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.

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A genome-wide scan for QTL affecting economically important traits in beef production was performed using an F(2) resource family from a Japanese Black x Limousin cross, where 186 F(2) animals were measured for growth, carcass, and meat-quality traits. All family members were genotyped for 313 informative microsatellite markers that spanned 2,382 cM of bovine autosomes. The centromeric region of BTA2 contained significant QTL (i.e., exceeding the genome-wide 5% threshold) for 5 carcass grading traits [LM area, beef marbling standards (BMS) number, luster, quality grade, and firmness), 8 computer image analysis (CIA) traits [LM lean area, ratio of fat area (RFA) to LM area, LM area, RFA to musculus (M.) trapezius area, M. trapezius lean area, M. semispinalis lean area, RFA to M. semispinalis area, and RFA to M. semispinalis capitis area], and 5 meat quality traits (contents of CP, crude fat, moisture, C16:1, and C18:2 of LM). A significant QTL for withers height was detected at 80.3 cM on BTA5. We detected significant QTL for the C14:0 content in backfat and C14:0 and C14:1 content in intermuscular fat around the 62.3 to 71.0 cM region on BTA19 and for C14:0, C14:1, C18:1, and C16:0 content and ratio of total unsaturated fatty acid content to total SFA content in intramuscular fat at 2 different regions on BTA19 (41.1 cM for C14:1 and 62.3 cM for the other 4 traits). Overall, we identified 9 significant QTL regions controlling 27 traits with genome-wide significance of 5%; of these, 22 traits exceeded the 1% genome-wide threshold. Some of the QTL affecting meat quality traits detected in this study might be the same QTL as previously reported. The QTL we identified need to be validated in commercial Japanese Black cattle populations.

Phospholipase B has not yet been well defined. The most important points about this enzyme are its relationships with lysophospholipase and phospholipase Al. As reported [Saito, K., Sugatani, J. & Okumura, T. (1991) Mc>thod,s Enzymol. 197, 446 -4561, Penicillium notutum phospholipase B is a glycoprotein with a molecular mass of 95 kDa and intrinsic lysophospholipase and phospholipase B activities; however, by endogenous proteolytic modification, its phospholipase B activity is lost almost completely, whereas its lysophospholipase activity remains unchanged.A cDNA library of P. notaturn was screened by hybridization with two synthetic oligodeoxyribonucleotide probes, which corresponds to two different pentapeptides of the enzyme. A hybridization-positive clone, pPLBl8, was isolated and its nucleotide sequence was determined. The deduced amino acid sequence was quite different from that found previously. Therefore, we rescreened the cDNA hbrdry with a Suu3AI fragment derived from pPLB18 and isolated a new clone, pPLB15. Comparison of the nucleotide sequences of pPLB15 and pPLB18 revealed that pPLB18 contained an insertion sequence of 53 bp. Consequently, the reading frame was open downstream for 603 amino acid residues.From the assigned sequence, it was deduced that the limited proteolysis occurred between Leu175 and Asp176; eight cysteine residues and 16 potential N-glycosylation sites were also found. No amino acid sequence similarity was found with other proteins, including other phospholipases.Phospholipase B has been found in microorganisms, plants and animal tissues; in many cases it has lysophospholipase activity in addition to phospholipase B activity, as reviewed by van Penicilliurn notutum phospholipase B is a glycoprotein with a molecular mass of about 95 kDa and intrinsic phospholipase B and lysophospholipase activities. However, on proteolytic modification with an endogenous protease(s), phospholipase B activity was almost completely lost, whereas lysophospholipase activity was unaffected [5].In this paper, we describe the isolation of a cDNA for the phospholipase B from P. notaturn and assign the primary structure of the protein moiety of this enzyme. The primary structure is discussed in relation to the enzymatic properties reported before [5, 61, and also to lysophospholipase and phospholipase A l .

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