PROPOSAL OF QUINELLA-OVALIS GEN-NOV, SP-NOV, BASED ON PHYLOGENETIC ANALYSIS

Quin's oval is a relatively large bacterium often seen in the rumens o f sheep fed diets containing some readily fermented carbohydrates. It has not been obtained in axenic cultures, but a number of its features have been determined by various methods, such as studying cell suspen sions purified from rumen fluid by differential centrifugation. We obt ained similarly purified suspensions from a sheep fed a diet containin g a large amount of molasses. Nearly complete 16S rRNA sequence analys is of these cells as well as cells of Selenomonas ruminantium subsp. r uminantium GA192 (ATCC 12561; type strain) and S. ruminantium subsp. l actilytica HD4 (ATCC 27209) was done. These sequences were compared wi th those of other bacteria. Evolutionary distance estimates indicated that Quin's oval was most closely related to the Selenomonas-Megasphae ra-Sporomusa group in the gram-positive phylum but that it belongs in a new genus. We propose the name Quinella ovalis gen. nov., sp. nov., with its description based on previously known features.