Nocardia veterana sp. nov., isolated from human bronchial lavage

Abstract

A nocardioform bacterium was isolated from the bronchoscopic lavage of a 78-year-old man with a past history of tuberculous pleurisy, who presented with bilateral upper lobe lesions at Austin and Repatriation Medical Centre, Heidelberg, Australia. The strain was aerobic, Gram-positive, produced beige substrate mycelium and scant white aerial mycelium. It showed chemotaxonomic markers which were consistent with the classification of Nocardia: i.e. meso-diaminopimelic acid, N-glycolylmuramic acid, arabinose and galactose as diagnostic sugars; phospholipids phosphatidylinositol mannosides, phosphatidylinositol, phosphatidylethanolamine and diphosphatidylglycerol; a menaquinone with a cyclic isoprene side chain, MK-8(H4cycl.); a fatty acid pattern composed of unbranched saturated and monounsaturated fatty acids with a considerable amount of tuberculostearic acid; and mycolic acids composed of 54-62 carbon atoms with three principal mycolic acids which were mono- and polyunsaturated, showing a chain length C56, C58 and C60 and accounting for over 70% of the entire pattern. The 16S rDNA sequence showed the highest similarity to the type strain of Nocardia vaccinii; the DNA-DNA similarity of the two strains was 31%. These data, together with distinct physiological traits and molecular biological analyses, as well as chemotaxonomic results, led to the conclusion that the novel isolate represents a new species within the genus Nocardia for which the name Nocardia veterana sp. nov. is proposed. The type strain is M157222T (DSM 44445T = NRRL B-24136T).