Sattley W Matthew, Jung Deborah O, Madigan Michael T
Department of Microbiology, Southern Illinois University, Carbondale, IL, USA.
FEMS Microbiol Lett. 2008 Oct;287(1):121-7. doi: 10.1111/j.1574-6968.2008.01300.x. Epub 2008 Jul 30.
A novel, obligately anaerobic, fermentative bacterium, strain FCF9, was isolated from a 9-m water sample from permanently ice-covered, meromictic Lake Fryxell, Antarctica. A phylogenetic analysis based on 16S rRNA gene sequence identity clustered the Antarctic isolate within the Sporomusa-Pectinatus-Selenomonas phyletic group, where it was most closely related to Pelosinus fermentans (95.5% sequence identity). However, unlike species of Pelosinus, strain FCF9 was psychrophilic, with growth occurring optimally near 15 degrees C, and endospores were not produced. The metabolism of the new organism was strictly fermentative. The substrates fermented by strain FCF9 included only lactate and a few related organic acids. The major products from lactate fermentation were acetate and propionate. On the basis of phylogenetic, morphological, and physiological criteria, strain FCF9(T) is proposed as the type strain of a novel genus and species of psychrophilic-fermenting bacteria, Psychrosinus fermentans gen. nov., sp. nov.
从南极永久冰封的分层湖弗里克塞尔湖9米深处的水样中分离出一种新型专性厌氧发酵细菌FCF9菌株。基于16S rRNA基因序列同一性的系统发育分析将该南极分离株聚类到梭形芽孢杆菌-果胶杆菌-月形单胞菌系统发育组中，它与发酵泥杆菌关系最为密切（序列同一性为95.5%）。然而，与泥杆菌属的物种不同，FCF9菌株是嗜冷菌，在15℃左右生长最佳，且不产生内生孢子。这种新生物体的代谢严格为发酵型。FCF9菌株发酵的底物仅包括乳酸和少数相关有机酸。乳酸发酵的主要产物是乙酸盐和丙酸盐。基于系统发育、形态学和生理学标准，提议将FCF9(T)菌株作为嗜冷发酵细菌新属新种的模式菌株，即嗜冷发酵菌属（Psychrosinus），发酵嗜冷菌（Psychrosinus fermentans）。
