A Gram-positive, aerobic, non-motile, irregular short rod, nonspore-forming actinobacterial strain, designated GX14115T, was isolated from fish intestine in Beihai City, Guangxi, China and subjected to a taxonomic polyphasic investigation. Colonies were yellow‒green, circular, smooth, central bulge, convex, opaque and 2.0-3.0 mm in diameter after growth on 2216E medium at 30 °C for 72 h. Growth occurred at 4-45 °C (optimum 30 °C), at pH 4.5-10.0 (optimum pH 7.5) and in the presence of 0-12% NaCl (w/v) (optimum 3.5%). Chemotaxonomic analysis showed that the main menaquinone of strain GX14115T was MK-7. The major cellular fatty acids were anteiso-C15:0 (44.8%), anteiso-C17:0 (20.5%), and iso-C15:0 (16%). The whole-cell sugars were galactose and xylose. The peptidoglycan type was L-Lys-Gly-D-Asp, and the polar lipids were phosphatidylethanolamine (PE), diphosphatidylglycerol (DPG), one unknown phospholipid (UP), and one unknown glycolipid (UG). The DNA G + C content of the type of strain was 69.5 mol%. The 16S rRNA gene sequence analysis revealed that strain GX14115T is affiliated with the genus Nesterenkonia and is closely related to Nesterenkonia sandarakina YIM 70009T (96.5%) and Nesterenkonia lutea YIM 70081T (96.8%). The calculated results indicated that the average nucleotide identity (ANI) values of GX14115T were 74.49-74.78%, to the two aforementioned type strains, and the digital DNA-DNA hybridization (dDDH) values were 20.1-20.7%. Strain GX14115T was proposed as a novel species of the genus Nesterenkonia by the physiological, chemotaxonomic, and phylogenetic data, for whose the name is Nesterenkonia marinintestina sp. nov. The type of strain is GX14115T (= MCCC 1K06658T = KCTC 49495T).
Keywords: Actinomycetes; Fish intestinal; Marine fishes; Novel species.
© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.