Table_1_Antibiotic Modulation of Capsular Exopolysaccharide in Pelagicoccus enzymogenes sp. nov. Isolated From Marine Sediment.XLSX

Although Verrucomicrobia is widely distributed in the marine environment, their physiological or cellular properties are poorly characterized because of the lack of cultured representatives. Under the selective pressure of two antibiotics, ofloxacin and norfloxacin, a Gram-stain-negative, aerobic coccus with exopolysaccharide (EPS) production ability was isolated from the coastal sediment of Xiaoshi Island, Weihai, China. These antibiotics inhibited bacterial growth, giving rise to the relatively slow-growing Verrucomicrobia that formed colonies on the isolation plates. It may be an effective method for the isolation of Puniceicoccaceae. From the taxonomic data obtained in this study, the new marine isolate NFK12T (=KCTC 72940T = MCCC 1H00424T) is proposed to be placed into a novel species within the genus Pelagicoccus for which the name Pelagicoccus enzymogenes sp. nov. is proposed. The EPS production of the strain NFK12T and the related strains were investigated and the effect of EPS produced by the strain NFK12T on the growth of other strains was examined. Besides, the effect of EPS on tolerance to ofloxacin and norfloxacin of the strain NFK12T was studied by measuring the biomass of the strain NFK12T. It was deduced that those strains that produced EPS tentatively protected themselves against the inhibitory effects of ofloxacin and norfloxacin.

尽管疣微菌在海洋环境中广泛分布，但由于缺乏已培养的代表性菌株，其生理或细胞特性描述尚不充分。在两种抗生素，氧氟沙星和诺氟沙星的筛选压力下，从我国威海市小石岛沿岸沉积物中分离出了一种不染色的需氧球菌，该菌株具有外多糖（EPS）的生成能力。这两种抗生素抑制了细菌的生长，从而形成了在分离平板上生长较慢的疣微菌菌落。这可能是一种分离红球菌科的有效方法。本研究获得分类学数据表明，新分离的海洋菌株NFK12T（=KCTC 72940T = MCCC 1H00424T）被提议归类于Pelagicoccus属内的一个新物种，并为该物种提出了Pelagicoccus enzymogenes sp. nov.这一名称。对菌株NFK12T及其相关菌株的EPS生成能力进行了研究，并考察了由NFK12T菌株产生的EPS对其他菌株生长的影响。此外，通过测量菌株NFK12T的生物量，研究了EPS对菌株NFK12T耐受氧氟沙星和诺氟沙星的影响。据此推断，那些产生EPS的菌株可能通过保护性机制来抵御氧氟沙星和诺氟沙星的抑制作用。