Published in:
Stand Genomic Sci 12 , 74 (Dec 5 2017)
Author(s):
DOI:
10.1186/s40793-017-0283-x
Abstract:
The type strain of the prospective 10.1601/nm.30737 sp. nov. ERR11(T), was isolated from a nodule of the leguminous tree Erythrina brucei native to Ethiopia. The type strain 10.1601/nm.1463 10.1601/strainfinder?urlappend=%3Fid%3DCCBAU+10071 (T), was isolated from the nodules of Lespedeza cuneata in Beijing, China. The genomes of ERR11(T) and 10.1601/strainfinder?urlappend=%3Fid%3DCCBAU+10071 (T) were sequenced by DOE-JGI and deposited at the DOE-JGI genome portal as well as at the European Nucleotide Archive. The genome of ERR11(T) is 9,163,226 bp in length and has 102 scaffolds, containing 8548 protein-coding and 86 RNA genes. The 10.1601/strainfinder?urlappend=%3Fid%3DCCBAU+10071 (T) genome is arranged in 108 scaffolds and consists of 8,201,522 bp long and 7776 protein-coding and 85 RNA genes. Both genomes contain symbiotic genes, which are homologous to the genes found in the complete genome sequence of 10.1601/nm.24498 10.1601/strainfinder?urlappend=%3Fid%3DUSDA+110 (T). The genes encoding for nodulation and nitrogen fixation in ERR11(T) showed high sequence similarity with homologous genes found in the draft genome of peanut-nodulating 10.1601/nm.27386 10.1601/strainfinder?urlappend=%3Fid%3DLMG+26795 (T). The nodulation genes nolYA-nodD2D1YABCSUIJ-nolO-nodZ of ERR11(T) and 10.1601/strainfinder?urlappend=%3Fid%3DCCBAU+10071 (T) are organized in a similar way to the homologous genes identified in the genomes of 10.1601/strainfinder?urlappend=%3Fid%3DUSDA+110 (T), 10.1601/nm.25806 10.1601/strainfinder?urlappend=%3Fid%3DUSDA+4 and 10.1601/nm.1462 10.1601/strainfinder?urlappend=%3Fid%3DCCBAU+05525. The genomes harbor hupSLCFHK and hypBFDE genes that code the expression of hydrogenase, an enzyme that helps rhizobia to uptake hydrogen released by the N2-fixation process and genes encoding denitrification functions napEDABC and norCBQD for nitrate and nitric oxide reduction, respectively. The genome of ERR11(T) also contains nosRZDFYLX genes encoding nitrous oxide reductase. Based on multilocus sequence analysis of housekeeping genes, the novel species, which contains eight strains formed a unique group close to the 10.1601/nm.25806 branch. Genome Average Nucleotide Identity (ANI) calculated between the genome sequences of ERR11(T) and closely related sequences revealed that strains belonging to 10.1601/nm.25806 branch (10.1601/strainfinder?urlappend=%3Fid%3DUSDA+4 and 10.1601/strainfinder?urlappend=%3Fid%3DCCBAU+15615), were the closest strains to the strain ERR11(T) with 95.2% ANI. Type strain ERR11(T) showed the highest DDH predicted value with 10.1601/strainfinder?urlappend=%3Fid%3DCCBAU+15615 (58.5%), followed by 10.1601/strainfinder?urlappend=%3Fid%3DUSDA+4 (53.1%). Nevertheless, the ANI and DDH values obtained between ERR11(T) and 10.1601/strainfinder?urlappend=%3Fid%3DCCBAU+15615 or 10.1601/strainfinder?urlappend=%3Fid%3DUSDA+4 were below the cutoff values (ANI >/= 96.5%; DDH >/= 70%) for strains belonging to the same species, suggesting that ERR11(T) is a new species. Therefore, based on the phylogenetic analysis, ANI and DDH values, we formally propose the creation of 10.1601/nm.30737 sp. nov. with strain ERR11(T) (10.1601/strainfinder?urlappend=%3Fid%3DHAMBI+3532 (T)=10.1601/strainfinder?urlappend=%3Fid%3DLMG+30162 (T)) as the type strain.