Nocardia shinanonensis sp. nov., isolated from a patient with endophthalmitis

A nocardioform strain IFM 11456T was isolated from the aqueous humor from a patient with endophthalmitis and was characterized to its taxonomic position. IFM 11456T contained arabinose, galactose and meso-diaminopimelic acid in whole-cell hydrolysates and mycolic acids that co-migrated with those from the type strain of Nocardiaasteroides. The acyl type of muramic acid was N-glycolyl. The diagnostic polar lipids were phosphatidylethanolamine, diphosphatidylglycerol and two unidentified glycolipids and the predominant menaquinone was MK-8(H4, ω-cycl.). These characteristics are typical of members of the genus Nocardia. Results of phylogenetic analyses based on 16S rRNA gene sequences indicated that the isolate represented a novel species of the genus Nocardia and was most closely related to the type strains of Nocardia mikamii JCM 15508T (98.1 %) and Nocardiaaobensis IFM 0372T (98.1 %). However, analysis of partial gyrB sequences showed that strain IFM 11456T had 90.2 % similarity to Nocardia concava IFM 0354T and 90 % to Nocardianiigatensis IFM 0330T. The DNA-DNA relatedness values for strain IFM 11456T compared with N. mikamii JCM 15508T, N. aobensisIFM 0372T and N. concava IFM 0354T ranged from 24.4 to 39.9 %. Phenotypic characteristics that differentiated IFM 11456T from phylogenetically related species were growth at 45 °C, utilization of citrate and growth with inositol as a sole carbon source. On the basis of this polyphasic study, the isolate represents a novel species within the genus Nocardia, for which the name Nocardia shinanonensis sp. nov. is proposed. The type strain is IFM 11456T (=NBRC 109590T=TBRC 5149T).