Ruminant livestock are important sources of human food and global greenhouse gas emissions. Feed degradation and methane formation by ruminants rely on metabolic interactions between rumen microbes and affect ruminant productivity. Rumen and camelid foregut microbial community composition was determined in 742 samples from 32 animal species and 35 countries, to estimate if this was influenced by diet, host species, or geography. Similar bacteria and archaea dominated in nearly all samples, while protozoal communities were more variable. The dominant bacteria are poorly characterised, but the methanogenic archaea are better known and highly conserved across the world. This universality and limited diversity could make it possible to mitigate methane emissions by developing strategies that target the few dominant methanogens. Differences in microbial community compositions were predominantly attributable to diet, with the host being less influential. There were few strong co-occurrence patterns between microbes, suggesting that major metabolic interactions are non-selective rather than specific.

ABSTRACTPyrosequencing of 16S rRNA genes (targetingBacteriaandArchaea) and1H nuclear magnetic resonance were applied to investigate the rumen microbiota and metabolites of Hanwoo steers in the growth stage (HGS), Hanwoo steers in the late fattening stage (HFS), Holstein-Friesian dairy cattle (HDC), and Korean native goats (KNG) in the late fattening stage. This was a two-part investigation. We began by comparing metabolites and microbiota of Hanwoo steers at two stages of husbandry. Statistical comparisons of metabolites and microbial communities showed no significant differences between HFS and HGS (differing by a dietary shift at 24 months and age [67 months versus 12 months]). We then augmented the study by extending the investigation to HDC and KNG. Overall, pyrosequencing of 16S rRNA genes showed that the rumens had highly diverse microbial communities containing many previously undescribed microorganisms. Bioinformatic analysis revealed that the bacterial sequences were predominantly affiliated with four phyla—Bacteroidetes,Firmicutes,Fibrobacteres, andProteobacteria—in all ruminants. However, interestingly, the bacterial reads belonging toFibrobactereswere present at a very low abundance (<0.1%) in KNG. Archaeal community analysis showed that almost all of these reads fell into a clade related to, but distinct from, known cultivated methanogens. Statistical analyses showed that the microbial communities and metabolites of KNG were clearly distinct from those of other ruminants. In addition, bacterial communities and metabolite profiles of HGS and HDC, fed similar diets, were distinctive. Our data indicate that bovine host breeds override diet as the key factor that determines bacterial community and metabolite profiles in the rumen.

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Enteric methane (CH 4 ) production attributable to beef cattle contributes to global greenhouse gas emissions. Reliably estimating this contribution requires extensive CH 4 emission data from beef cattle under different management conditions worldwide. The objectives were to: 1) predict CH 4 production (g d −1 animal −1 ), yield [g (kg dry matter intake; DMI)−1 ] and intensity [g (kg average daily gain) −1 ] using an intercontinental database (data from Europe, North America, Brazil, Australia and South Korea); 2) assess the impact of geographic region, and of higher-and lower-forage diets. Linear models were developed by incrementally adding covariates. A K-fold cross-validation indicated that a CH 4 production equation using only DMI that was fitted to all available data had a root mean square prediction error (RMSPE; % of observed mean) of 31.2%. Subsets containing data with

Two floc-forming, nitrogen-fixing bacteria, strains EMB43 T and EMB61, obtained from activated sludge of a domestic wastewater treatment plant in Korea, were characterized. The two strains were very closely related, sharing 99.7 % 16S rRNA gene sequence similarity and showing a level of DNA-DNA relatedness of 93 %, which suggests that they represent members of a single species. Phylogenetic analysis based on 16S rRNA gene sequences showed that the two novel isolates formed a distinct phyletic lineage within the genus Zoogloea and were related most closely to Zoogloea resiniphila DhA-35 T and Zoogloea oryzae A-7 T , with sequence similarities of 97.2 %. Levels of DNA-DNA relatedness between strain EMB43 T and Z. resiniphila DhA-35 T and Z. oryzae A-7 T were 12.8 and 7.4 %, respectively. Cells of strains EMB43 T and EMB61 were facultatively aerobic, rod-shaped, Gram-negative and motile by means of a polar flagellum. The strains grew at temperatures of 15-40 6C (optimum: 25-30 6C) and at pH 6.0-9.0 (optimum: pH 6.5-7.5). The predominant fatty acids were C 16 : 0 , C 10 : 0 3-OH and summed feature 3 (C 16 : 1 v7c and/or iso-C 15 : 0 2-OH), and the predominant polar lipid was phosphatidylethanolamine. The genomic DNA G+C content was 64.9-65.0 mol% and the major isoprenoid quinone was ubiquinone-8 (Q-8). On the basis of phenotypic, chemotaxonomic and molecular data, the isolates are considered to represent a novel species of the genus Zoogloea, for which the name Zoogloea caeni sp. nov. is proposed. The type strain is EMB43 T (5KCTC 22084 T 5DSM 19389 T ).Bacteria of the genus Zoogloea, a member of the family Rhodocyclaceae, are known to form characteristic cell aggregates embedded in gelatinous matrices, often called zoogloeal matrices (Dugan et al., 1992). Historically, the criteria used for taxonomic classification in this genus were based on phenotypic characteristics, which has resulted in confusion in identifying members of the genus and led to Zoogloea ramigera ATCC 25935 (5IAM 12670) being transferred to Duganella zoogloeoides based on molecular approaches (Hiraishi et al., 1997). At the time of writing, the genus Zoogloea comprises three recognized species, namely Z. ramigera (Crabtree & McCoy, 1967), Zoogloea resiniphila (Mohn et al., 1999) and Zoogloea oryzae (Xie & Yokota, 2006). Activated-sludge processes have been used to remove organic compounds as well as nutrients from wastewater, and insight into the bacterial communities is a prerequisite for understanding activated-sludge processes. Therefore, efforts have been made in our laboratory to isolate and characterize members of the bacterial community in activated sludge (Jeon et al., 2003;Lu et al., 2006;Park et al., 2007;Ryu et al., 2007). In the present study, we describe a novel species of the genus Zoogloea isolated from an activated-sludge process treating domestic sewage.Strains EMB43 T and EMB61 were isolated from activated sludge of a domestic wastewater treatment plant in Pohang,The GenBank/EMBL/DDBJ accession numbers for the 16S rRNA gene seq...

