Shieh Wung Yang, Lin Yu-Te, Jean Wen Dar
Institute of Oceanography, National Taiwan University, PO Box 23-13, Taipei, Taiwan.
Center for General Education, Leader University, No. 188, Sec. 5, An-Chung Rd, Tainan, Taiwan.
Int J Syst Evol Microbiol. 2004 Nov;54(Pt 6):2307-2312. doi: 10.1099/ijs.0.63107-0.
Two denitrifying strains of heterotrophic, facultatively anaerobic, marine bacteria, designated DN34(T) and DN33, were isolated from sea-water samples collected in Nanwan Bay, Kenting National Park, Taiwan. They were Gram-negative. Cells in late exponential to early stationary phase of growth were predominantly straight or curved rods, but Y- or V-shaped forms were also observed. They were motile by means of one to several lateral or subpolar flagella. Both strains required NaCl for growth and exhibited optimal growth at about 30 degrees C, pH 8 and 3 % NaCl. They were capable of anaerobic growth by carrying out denitrifying metabolism using nitrate, nitrite or nitrous oxide as terminal electron acceptors or, alternatively, by fermenting glucose, mannose, sucrose or trehalose as substrates. Anaerobic fermentative growth on glucose resulted in formation of various organic acids, including formate, lactate, acetate, pyruvate and fumarate. The major cellular fatty acids were 2-OH-14 : 0, 3-OH-14 : 0 and 16 : 0. DN34(T) and DN33 had DNA G+C contents of 51.7 and 51.6 mol%, respectively. Physiological characterization, together with phylogenetic analysis based on 16S rRNA gene sequence analysis, revealed that the two denitrifying strains could be accommodated in a novel genus, for which the name Pseudovibrio gen. nov. is proposed. Pseudovibrio denitrificans sp. nov. is the type species, with DN34(T) (=BCRC 17323(T)=JCM 12308(T)) as the type strain.
从台湾垦丁国家公园南湾湾采集的海水样本中分离出两株异化型、兼性厌氧的海洋反硝化细菌菌株，分别命名为DN34(T)和DN33。它们为革兰氏阴性菌。处于生长对数后期至稳定期早期的细胞主要为直杆状或弯曲杆状，但也观察到Y形或V形形态。它们通过一至数根侧生或亚极生鞭毛运动。两株菌株的生长均需要NaCl，在约30℃、pH 8和3% NaCl条件下生长最佳。它们能够以硝酸盐、亚硝酸盐或一氧化二氮作为末端电子受体进行反硝化代谢，或者以葡萄糖、甘露糖、蔗糖或海藻糖为底物进行发酵，从而进行厌氧生长。在葡萄糖上进行厌氧发酵生长会产生多种有机酸，包括甲酸、乳酸、乙酸、丙酮酸和富马酸。主要细胞脂肪酸为2-OH-14 : 0、3-OH-14 : 0和16 : 0。DN34(T)和DN33的DNA G+C含量分别为51.7 mol%和51.6 mol%。生理特征以及基于16S rRNA基因序列分析的系统发育分析表明，这两株反硝化菌株可归入一个新属，为此提议命名为Pseudovibrio gen. nov.。反硝化假弧菌（Pseudovibrio denitrificans sp. nov.）为模式种，以DN34(T)（=BCRC 17323(T)=JCM 12308(T)）作为模式菌株。
