Structure of fungal fatty acid synthase and implications for iterative substrate shuttling     

Jenni S  Leibundgut M  Boehringer D  Frick C  Mikolásek B  Ban N 《Science (New York, N.Y.)》2007,316(5822):254-261

We report crystal structures of the 2.6-megadalton alpha6beta6 heterododecameric fatty acid synthase from Thermomyces lanuginosus at 3.1 angstrom resolution. The alpha and beta polypeptide chains form the six catalytic domains required for fatty acid synthesis and numerous expansion segments responsible for extensive intersubunit connections. Detailed views of all active sites provide insights into substrate specificities and catalytic mechanisms and reveal their unique characteristics, which are due to the integration into the multienzyme. The mode of acyl carrier protein attachment in the reaction chamber, together with the spatial distribution of active sites, suggests that iterative substrate shuttling is achieved by a relatively restricted circular motion of the carrier domain in the multifunctional enzyme.  相似文献   

Genetic diversity analysis of Afghan wheat landraces (Triticum aestivum) using DArT markers     

Quahir Sohail  Alagu Manickavelu  Tomohiro Ban 《Genetic Resources and Crop Evolution》2015,62(8):1147-1157

  相似文献   

2018年河南省未免疫羊群布鲁氏菌病流行情况调查     

赵胜杰  陶龙斐  周琳  刘光辉  房大学  郭洛生  班付国 《中国动物检疫》2019,36(9):5-8

为了解河南省未免疫羊群布鲁氏菌感染情况，2018年以河南省未免疫布鲁氏菌病疫苗的羊群为研究对象，开展羊群布鲁氏菌病血清学普查，共对1 830个场群的59 462份血清样品进行布鲁氏菌抗体检测，并对结果进行空间、群间分布分析。结果显示：河南省羊群布鲁氏菌感染抗体平均场群阳性率为3.93%，个体阳性率为1.24%；豫西地区场群流行率和个体流行率均最高，分别为12.31%和6.43%，豫东地区最低，分别为0.55%和0.04%；散养户的场群阳性率和个体阳性率均最高，分别为7.53%和2.17%，而羊屠宰场和交易市场中未检出阳性。结果表明：豫西地区以及散养户羊群布鲁氏菌病流行情况较为严重，应采取全面免疫的防控措施，降低该地的布鲁氏菌病流行率；豫东、豫南地区和种羊场等流行率较低的地区和场点，可采取检测、扑杀等措施，逐步实现净化目标；羊屠宰场和交易市场虽然无阳性检出，但应继续加强监测，防止病菌交叉传播。通过本次河南省未免疫羊群普查，基本掌握了全省未免疫羊群的布鲁氏菌病流行状况，从而为全省羊群布鲁氏菌病防控提供了重要的参考数据。  相似文献   

塔拉精粉的安全性评价     

包松莲  李志国  张建云 《东北林业大学学报》2008,36(4):61-62

检验了塔拉豆荚提取的活性物质——塔拉精粉的毒理、感官和理化指标。结果表明:塔拉精粉对受试动物小白鼠急性经口毒性试验LD50大于实验所用m(塔拉精粉)∶m(小鼠)=1∶100的比值,属实际无毒级,达到实际无毒级标准;对小白鼠骨髓细胞无致微核作用,对小白鼠精子细胞无致畸作用。感官和理化指标检测结果全部在国家相关产品所允许的指标范围之内。  相似文献   

