Nocardia arizonensis sp. nov., obtained from human respiratory specimens

Updated Review on Nocardia Species: 2006-2021

This review serves as an update to the previous Nocardia review by Brown-Elliott et al. published in 2006 (B. A. Brown-Elliott, J. M. Brown, P. S. Conville, and R. J. Wallace. Jr., Clin Microbiol Rev 19:259-282, 2006, https://doi.org/10.1128/CMR.19.2.259-282.2006). Included is a discussion on the taxonomic expansion of the genus, current identification methods, and the impact of new technology (including matrix-assisted laser desorption ionization-time of flight [MALDI-TOF] and whole genome sequencing) on diagnosis and treatment. Clinical manifestations, the epidemiology, and geographic distribution are briefly discussed. An additional section on actinomycotic mycetoma is added to address this often-neglected disease.

Nocardia albiluteola sp. nov., a novel lignin-degrading actinobacterium isolated from rhizosphere soil of pumpkin

A novel lignin-degrading actinobacterium, designated NEAU-G5T, was isolated from pumpkin rhizosphere soil collected from field in Mudanjiang, Heilongjiang Province, northeast China, and characterized using polyphasic approach. The prior 16S rRNA gene sequence similarities and phylogenic analysis showed that strain NEAU-G5T exhibited close phylogenetic relatedness to Nocardia miyunensis NBRC 108239T (98.82 %), Nocardia nova NBRC 15556T (98.75 %), Nocardia jiangxiensis NBRC 101359T (98.68 %) and Nocardia macrotermitis RB20T (98.61 %). Morphological and chemotaxonomic characteristics indicated that strain NEAU-G5T could be assigned to the genus Nocardia . The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, an unidentified phospholipid and an unidentified lipid. The predominant menaquinone was MK-8(H4, ω-cycl). The major fatty acids (>10 %) were identified as C16 : 0, C18 : 1  ω9c, 10-methyl C18 : 0 and C18 : 0. Mycolic acids were present. The genomic DNA G+C content of strain NEAU-G5T was 68 mol%. Moreover, based on digital DNA–DNA hybridization and average nucleotide identity values, strain NEAU-G5T could be differentiated from its reference strains. In addition, an azure B plate decolorization test and genomic analysis indicated that strain NEAU-G5T had the ability to degrade lignin. On the basis of polyphasic characteristics, strain NEAU-G5T represents a novel species of the genus Nocardia , with the name Nocardia albiluteola sp. nov. The type strain is NEAU-G5T (=CCTCC AA 2021018T=DSM 110547T).

Nocardia bovistercoris sp. nov., an actinobacterium isolated from cow dung

A novel actinobacterium, designated strain NEAU-351^T, was isolated from cow dung collected from Shangzhi, Heilongjiang Province, northeast PR China and characterized using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain NEAU-351^T belonged to the genus Nocardia, with the highest similarity (98.96 %) to Nocardia takedensis DSM 44801^T and less than 98.0 % identity with other type strains of the genus Nocardia. The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. The major menaquinone was observed to contain MK-8(H₄, ω-cycl) (78.2 %). The fatty acid profile mainly consisted of C_16 : 0, C_18 : 1  ω9c and 10-methyl C_18 : 0. Mycolic acids were present. The genomic DNA G+C content of strain NEAU-351^T was 68.1 mol%. In addition, the average nucleotide identity values between strain NEAU-351^T and its reference strains, Nocardia takedensis DSM 44801^T and Nocardia arizonensis NBRC 108935^T, were found to be 81.4 and 82.9 %, respectively, and the level of digital DNA-DNA hybridization between them were 24.8 % (22.5-27.3 %) and 26.3 % (24-28.8 %), respectively. Here we report on the taxonomic characterization and classification of the isolate and propose that strain NEAU-351^T represents a new species of the genus Nocardia, for which the name Nocardia bovistercoris is proposed. The type strain is NEAU-351^T (=CCTCC AA 2019090^T=DSM 110681^T).

Nocardiosis from 1888 to 2017

The genus Nocardia is an aerobic bacterium, Gram-positive and catalase positive that is in Nocardiaceae family. This bacterium first described by Edmond Nocard in 1888 and is not in human commensal bacteria. To date, nocardiosis incidence is increasing due to increase population growth rate, increase in patients with immune disorder diseases and immunocompromised patients. We surveyed taxonomic position, isolation methods, phenotypic and molecular identification at the genus and species levels, antibiogram, treatment and epidemiology in the world from 1888 to 2017.