Chemische Untersuchungen über unterschiedlich vorbehandelte Federmehle

Abstract

Dr. Carlheinrich Engelmann: Ernährung und Fütterung des Geflügels. Erschienen im Neumann-Verlag Radebeul/Berlin, 162 Seiten, 17 × 24 cm Halbleinen, MDN 6,80. Reviewed by H. Bergner

Dr. Martin Pankrath: Wasserbedarf landwirtschaftlicher Nutztiere — Mengennormen. - Erschienen im S. Hirzel Verlag, Leipzig C 1, Schuhmachergäßchen 1–3. 1. Auflage 1963, 99 Seiten mit 25 Diagrammen, 21 Tabellen und 2 Tafeln im Text. 8°, Hln., MDN 10,70. Reviewed by H. Bergner

Physiologische und wirtschaftliche Leistungsgrenzen in der Tierzucht 14 Vorträge eines internationalen Symposions im Max-Planck-Institut für Tierzucht und Tierernährung in Mariensee vom 14. bis 17. Oktober 1963.: Herausgegeben von M. Witt. 315 Seiten mit 8 Kunstdrucktafeln. Englische Summaries. Steif broschiert, Preis DM 16,-. Bestellung über Institut. Reviewed by H. Bergner     

Estimation of net nutrient oxidation and lipogenesis in growing pigs

Data from previous series of trials were reevaluated in order to quantify the net nutrient oxidation and lipogenesis by combining data from balance experiments and indirect calorimetry measurements. The experiments were carried out with eight castrated males of Danish Landrace measured individually from 30 to 100 kg BW. All pigs were fed alternately on high feeding level, near ad libitum and on low feeding level, near maintenance. Oxidation of carbohydrate (OXCHO) and fat (OXF) was calculated from gas exchange measurements. On high feeding level the contribution from OXCHO and OXF to the total heat production was 55 and 30%, respectively, at 30 kg BW and fairly constant from 60 kg BW with OXCHO around 80% and no net OXF. At low feeding level the contribution from OXCHO and OXF was 28 and 63%, respectively, at 30kg BW, increasing to 52% for OXCHO and decreasing to 37% for OXF at 95 kg BW. The lipogenesis on high feeding level increased from 2.4 to 11.9 MJ/d, while on low feeding level it increased from 2.5 to 3.6 MJ/d at 30 to 95 kg BW. The intake of carbohydrate was too low to cover energy requirement by OXCHO on low feeding level and in the first periods on high feeding level and OXF occurred. In spite of a deficit of carbohydrate for oxidation a part of carbohydrate (2.6 MJ/d, ～ 150 g/d) was used for fat synthesis, indicating an importance of lipogenesis in growing pigs.     

Acetate oxidation by syntrophic association between Geobacter sulfurreducens and a hydrogen-utilizing exoelectrogen

Anodic microbial communities in acetate-fed microbial fuel cells (MFCs) were analyzed using stable-isotope probing of 16S rRNA genes followed by denaturing gradient gel electrophoresis. The results revealed that Geobacter sulfurreducens and Hydrogenophaga sp. predominated in the anodic biofilm. Although the predominance of Geobacter sp. as acetoclastic exoelectrogens in acetate-fed MFC systems has been often reported, the ecophysiological role of Hydrogenophaga sp. is unknown. Therefore, we isolated and characterized a bacterium closely related to Hydrogenophaga sp. (designated strain AR20). The newly isolated strain AR20 could use molecular hydrogen (H₂), but not acetate, with carbon electrode as the electron acceptor, indicating that the strain AR20 was a hydrogenotrophic exoelectrogen. This evidence raises a hypothesis that acetate was oxidized by G. sulfurreducens in syntrophic cooperation with the strain AR20 as a hydrogen-consuming partner in the acetate-fed MFC. To prove this hypothesis, G. sulfurreducens strain PCA was cocultivated with the strain AR20 in the acetate-fed MFC without any dissolved electron acceptors. In the coculture MFC of G. sulfurreducens and strain AR20, current generation and acetate degradation were the highest, and the growth of strain AR20 was observed. No current generation, acetate degradation and cell growth occurred in the strain AR20 pure culture MFC. These results show for the first time that G. sulfurreducens can oxidize acetate in syntrophic cooperation with the isolated Hydrogenophaga sp. strain AR20, with electrode as the electron acceptor.     