The influence of a spring habit gene, Vrn-D1, on heading time in wheat     

H. Kato    S. Taketa    T. Ban    N. Iriki  K. Murai 《Plant Breeding》2001,120(2):115-120

The adaptability of wheat cultivars to environmental conditions is known to be associated with a vernalization requirement, that is, spring/winter habit. To clarify the genetic effect of the spring habit gene, Vrn‐D1, on heading time in the field, recombinant inbred lines (RILs) with or without the Vrn‐D1 gene were produced from F₂ plants of the cross between ‘Nanbukomugi’ and ‘Nishikazekomugi’, non‐carrier and carrier cultivars of this gene, respectively. Using growth chambers with a controlled temperature and photoperiod, three components of heading time, i.e. vernalization requirement, photoperiodic sensitivity and narrow‐sense earliness (earliness per se), were evaluated in each RIL. RILs with the Vrn‐D1 gene (E lines) showed greatly reduced vernalization requirements and slightly shorter narrow‐sense earliness than RILs without Vrn‐D1 (L lines), although no difference in photoperiodic sensitivity was observed between the two groups. RILs were planted at four different sites in Japan and examined for their heading time in the field. E lines headed significantly earlier than L lines at all locations, indicating that the earliness of E lines is stable in various environmental conditions. These results indicated that spring habit caused by Vrn‐D1 gene, as well as narrow‐sense earliness, was responsible for heading time in the field.  相似文献   

对我国主要类型区生态农业模式的分析     

毕绪岱  班勇 《中国生态农业学报》1995,3(2):4-9

本文主要针对我国华北、西北和中南地区，概要分析主要生态农业模式的区位分布特点，进而探讨各区位适宜重点发展的生态农业类型及需要优先解决的区位关系。提出缩减上游山区边际耕地面积，扩大造林（含经济树种、植物），发展种草养畜，实行资源环境建设补偿机制，推动区域生态农业建设，从而使我国农业向着高产、优质、高效持续方向健康发展。  相似文献   

Net energy,energy utilization,and nitrogen and energy balance affected by dietary pea supplementation in broilers     

Nishchal K. Sharma  Zhibin Ban  Hank L. Classen  Huaming Yang  Xiaogang Yan  Mingan Choct  Shu-Biao Wu 《动物营养（英文）》2021,7(2):506

Pea starch consists predominantly of C-type of amylopectin chain which is more resistant to digestive enzymes than A-type of starch thus slowly digested in poultry. It was hypothesized that the presence of slowly digested pea starch in broiler diets will increase net energy and the efficiency of energy utilization in broilers. Two experiments were performed to investigate starch digestibility of pea at different incubation times (in vitro study) and the effect of dietary pea on heat increment and net energy in broilers using an open-circuit respiratory calorimetry system (in vivo study). One-day-old Ross 308 male broilers were fed a common starter crumble from d 1 to 10 and standard grower diets thereafter. At d 21, birds were transferred to the chambers each housing 2 birds. Each treatment was replicated 6 times with 2 identical runs of 3 replicates per treatment. A wheat-soybean meal-based diet was used as a control and the treatment diet contained 500 g of pea/kg pea. In vitro study showed that pellet processing increased (P < 0.001) starch digestibility, particularly at shorter times for wheat and a much larger response for pea. Birds offered the pea-based diet had lower (P = 0.002) feed intake, lower (P = 0.020) body weight gain, but a similar (P > 0.05) FCR compared to those offered the wheat-based diet. Net energy (NE) and apparent metabolizable energy (AME) values were higher in the pea-based diet than in the wheat-based diet (P = 0.037 for NE and P = 0.018 for AME). Heat production, respiratory quotient, heat increment of feed, efficiency of utilization of gross energy for AME, and efficiency of utilization of AME for NE did not differ (P > 0.05) between the 2 treatments. There was no effect (P > 0.05) of pea on the total tract digestibilities of dry matter, crude protein and ash, but the total tract digestibility of starch was higher (P = 0.022) in the pea-based diet compared to the wheat-based diet. This study provides insight into the energy metabolism of broilers offered a pea-based diet and indicates that dietary pea supplementation increases dietary AME and NE but has no effect on heat increment of feed and the efficiency of energy utilization in broilers.  相似文献   

