CONTRACT FINISHING FOR NEW ENTRANTS IN PORK PRODUCTION

The pork production industry is a far different industry today than it was fifty, twenty, or even five years ago. On diversified Midwestern farms during the mid-to-late 20th century, the swine enterprise was labeled "the mortgage lifter". The hogs added value to home-produced feedstuffs such as corn and increased the income from a given acreage base. As farm mechanization and technology rapidly developed, farms became larger and less diversified as livestock disappeared from many farmsteads. In this paper, we address the question whether swine units can be introduced to non-livestock farms via a coordinated agreement for the grower-finisher phase and make these farms more profitable. To do this, we first describe some of the changes that have taken place in the pork industry. Second, production contracts and grower payments are introduced. Next, we move on to issues of manure management and the value of manure to non-livestock farms. Finally, in the Appendix, financial analyses for sample contract finishing contracts are laid out to help farmers determine if contract finishing could benefit their farming operations.Livestock Production/Industries,

Effects of Removal and Remixing of Heavyweight Pigs on Performance to Slaughter Weights

An experiment was conducted to determine the effects of heavyweight pig removal and remixing on performance. The experiment used a total of 450 pigs (31 kg initial BW) that were sorted and remixed at a mean replicate BW of 73 kg. Treatments were 15 pigs/pen from initial BW to slaughter (15S), 20 pigs/pen from initial BW to time of sort and remix, then reduced to 15 pigs/pen (20/ 15), and 15 pigs/pen from time of sort and remix to slaughter, comprised of the 5 heaviest pigs from each of three 20/15 pens per replicate (15M). Space allocation was 0.56 m2/pig to the day of remixing and 0.74 m2/pig thereafter. There was no effect (P \u3e 0.1) of treatment on ADG before 73 kg BW when pens were 1A contribution of the University of Nebraska Agricultural Research Division, Lincoln, NE 68583. Journal series no. 14679. 2To whom correspondence should be addressed: [email protected] 3Committee members during the study in addition to those listed above were G. Apgar, SIU; M. Carlson, MO; R. K. Christenson, USDA-ARS RLH USMARC; L. Christianson, IL; M. Ellis, IL; R. Goodband, KSU; J. D. Harmon, IA; M. Honeyman, IA; D. D. Jones, IN; S. J. Moeller, OH; B. Richert, IN; K. Stalder, TN; R. C. Thaler, SD. the experimental units. There was no effect (P \u3e 0.1) of treatment on ADG or feed conversion to slaughter BW following removal and remixing using the contrast 20/15 + 15M vs. 15S. The average of the replicate for 20/15 and 15M was used as the experimental unit in a second statistical analysis. Daily feed was less (P = 0.079) from placement to 73 kg BW for the 20/15 + 15M population vs. the 15S population resulting in a lesser (P = 0.067) overall ADG (0.875 vs. 0.887 kg/d, respectively) with no effect (P \u3e 0.1) on feed conversion or CV sample population BW. Removal and remixing of heavyweight pigs at a midpoint in the growth process had minimal effects on performance to slaughter and CV for BW at slaughter

The fully conserved Asp residue in conserved sequence region I of the alpha-amylase family is crucial for the catalytic site architecture and activity

AbstractThe α-amylase family is a large group of starch processing enzymes [Svensson, B. (1994) Plant Mol. Biol. 25, 141–157]. It is characterized by four short sequence motifs that contain the seven fully conserved amino acid residues in this family: two catalytic carboxylic acid residues and four substrate binding residues. The seventh conserved residue (Asp135) has no direct interactions with either substrates or products, but it is hydrogen-bonded to Arg227, which does bind the substrate in the catalytic site. Using cyclodextrin glycosyltransferase as an example, this paper provides for the first time definite biochemical and structural evidence that Asp135 is required for the proper conformation of several catalytic site residues and therefore for activity

Site-Directed Mutations in Tyrosine 195 of Cyclodextrin Glycosyltransferase from Bacillus circulans Strain 251 Affect Activity and Product Specificity

Tyrosine 195 is located in the center of the active site cleft of cyclodextrin glycosyltransferase (EC 2.4.1.19) from Bacillus circulans strain 251. Alignment of amino acid sequences of CGTases and alpha-amylases, and the analysis of the binding mode of the substrate analogue acarbose in the active site cleft [Strokopytov, B., et al. (1995) Biochemistry 34, (in press)], suggested that Tyr195 plays an important role in cyclization of oligosaccharides. Tyr195 therefore was replaced with Phe (Y195F), Trp (Y195W), Leu (Y195L), and Gly (Y195G). Mutant proteins were purified and crystallized, and their X-ray structures were determined at 2.5-2.6 Angstrom resolution, allowing a detailed comparison of their biochemical properties and three-dimensional structures with those of the wild-type CGTase protein. The mutant proteins possessed significantly reduced cyclodextrin forming and coupling activities but were not negatively affected in the disproportionation and saccharifying reactions. Also under production process conditions, after a 45 h incubation with a 10% starch solution, the Y195W, Y195L, and Y195G mutants showed a lower overall conversion of starch into cyclodextrins. These mutants produced a considerable amount of linear maltooligosaccharides. The presence of aromatic amino acids (Tyr or Phe) at the Tyr195 position thus appears to be of crucial importance for an efficient cyclization reaction, virtually preventing the formation of linear products. Mass spectrometry of the Y195L reaction mixture, but not that of the other mutants and the wild type, revealed a shift toward the synthesis (in low yields) of larger products, especially of beta- and gamma- (but no alpha-) cyclodextrins and minor amounts of delta-, epsilon-, zeta- and eta-cyclodextrins. This again points to an important role for the residue at position 195 in the formation of cyclic products

