Asian hot springs

“…These microbes are generally termed as thermophiles and they have great potential biotechnological and industrial applications depending on their enzymes. Novel bacterium Parageobacillus yumthangensis AYN2 was discovered and also various viruses, archaea and fungi has also been studied from the various hot springs of Sikkim ( Bhatia et al., 2015 ; Das and Thakur, 2020d ; Das et al., 2020b ; 2020c ; Das et al., 2021b ; Huang et al., 2011 ; Kumar et al., 2004 ; Najar et al., 2018a ; 2018b ; Najar et al., 2020a ; 2020c ; Pandey et al., 2014 ; Rawat and Joshi, 2018; Sharma et al., 2017 ).…”

Not All That Glitters Is Gold: The Paradox of CO-dependent Hydrogenogenesis in Parageobacillus thermoglucosidasius

“…Although they share many features, including growth temperature requirement (obligate thermophiles) with their closest relatives in the genus Geobacillus , Parageobacillus species are distinguished by a characteristic low genomic G + C content and a distinct phylogenetic clustering among several other phylogenomic features ( Aliyu et al, 2016 , 2018 ). At present, the genus comprises six species with taxonomic standing ( Najar et al, 2020 ), including the type species of the genus, Parageobacillus thermoglucosidasius ( Suzuki et al, 1983 ; Aliyu et al, 2016 ).…”