A Gram-negative-staining, non-spore-forming bacterium devoid of flagella, designated strain B9 T , was isolated from rice paddy soil associated with the roots of Oryza sativa collected from Jinju, South Korea. Cells were straight rods, were catalase-and oxidase-positive and were able to hydrolyse pectin, xylan and laminarin. Growth of strain B9 T was observed between 15 and 35 6C(optimum 25-30 6C) and between pH 5.0 and 8.0 (optimum pH 6.5-7.5). Strain B9 T contained menaquinone-7 (MK-7) as a major isoprenoid quinone and summed feature 3 (C 16 : 1 v7c and/or iso-C 15 : 0 2-OH), iso-C 15 : 0 and C 16 : 0 as major fatty acids. The G+C content of the genomic DNA was 44.4 mol%. Comparative 16S rRNA gene sequence analysis showed that strain B9 T belonged to the genus Mucilaginibacter, a member of the family Sphingobacteriaceae, and was most closely related to Mucilaginibacter kameinonensis SCK T (95.9 % sequence similarity). On

Until now, even though intensive research has been dedicated to the primo vascular system (PVS) during these years, no statistical data on primo vessels and primo vessels in lymph flow have been available. Recently, the general morphological features of primo vessels in lymph vessels around the abdominal aorta were identified from microdissections of tissues from New Zealand White rabbits, and with Alcian blue staining, primo vessels in lymphatic vessels could be definitely identified under a digital microscope. The micro-dissected specimens in situ reveal rod-shaped nuclei stained by Acridine orange. The blue-stained nuclei, which were distributed in a broken-lined stripe, formed a tube structure of about 20 μm in diameter. The distance between the nuclei of two cells on neighboring aligned stripes, which is also the diameter of the micro tube, was measured to be about 5∼10 μm. The average length of the primo vessels was 2.4 mm, with the longest being 5.6 mm. The average size of the primo vessel was 50 μm, and the average diameters of the primo and the lymph vessels were 26.0 μm and 258.5 μm, respectively. Occasionally, without the use of Alcian blue staining, milk-white transparent primo vessels were observed floating in lymph vessels. Thus, we suggest that the PVS might also have an important function connected with the lymph system. We also expect the traditional Korean meridian system to leave its invisible world during the last thousands of years and soon enter the visible scientific world.

A Gram-negative, non-spore-forming bacterium, designated strain BD-d46 T , was isolated from a playground soil sample in Jinju, South Korea. Cells were straight or curved rods and showed catalase-and oxidase-positive reactions. Growth of strain T was observed between 15and 35 6C (optimum 25-30 6C) and between pH 6.5 and 8.0 (optimum pH 7.0-7.5). The predominant fatty acids were summed feature 3 (C 16 : 1 v7c and/or iso-C 15 : 0 2-OH), C 12 : 0 3-OH and C 16 : 0 . Strain BD-d46 T contained phosphatidylethanolamine and phosphatidylglycerol as major polar lipids. Isoprenoid quinones were Q-8 (75 %) and MK-7 (25 %). The G+C content of the genomic DNA was 49.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain BD-d46 T formed a distinct lineage with Rheinheimera chironomi K19414 T within the genus Rheinheimera. Levels of 16S rRNA gene sequence similarity between strain BDd46 T and the type strains of recognized Rheinheimera species ranged from 94.4 to 96.9 %. On the basis of chemotaxonomic data and molecular properties, strain BD-d46