Sonnenschein Eva Christina, Phippen Christopher Broughton William, Nielsen Kristian Fog, Mateiu Ramona Valentina, Melchiorsen Jette, Gram Lone, Overmann Jörg, Freese Heike M
Department of Biotechnology and Biomedicine, Technical University of Denmark, Matematiktorvet 301, 2800 Kgs Lyngby, Denmark.
Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltoft Plads 221, 2800 Kgs Lyngby, Denmark.
Int J Syst Evol Microbiol. 2017 Nov;67(11):4559-4564. doi: 10.1099/ijsem.0.002331. Epub 2017 Oct 6.
Four heterotrophic, antimicrobial, motile, marine bacterial strains, 27-4, 8-1, M6-4.2 and S26, were isolated from aquaculture units in Spain, Denmark and Greece. All four strains produced the antibiotic compound tropodithietic acid, which is a key molecule in their antagonism against fish pathogenic bacteria. Cells of the strains were Gram-reaction-negative, rod-shaped and formed star-shaped aggregates in liquid culture and brown-coloured colonies on marine agar. The predominant cellular fatty acids were C18 : 1ω7c, C16 : 0, C11 methyl C18 : 1ω7c and C16 : 0 2-OH, and the polar lipids comprised phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, an aminolipid, a phospholipid and an unidentified lipid. The strains grew optimally at 31-33 °C. Growth was observed at a salt concentration between 0.5 and 5-6 % NaCl with an optimum at 2-3 %. The pH range for growth of the strains was from pH 6 to 8-8.5 with an optimum at pH 7. Based on 16S rRNA gene sequence analysis, the strains are affiliated with the genus Phaeobacter. The genome sequences of the strains have a DNA G+C content of 60.1 % and share an average nucleotide identity (ANI) of more than 95 %. The four strains are distinct from the type strains of the closely related species Phaeobactergallaeciensis and Phaeobacterinhibens based on an ANI of 90.5-91.7 and 89.6-90.4 %, respectively, and an in silico DNA-DNA hybridization relatedness of 43.9-46.9 and 39.8-41.9 %, respectively. On the basis of phylogenetic analyses as well as phenotypic and chemotaxonomic properties, the isolates are considered to represent a novel species, for which the name Phaeobacter piscinae sp. nov. is proposed. The type strain is 27-4 (=DSM 103509=LMG 29708).
从西班牙、丹麦和希腊的水产养殖单位中分离出了四株异养、具有抗菌性、能运动的海洋细菌菌株，分别为27-4、8-1、M6-4.2和S26。这四株菌株均产生抗生素化合物 tropodithietic acid，它是这些菌株对抗鱼类病原菌的关键分子。这些菌株的细胞革兰氏反应呈阴性，为杆状，在液体培养中形成星形聚集体，在海洋琼脂上形成褐色菌落。主要的细胞脂肪酸为C18 : 1ω7c、C16 : 0、C11甲基C18 : 1ω7c和C16 : 0 2-OH，极性脂质包括磷脂酰甘油、双磷脂酰甘油、磷脂酰乙醇胺、磷脂酰胆碱、一种氨基脂质、一种磷脂和一种未鉴定的脂质。这些菌株在31-33 °C时生长最佳。在盐浓度为0.5%至5-6 % NaCl之间观察到生长，最适盐浓度为2-3 %。这些菌株的生长pH范围为pH 6至8-8.5，最适pH为7。基于16S rRNA基因序列分析，这些菌株隶属于Phaeobacter属。这些菌株的基因组序列的DNA G+C含量为60.1 %，平均核苷酸同一性（ANI）超过95 %。基于ANI分别为90.5-91.7 %和89.6-90.4 %，以及基于计算机模拟的DNA-DNA杂交相关性分别为43.9-46.9 %和39.8-41.9 %，这四株菌株与密切相关物种Phaeobacter gallaeciensis和Phaeobacter inhibens的模式菌株不同。基于系统发育分析以及表型和化学分类学特性，这些分离株被认为代表一个新物种，为此提出名称Phaeobacter piscinae sp. nov.。模式菌株为27-4（=DSM 103509=LMG 29708）。
