A Gram-stain-positive, non-spore-forming bacterium (GW5-5797T) was isolated on soil extract
agar from sand collected at a depth of 5 m in the Caribbean Sea near Grenada. 16S rRNA gene
sequence analysis and similarity studies showed that strain GW5-5797T belongs to the genus
Nocardia, and is most closely related to Nocardia speluncae N2-11T (99.2% similarity) and
Nocardia jinanensis 04-5195T (99.2 %) and more distantly related to Nocardia rhamnosiphila
202GMOT (98.6 %) and other Nocardia species. Strain GW5-5797T could be distinguished from
all other recognized Nocardia species by sequence similarity values less than 98.5 %. The
peptidoglycan diamino acid was meso-diaminopimelic acid. Strain GW5-5797T exhibited a
quinone system with the predominant compounds MK-8(H4v-cyclo) and MK-8(H2). The polar
lipid profile of GW5-5797T consisted of the major compounds diphosphatidylglycerol,
phosphatidylethanolamine and an unidentified glycolipid, moderate amounts of
phosphatidylinositol and a phosphatidylinositol mannoside and minor amounts of several lipids
including a second phosphatidylinositol mannoside. The polyamine pattern contained the major
compound spermine and moderate amounts of spermidine. The major fatty acids were C16 : 0,
C18 : 1v9c and 10-methyl C18 : 0. These chemotaxonomic traits are in excellent agreement with
those of other Nocardia species. The results of DNA–DNA hybridizations and physiological and
biochemical tests allowed genotypic and phenotypic differentiation of strain GW5-5797T from the
most closely related species, showing 16S rRNA gene sequence similarities .98.5 %. Strain
GW5-5797T therefore merits separate species status, and we propose the name Nocardia
grenadensis sp. nov., with the type strain GW5-5797T (5CCUG 60970T 5CIP 110294T).