Cook Anthony R, Riley Paul W, Murdoch Heather, Evans Paul N, McDonald Ian R
Health Protection Agency, Centre for Emergency Preparedness and Response, Porton Down, Salisbury SP4 0JG, UK.
Rumen Biotechnology, AgResearch, Grasslands Research Centre, Private Bag 11008, Palmerston North 4442, New Zealand.
Int J Syst Evol Microbiol. 2007 Dec;57(Pt 12):2940-2945. doi: 10.1099/ijs.0.64819-0.
An unidentified obligately anaerobic, fastidious, Gram-positive, non-motile, non-spore-forming, non-fermentative coccoid-shaped bacterium (designated strain GPC 589(T)) was isolated from the rumen fluid of a sheep. The major fatty acid constituents (>5 %) were C(16 : 0) (29.2 %), C(18 : 0) (40.7 %) and an unidentified compound (19.7 %) with an equivalent chain-length of 13.523. The G+C content of the DNA was 34 mol%. The organism was strongly ureolytic and generated ATP through the hydrolysis of urea. Comparative 16S rRNA gene sequence analysis demonstrated that strain GPC 589(T) was far removed, phylogenetically, from the ruminococci and related Gram-positive anaerobic cocci but exhibited a phylogenetic association with Clostridium rRNA cluster XIVa [as defined by Collins, M. D., Lawson, P. A., Willems, A., Cordoba, J. J., Fernandez-Garayzabal, J., Garcia, P., Cai, J., Hippe, H. & Farrow, J. A. E. (1994). Int J Syst Bacteriol 44, 812-826]. Sequence divergence values of 12.5 % or more were observed between strain GPC 589(T) and all other recognized species within this and related rRNA clostridial clusters. Phylogenetic analysis showed that strain GPC 589(T) represents a new genus within cluster XIVa. On the basis of both phylogenetic and phenotypic evidence, it is proposed that strain GPC 589(T) should be classified as representing a new genus and novel species, Howardella ureilytica gen. nov., sp. nov. The type strain is strain GPC 589(T) (=DSM 15118(T)=JCM 13267(T)).
从一只绵羊的瘤胃液中分离出一株未鉴定的专性厌氧、苛求、革兰氏阳性、不运动、不产芽孢、非发酵的球状细菌（命名为菌株GPC 589(T)）。主要脂肪酸成分（>5%）为C(16 : 0)（29.2%）、C(18 : 0)（40.7%）和一种等效链长为13.523的未鉴定化合物（19.7%）。DNA的G+C含量为34 mol%。该菌具有强烈的尿素分解能力，通过尿素水解产生ATP。比较16S rRNA基因序列分析表明，菌株GPC 589(T)在系统发育上与瘤胃球菌及相关革兰氏阳性厌氧球菌差异很大，但与梭菌属rRNA簇XIVa（如Collins, M. D., Lawson, P. A., Willems, A., Cordoba, J. J., Fernandez-Garayzabal, J., Garcia, P., Cai, J., Hippe, H. & Farrow, J. A. E. (1994). Int J Syst Bacteriol 44, 812 - 826所定义）存在系统发育关联。在该簇及相关梭菌属rRNA簇内，菌株GPC 589(T)与所有其他已确认的物种之间的序列差异值均在12.5%或以上。系统发育分析表明，菌株GPC 589(T)代表簇XIVa内的一个新属。基于系统发育和表型证据，建议将菌株GPC 589(T)分类为一个新属和新物种，即解脲霍华德菌属（Howardella ureilytica），新属，新种。模式菌株为菌株GPC 589(T)（=DSM 15118(T)=JCM 13267(T)）。
