Fernández-Martínez Javier, Pujalte María J, García-Martínez Jesús, Mata Manuel, Garay Esperanza, Rodríguez-Valera Francisco
División de Microbiología, Universidad Miguel Hernández, Campus de San Juan, Ctra. de Valencia km 87, 03550 San Juan, Alicante, Spain.
Instituto Cavanilles de Biodiversidad y Biologia Evolutiva, Universitat de València, Spain.
Int J Syst Evol Microbiol. 2003 Jan;53(Pt 1):331-338. doi: 10.1099/ijs.0.01923-0.
Two strains of a novel bacterium were isolated independently of each other, from different depths in the Mediterranean Sea, within a time period of 7 months, using two different isolation approaches that were focused on different objectives. Both strains, designated ISO1 and ISO4T, were halophilic, Gram-negative, strictly aerobic, straight rods that were oxidase- and catalase-positive. Both strains produced mucoid colonies in some defined minimal media and were able to grow with organic acids and some alkanes; they were also able to accumulate intracellular poly-beta-hydroxybutyrate granules. The G + C content of the DNA of strain ISO4T was 66 mol%. Comparative analysis of 16S rRNA gene sequences showed that the closest described species to the novel strains were Alcanivorax borkumensis and Fundibacter jadensis, both of the gamma-Proteobacteria. Both of these recognized species were originally isolated from North Sea waters and are able to degrade aliphatic compounds, a property shared with strains ISO1 and ISO4T. However, strains ISO1 and ISO4T were different from A. borkumensis and F. jadensis, not only in their 16S rDNA sequences but also in the motility of their cells (by polar flagella) and by the presence of C19:Ocyclo in their cellular fatty acids, among other differential features. On the basis of biochemical and molecular data, it is suggested that strains ISO1 and ISO4T be recognized as a novel species of the genus Alcanivorax, for which the name Alcanivorax venustensis (ISO4T =DSM 13974T =CECT 5388T) is proposed. On the basis of its high phenotypic similarity and close phylogenetic relatedness to A. borkumensis, it is also proposed that F. jadensis (DSM 12178T) be reclassified as Alcanivorax jadensis in the genus Alcanivorax, and that the description of the genus Alcanivorax be emended.
在7个月的时间内，利用两种针对不同目标的不同分离方法，从地中海不同深度彼此独立地分离出两株新型细菌。这两株菌分别命名为ISO1和ISO4T，均为嗜盐、革兰氏阴性、严格需氧的直杆菌，氧化酶和过氧化氢酶呈阳性。两株菌在某些特定的基本培养基中都能产生黏液状菌落，并且能够利用有机酸和一些烷烃生长；它们还能够积累细胞内聚-β-羟基丁酸酯颗粒。菌株ISO4T的DNA的G + C含量为66 mol%。16S rRNA基因序列的比较分析表明，与这两株新型菌株亲缘关系最近的已知物种是嗜油栖热袍菌和牙本质杆菌，它们都属于γ-变形菌纲。这两个已知物种最初都是从北海海域分离出来的，并且都能够降解脂肪族化合物，这一特性与菌株ISO1和ISO4T相同。然而，菌株ISO1和ISO4T与嗜油栖热袍菌和牙本质杆菌不同，不仅在16S rDNA序列上不同，而且在细胞运动性（通过极生鞭毛）以及细胞脂肪酸中存在C19:O环等其他差异特征方面也不同。根据生化和分子数据，建议将菌株ISO1和ISO4T认定为嗜油栖热袍菌属的一个新物种，为此提出了嗜油栖热袍菌（Alcanivorax venustensis）的名称（ISO4T =DSM 13974T =CECT 5388T）。基于其与嗜油栖热袍菌的高度表型相似性和紧密的系统发育相关性，还建议将牙本质杆菌（DSM 12178T）重新分类为嗜油栖热袍菌属的牙本质嗜油栖热袍菌，并对嗜油栖热袍菌属的描述进行修订。
