03286naa a2200433 a 450000100080000000500110000800800410001902200140006010000190007424501230009326000090021652020400022565000120226565000220227765000290229965000140232865000220234265300270236465300270239165300130241865300330243165300260246465300230249070000240251370000150253770000160255270000240256870000240259270000230261670000130263970000190265270000230267170000200269470000170271470000170273170000300274870000170277877300570279521668572024-08-28       2024    bl uuuu     u00u1 u    #d  a1432-09911 aBALDANI, J. I.  aNitrospirillum viridazoti sp. nov., an efficient nitrogen-fixing species Isolated from grasses.h[electronic resource]  c2024  aA group of Gram-negative plant-associated diazotrophic bacteria belonging to the genus Nitrospirillum was investigated,including both previously characterized and newly isolated strains from diverse regions and biomes, predominantly in Brazil. Phylogenetic analysis of 16S rRNA and recA genes revealed the formation of a distinct clade consisting of thirteen strains, separate from the formally recognized species N. amazonense (the closest species) and N. iridis. Comprehensive taxonomic analyses using the whole genomes of four strains (BR 11140T=AM 18T=Y-2T=DSM 2788T=ATCC 35120T, BR 11142T=AM 14T=Y-1T=DSM 2787T=ATCC 35119T, BR 11145=CBAmC, and BR 12005) supported the division of these strains into two species: N. amazonense (BR 11142 T and BR 12005) and a newly proposed species (BR 11140 T and BR 11145), distinct from N. iridis. The phylogenomic analysis further confrmed the presence of the new Nitrospirillum species. Additionally, MALDI-TOF MS analysis of whole-cell mass spectra provided further evidence for the diferentiation of the proposed Nitrospirillum species, separate from N. amazonense. Analysis of chemotaxonomy markers (i.e., genes involved in fatty acid synthesis, metabolism and elongation, phospholipid synthesis, and quinone synthesis) revealed that the new species highlights high similarity and evolutionary convergence with other Nitrospirillum species. This new species exhibited nitrogen fxation ability in vitro, it has similar NifHDK protein phylogeny position with the closest species, lacked denitrifcation capability, but possessed the nosZ gene, enabling N2O reduction, distinguishing it from the closest species. Despite being isolated from diverse geographic regions, soil types, and ecological niches, no signifcant phenotypic or physiological diferences were observed between the proposed new species and N. amazonense. Based on these fndings, a new species, Nitrospirillum viridazoti sp. nov., was classifed, with the strain BR 11140T (DSM 2788T, ATCC 35120T) designated as the type strain.  aGrasses  aNitrogen fixation  aFixação de Nitrogênio  aGramínea  aTaxonomia Vegetal  aAnálise filogenética  aAnálises taxonômicas  aBR 11140  aNitrospirillum viridazoti sp  aPhylogenetic analysis  aTaxonomic analyses1 aFERREIRA, N. dos S.1 aSCHWAB, S.1 aREIS, V. M.1 aSOARES, L. H. de B.1 aARAUJO, J. L. S. de1 aDOURADO, F. dos S.1 aBACH, e.1 aCAMACHO, N. N.1 aOLIVEIRA, A. M. de1 aALVES, B. J. R.1 aSILVA, A. L.1 aROSSI, C. N.1 aOLIVEIRA JUNIOR, A. F. de1 aZILLI, J. E.  tCurrent Microbiologygv. 81, n. 6, p. 144-166, 2024.