Proposal of Quinella ovalis gen. nov., sp. nov., Based on Phylogenetic Analysis

Abstract

Quin's oval is a relatively large bacterium often seen in the rumens of 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 suspensions purified from rumen fluid by differential centrifugation. We obtained similarly purified suspensions from a sheep fed a diet containing a large amount of molasses. Nearly complete 16s rRNA sequence analysis of these cells as well as cells of Selenomonas ruminantiurn subsp. ruminantiurn GA192 (ATCC 12561; type strain) and S. ruminantium subsp. Zuctii'ytica HD, (ATCC 27209) was done. These sequences were compared with those of other bacteria. Evolutionary distance estimates indicated that Quin's oval was most closely related to the Selenomonas-Megasphaera-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.Quin's oval (QO) was briefly described by Woodcock and Lapage in 1913 (27) and separately discovered by Quin (16) in 1943. Quin found it in large numbers in the rumens of sheep fed diets of sugar-rich fresh alfalfa either alone or supplemented with molasses, sucrose, or glucose. Although he did not isolate it, he named it "Schizosaccharomyces ovis" because of its yeast-like (gassy) rapid fermentation of sugar, its relatively large (4-by-8 pm) oval to oblong-oval shape, and its reproduction by binary fission. He also found that it produces glycogen intracellular reserve material from part of the sugar used.Further studies on QO have been hampered by the inability of researchers to obtain pure cultures; however, a considerable number of its features have been determined by various techniques. For example, Howard and coworkers (2, 6, 23) obtained highly enriched cells by differential centrifugation of rumen fluid from sheep fed diets that promoted the growth of large numbers of 00. Using these suspensions, they obtained information on the carbohydrate fermented and the products produced and definitive information on glycogen storage. They also determined that since the cell walls of QO were shown to contain 2,4-diaminopimelic and muramic acids, it is a bacterium. Other studies, such as those of Orpin (13), which used very slow and meticulous culture techniques, have confirmed and extended the information on carbohydrate fermentation, motility, gram-negative staining, and several other features.QO is considered an important part of the microbiota of the rumens of sheep, and it occurs in numbers from 1.9 x lo5 to 3.0 x 108/ml (13). It has been found in numbers as high as 1Ol1/ml (21) in sheep fed mainly molasses. While no taxonomic information has been published on QO since the definitive studies showing that it is a bacterium (23), one of us (M.P.B.) has long surmised that it is at least * Corresponding author. somewhat related to Selenomonas ruminantium subspecies (4,15). Its fermentation produ...

Two Different Bacterial Community Types Are Linked with the Low-Methane Emission Trait in Sheep

“…This observation is consistent with the finding that LM1-associated ruminotype Q has a higher relative abundance of organisms closely related to Quinella ovalis (Quin’s oval; [19], [20]). Quin’s oval appears to ferment sugars to equimolar acetate and propionate [21], which is associated with lower H 2 formation than other fermentation pathways [22].…”

Programming rumen bacterial communities in newborn Merino lambs

“…The Quinella genus contains gram negative bacteria closely related to a gram-positive bacteria group (Krumholz et al, 1993) and is commonly found in the rumen of sheep eating lucerne with molasses which is consistent with the basal diet of the present study. The third most abundant group of different OTUs belonged to the genus Prevotella (gram-negative; Shah and Collins, 1990), with a role in the degradation of starch, plant cell wall polysaccharides and proteins (Stewart et al, 1997).…”

“…lambs nibbling pen materials and bedding) in comparison with the feed eaten by their dams. The percentage of molasses and lucerne in the total intake of lambs was less than in the diet of ewes, and it has been noted that members of Veillonellaceae are frequently detected in animals eating diets with molasses and lucerne (Krumholz et al, 1993). Furthermore, changes observed in bacterial taxonomy in lambs between ages support findings of Li et al (2012) and Jami et al (2013) who studying the rumen microbiota reported differences in the structure of the microbiota between cattle of different age.…”

Taxonomy and Systematics

“…Cluster VI embraces the members of Moorella, established for the former C. thermoaceticum [30]. This cluster also harbors Anaerovibrio lipolyticus [84], Mitsuokella multacida, Centipedia periodontii [85], Anaeromusa acidaminophila [86], Succinispira mobilis [87], Veillonella species, Dendrosporobacter quercicola [3], Quinella ovalis [88], Dialister pneumosintes [89], Anaerosinus glyzcerini [84], Anaeroarcus burkinensis [84], Acetonema longum [90], Succiniclasticum ruminis [91], and Schwartzia succinivorans [92]. Especially cluster IX contains a rich spectrum of different genera.…”