Main content area

Nocardiopsis mwathae sp. nov., isolated from the haloalkaline Lake Elmenteita in the African Rift Valley

Akhwale, Juliah Khayeli, Göker, Markus, Rohde, Manfred, Schumann, Peter, Boga, Hamadi Iddi, Klenk, Hans-Peter
Antonie van Leeuwenhoek 2016 v.109 no.3 pp. 421-430
DNA, Nocardiopsis, bacteria, fatty acids, lakes, menaquinones, mycelium, new species, nucleotide sequences, pH, peptidoglycans, phosphatidylcholines, ribosomal RNA, screening, sediments, sequence homology, sugars
During a screening for novel and biotechnologically useful bacteria in haloalkaline lakes, strain No.156ᵀ was isolated from a sediment sample from lake Elmenteita in the African Rift Valley and studied by a polyphasic taxonomic approach. The strain was observed to form yellow aerial and substrate mycelia; optimal growth was found to be at 30–35 °C in salt concentrations of 6–9 % (w/v) and at pH 7–9. The DNA G+C content of the novel strain was 71 mol%. Analysis of 16S rRNA sequences indicated that the isolate belongs to the genus Nocardiopsis with sequence similarities below 98 % to the type strains of all other representatives of the genus. Mycolic acids were not detected in whole cell methanolysates. The peptidoglycan was found to contain meso-diaminopimelic acid as the diamino acid with no diagnostic sugars. The main polar lipids were identified as phosphatidylmethylethanolamine, phosphatidylcholine, phosphatidylglycerol and phosphatidylinositol but no diphosphatidylglycerol. The predominant menaquinones were MK-11(H₈), MK-11(H₆), MK-10(H₈) and MK-10(H₆). Cellular fatty acids were found to consist of saturated and monounsaturated iso- and anteiso-branched acids with 16–18 C-length, tuberculostearic acid (Me18:0), and straight-chain saturated (16:0, 18:0) acids. These characteristics match those of the genus Nocardiopsis. Based on 16S rRNA gene sequence analysis and phenotypic characteristics, a novel species with the name Nocardiopsis mwathae is proposed. The type strain is No.156ᵀ (=DSM 46659ᵀ = CECT 8552ᵀ). The INSDC accession number for the 16S rRNA gene sequence of strain No.156ᵀ is KF976731.