Streptomyces lasalocidi sp. nov. (formerly ‘Streptomyces lasaliensis’), an actinomycete isolated from soil which produces the polyether antibiotic lasalocid

Abstract

Strain ATCC 31180^T was isolated from soil collected in Hyde Park, Massachusetts (USA), and found to produce the polyether antibiotic lasalocid. The name '<i>Streptomyces lasaliensis</i>' has been in common use since 1974, without a recognized taxonomic description. The most closely related type cultures determined by rRNA gene sequence similarity were <i>Streptomyces longwoodensis</i> DSM 41677^T (100 %) and <i>Streptomyces galbus</i> DSM 40089^T (100 %). OrthoANI values with <i>S. longwoodensis</i> and <i>S. galbus</i> were 95.50 and 94.41 %, respectively. Chemotaxonomic characteristics supported inclusion within the genus <i>Streptomyces</i>. The cell wall peptidoglycan contained ll-diaminopimelic acid, and the major whole-cell sugars were glucose and ribose. Polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol, phosphatidylglycerol, one unidentified lipid and one unidentified glycolipid. The major menaquinones detected were MK9(H₄), MK9(H₆) and MK9(H₈). The major cellular fatty acids were anteiso<i>-</i>C_{15 : 0}, anteiso<i>-</i>C_{17 : 0}, iso<i>-</i>C_{16 : 0}, iso<i>-</i>C_{15 : 0} and anteiso<i>-</i>C_{17 : 1}. Its DNA had a G+C content of 72.6 %. Differentiation of ATCC 31180^T from the closely related species was evident from digital DNA-DNA hybridization values of 61.80 and 56.90 % for <i>S. longwoodensis</i> and <i>S. galbus</i> respectively. Significant differences were seen in the polyphasic phenotypic analyses. ATCC 31180^T produced lasalocid, grew from 10 to 45 °C, pH4-8 and in the presence of 0-10 % NaCl, 0.01 % NaN₃ and 1 % phenol. Melanin was produced; H₂S and indole were not. Nitrate was not reduced. Spore chains were retinaculum-apertum and spore surfaces were smooth. Spore colour, mycelia colour and soluble pigment production were medium-dependent. The proposed name is <i>Streptomyces lasalocidi</i> sp. nov.; the type strain being ATCC 31180^T (=NRRL 3382^T=DSM 46487^T).