The remote substrate binding subsite-6 in cyclodextrin-glycosyltransferase controls the transferase activity of the enzyme via an induced-fit mechanism

Cyclodextrin-glycosyltransferase (CGTase) catalyzes the formation of alpha-, beta-, and gamma-cyclodextrins (cyclic alpha-(1,4)-linked oligosaccharides of 6, 7, or 8 glucose residues, respectively) from starch. Nine substrate binding subsites were observed in an x-ray structure of the CGTase from Bacillus circulans strain 251 complexed with a maltononaose substrate. Subsite -6 is conserved in CGTases, suggesting its importance for the reactions catalyzed by the enzyme. To investigate this in detail, we made six mutant CGTases (Y167F, G179L, G180L, N193G, N193L, and G179L/G180L). All subsite -6 mutants had decreased k(cat) values for beta-cyclodextrin formation, as well as for the disproportionation and coupling reactions, but not for hydrolysis. Especially G179L, G180L, and G179L/G180L affected the transglycosylation activities, most prominently for the coupling reactions. The results demonstrate that (i) subsite -6 is important for all three CGTase-catalyzed transglycosylation reactions, (ii) Gly-180 is conserved because of its importance for the circularization of the linear substrates, (iii) it is possible to independently change cyclization and coupling activities, and (iv) substrate interactions at subsite -6 activate the enzyme in catalysis via an induced-fit mechanism. This article provides for the first time definite biochemical evidence for such an induced-fit mechanism in the alpha-amylase family

Survey of Revegetated Areas on the Fitzner/Eberhardt Arid Lands Ecology Reserve: Status and Initial Monitoring Results

During 2010, the U.S. Department of Energy (DOE), Richland Operations Office removed a number of facilities and debris from the Fitzner/Eberhardt Arid Lands Ecology Reserve (ALE), which is part of the Hanford Reach National Monument (HRNM). Revegetation of disturbed sites is necessary to stabilize the soil, reduce invasion of these areas by exotic weeds, and to accelerate re-establishment of native plant communities. Seven revegetation units were identified on ALE based on soils and potential native plant communities at the site. Native seed mixes and plant material were identified for each area based on the desired plant community. Revegetation of locations affected by decommissioning of buildings and debris removal was undertaken during the winter and early spring of 2010 and 2011, respectively. This report describes both the details of planting and seeding for each of the units, describes the sampling design for monitoring, and summarizes the data collected during the first year of monitoring. In general, the revegetation efforts were successful in establishing native bunchgrasses and shrubs on most of the sites within the 7 revegetation units. Invasion of the revegetation areas by exotic annual species was minimal for most sites, but was above initial criteria in 3 areas: the Hodges Well subunit of Unit 2, and Units 6 and 7

Mutational and structural analysis of an ancestral fungal dye decolorizing peroxidase

Dye-decolorizing peroxidases (DyPs) constitute a superfamily of heme-containing peroxidases that are related neither to animal nor to plant peroxidase families. These are divided into four classes (types A, B, C, and D) based on sequence features. The active site of DyPs contains two highly conserved distal ligands, an aspartate and an arginine, the roles of which are still controversial. These ligands have mainly been studied in class A-C bacterial DyPs, largely because no effective recombinant expression systems have been developed for the fungal (D-type) DyPs. In this work, we employ ancestral sequence reconstruction (ASR) to resurrect a D-type DyP ancestor, AncDyPD-b1. Expression of AncDyPD-b1 in Escherichia coli results in large amounts of a heme-containing soluble protein and allows for the first mutagenesis study on the two distal ligands of a fungal DyP. UV-Vis and resonance Raman (RR) spectroscopic analyses, in combination with steady-state kinetics and the crystal structure, reveal fine pH-dependent details about the heme active site structure and show that both the aspartate (D222) and the arginine (R390) are crucial for hydrogen peroxide reduction. Moreover, the data indicate that these two residues play important but mechanistically different roles on the intraprotein long-range electron transfer process. Database: Structural data are available in the PDB database under the accession number 7ANV.</p

Kinetic and structural properties of a robust bacterial l‐ amino acid oxidase

L-Amino acid oxidase (LAAO) is a flavin adenine dinucleotide (FAD)-dependent enzyme active on most proteinogenic L-amino acids, catalysing their conversion to α-keto acids by oxidative deamination of the substrate. For this oxidation reaction, molecular oxygen is used as the electron acceptor, generating hydrogen peroxide. LAAO can be used to detect L-amino acids, for the production of hydrogen peroxide as an oxidative agent or antimicrobial agent, and for the production of enantiopure amino acids from racemates. In this work, we characterised a previously reported LAAO from the bacterium Pseudoalteromonas luteoviolacea. The substrate scope and kinetic properties of the enzyme were determined, and the thermostability was evaluated. Additionally, we elucidated the crystal structure of this bacterial LAAO, enabling us to test the role of active site residues concerning their function in catalysis. The obtained insights and ease of expression of this thermostable LAAO provides a solid basis for the development of engineered LAAO variants tuned for biosensing and/or biocatalysis