Chemically defined media modifications to lower tryptophan oxidation of biopharmaceuticals

Oxidation of biopharmaceuticals is a major product quality issue with potential impacts on activity and immunogenicity. At Eli Lilly and Company, high tryptophan oxidation was observed for two biopharmaceuticals in development produced in Chinese hamster ovary cells. A switch from historical hydrolysate‐containing media to chemically defined media with a reformulated basal powder was thought to be responsible, so mitigation efforts focused on media modification. Shake flask studies identified that increasing tryptophan, copper, and manganese and decreasing cysteine concentrations were individual approaches to lower tryptophan oxidation. When amino acid and metal changes were combined, the modified formulation had a synergistic impact that led to substantially less tryptophan oxidation for both biopharmaceuticals. Similar results were achieved in shake flasks and benchtop bioreactors, demonstrating the potential to implement these modifications at manufacturing scale. The modified formulation did not negatively impact cell growth and viability, product titer, purity, charge variants, or glycan profile. A potential mechanism of action is presented for each amino acid or metal factor based on its role in oxidation chemistry. This work served not only to mitigate the tryptophan oxidation issue in two Lilly biopharmaceuticals in development, but also to increase our knowledge and appreciation for the impact of media components on product quality. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 32:178–188, 2016     

厌氧氨氧化体的组成、结构与功能

厌氧氨氧化(Anammox)是微生物和环境领域的研究热点之一。厌氧氨氧化菌(AnAOB)是Anammox的功能载体。不同于大部分原核微生物,AnAOB具有独特的细胞器——厌氧氨氧化体,它是进行Anammox代谢的场所。研究厌氧氨氧化体有助于探明厌氧氨氧化菌的代谢特性。本文综述了厌氧氨氧化体的组成、结构与功能,以期为从事Anammox研究的同行提供参考。     

Chemiluminescence analysis of antioxidant capacity for serum albumin isolated from healthy or uremic volunteers

Regular hemodialysis treatment induces an elevation in oxidative stress in patients with end‐stage renal failure, resulting in oxidative damage of the most abundant serum protein, albumin. Oxidation of serum albumin causes depletion of albumin reactive thiols, leading to oxidative modification of serum albumin. The aim of this study was to screen the antioxidant capacity of albumins isolated from uremic patients (HD‐ALB) or healthy volunteers (N‐ALB). From high‐performance liquid chromatography spectra, we observed that one uremic solute binds to HD‐ALB via the formation of disulfide bonds between HD‐ALB and the uremic solute. Furthermore, we found using chemiluminescent analysis that the antioxidant capacities for N‐ALB to scavenge reactive oxygen species including singlet oxygen, hypochlorite and hydrogen peroxide were higher than HD‐ALB. Our results suggest that protein‐bound uremic solute binds to albumin via formation of disulfide bonds, resulting in the depletion of albumin reactive thiols. The depletion of albumin reactive thiols leads to a reduced antioxidant capacity of HD‐ALB, implying postmodification of albumin. This situation may reduce the antioxidant capacity of albumin and increase oxidative stress, resulting in increase in complications related to oxidative damage in uremic patients. Copyright © 2016 John Wiley & Sons, Ltd.     

嗜热革节孢多糖单加氧酶氧化方式

多糖单加氧酶(polysaccharidemonooxygenase,PMO)是一种铜离子依赖的氧化酶,属于辅助活性酶类第九家族(auxiliary activity 9,AA9),在存在电子供体维生素C(vitamin C,Vc)的情况下,可以氧化裂解纤维素的多糖链,显著提高纤维素的酶解效率。本文克隆了嗜热革节孢Scytalidium thermophilumAA9家族的一个编码基因pmo7651,并在毕赤酵母GS115进行诱导表达,通过His标签获得了重组蛋白PMO7651-His。以磷酸膨胀纤维素(PASC)为底物进行酶促反应,薄层层析法(TLC)结果显示PMO7651酶解产物主要为纤维二糖至纤维五糖;飞行时间质谱法(MALDI-TOF-MS)和溴氧化法确定PMO7651具有C1、C4、C6位的氧化活性;底物结合平面的3个芳香族氨基酸位点突变对酶的活性具有不同程度的影响;在PMO7651帮助下,纤维素酶的降解效率均具有不同程度的提高。