达氟沙星对试验性感染仔猪副伤寒和霉形体肺炎的药效学研究   总被引：3，自引：0，他引：3  

胡功政  刘冰宏等 《华中农业大学学报》2001,20(2):151-155

研究了国产新兽药达氟沙星对人工感染仔猪伤寒和霉形体肺炎的疗效。每个疗效试验用仔猪105只，随机分为达氟沙星3个不同剂量组，恩诺沙星对照组，强力霉素对照组，阳性对照组和阴性对照组，每组动物15只。当感染猪出现典型症状时，达氟沙星3个剂量组分别按每千克体重2．5ml,1.25mg,0.625mg，0.625mg及恩诺沙星组按2．5mg肌肉注射，每日2次，强力霉素按每千克体重3mg肌肉注射，每日2次。结果表明：达氟沙星3个不同剂量组、恩诺沙星组、强力霉素组连续用药4d，对仔猪副伤寒的治愈率分别是100％、80％、33．3％、80％、53．3％、而感染（阳性）对照组的死亡率为66．7％；达氟沙星3个不同剂量组、恩诺沙星组、强力霉素组连续用药5d,对霉形体肺炎的治愈率分别是100％、80％、93．3％，肺部病变率分别是20％、40％、60％、20％、60％，而感染（阳性）对照组的死亡率为40％，肺部病变率为1005。  相似文献   

Polymorphisms in mannose-binding lectin (MBL) gene and their association with MBL protein levels in serum in the Hu sheep   总被引：1，自引：0，他引：1  

Zhao F  Zhao Z  Yan G  Wang D  Ban Q  Yu P  Zhang W  Luo Y 《Veterinary immunology and immunopathology》2011,140(3-4):297-302

Mannose-binding lectin (MBL) is the archetypical pathogen recognition protein of the innate immune defence. In humans, three frequently occurring single nucleotide polymorphisms (SNPs) in the coding region of MBL gene are associated with the abnormal polymerization, decreased serum concentration and strongly impaired function of MBL protein. To understand whether or not SNPs in MBL gene are associated with serum concentration of MBL in sheep, we investigated 105 individuals of the Hu sheep by PCR single-strand conformation polymorphism (SSCP) analysis, DNA sequencing, and enzyme-linked immunosorbent assay. SSCP analyses of PCR amplicons from a 194-bp section of the exon-I region of the MBL gene revealed four patterns: A, B, C and D. In comparison with the sequences of the full-length MBL gene of sheep (GenBank accession numbers FJ977629 and AM933378; reference sequence hereafter), pattern A has a 3-bp deletion, a 6-bp deletion and 42 SNPs. Pattern B has 3 SNPs, pattern C has 2 SNPs, whereas pattern D is identical to the reference sequence. Twenty-four of the 47 SNPs of the four patters are synonymous whereas the other 23 SNPs are non-synonymous. The two deletions in the pattern A result in deletions of amino acids but there are no frame shifts in the putative MBL protein. The concentration of MBL protein in serum ranges from 1571 to 3657 μg/L in the Hu sheep. Our statistic analyses showed that patterns A and B are associated with reduced MBL protein level in serum, whereas pattern C is associated with increased MBL protein level in serum (P<0.05) in the Hu sheep.  相似文献   

Effect of jasmonates on ethylene biosynthesis and aroma volatile emission in Japanese apricot infected by a pathogen (Colletotrichum gloeosporioides)     

Nimitkeatkai H  Shishido M  Okawa K  Ohara H  Ban Y  Kita M  Moriguchi T  Ikeura H  Hayata Y  Kondo S 《Journal of agricultural and food chemistry》2011,59(12):6423-6429

The effects of the application of the jasmonic acid derivative n-propyl dihydrojasmonate (PDJ) on ethylene biosynthesis, volatile compounds, and endogenous jasmonic acid (JA) and methyl jasmonate (MeJA) were examined in Japanese apricot (Prunus mume Sieb.) infected by a pathogen (Colletotrichum gloeosporioides). The fruit were dipped into 0.4 mM PDJ solution before inoculation with the pathogen and stored at 25 °C for 6 days. The inoculation induced an increase in 1-aminocyclopropane-1-carboxylic acid (ACC), ethylene, JA, and MeJA. In contrast, PDJ application reduced the endogenous JA, MeJA, and ethylene production and expression of the ACC oxidase gene (PmACO1) caused by the pathogen infection. The lesion diameter with C. gloeosporioides decreased upon PDJ application. The alcohol, ester, ketone, and lactone concentrations and alcohol acyltransferase (AAT) activity increased in the pathogen-infected fruit, but were decreased by PDJ application. These results suggest that PDJ application might influence ethylene production through PmACO1 and that aroma volatile emissions affected by pathogen infection can be correlated with the ethylene production, which is mediated by the levels of jasmonates.  相似文献