Expression of Anti-Lipopolysaccharide Factor Isoform 3 in Chlamydomonas reinhardtii Showing High Antimicrobial Activity

Antimicrobial peptides are a class of proteins with antibacterial functions. In this study, the anti-lipopolysaccharide factor isoform 3 gene (ALFPm3), encoding an antimicrobial peptide from Penaeus monodon with a super activity was expressed in Chlamydomonas reinhardtii, which would develop a microalga strain that can be used for the antimicrobial peptide production. To construct the expression cluster, namely pH2A-Pm3, the codon optimized ALFPm3 gene was fused with the ble reporter by 2A peptide and inserted into pH124 vector. The glass-bead method was performed to transform pH2A-Pm3 into C. reinhardtii CC-849. In addition to 8 μg/mL zeocin resistance selection, the C. reinhardtii transformants were further confirmed by genomic PCR and RT-PCR. Western blot analysis showed that the C. reinhardtii-derived ALFPm3 (cALFPm3) was successfully expressed in C. reinhardtii transformants and accounted for 0.35% of the total soluble protein (TSP). Furthermore, the results of antibacterial assay revealed that the cALFPm3 could significantly inhibit the growth of a variety of bacteria, including both Gram-negative bacteria and Gram-positive bacteria at a concentration of 0.77 μM. Especially, the inhibition could last longer than 24 h, which performed better than ampicillin. Hence, this study successfully developed a transgenic C. reinhardtii strain, which can produce the active ALFPm3 driven from P. monodon, providing a potential strategy to use C. reinhardtii as the cell factory to produce antimicrobial peptides.     

Comparative effect of advanced soy products or corn protein concentrate with porcine meal on growth,body composition,and distal intestine histology of Florida pompano,Trachinotus carolinus

The present study was designed to investigate the effects of diets containing advanced soy products (enzyme‐treated soy and fermented soy) or corn protein concentrate (CPC) in combination with porcine meal (PM) to completely replace poultry byproduct meal (PBM) on growth performance, body composition, and distal intestine histology of Florida pompano, Trachinotus carolinus. Four experimental diets were formulated to be isonitrogenous and isolipidic, to contain 400 g/kg crude protein and 80 g/kg lipid. A reference diet (PBM diet [PBMD]) contained 150 g/kg PBM and 495 g/kg soybean meal (SBM), and three test diets were formulated replacing PBM with 15 g/kg of CPC (CPC diet [CPCD]) or replacing all SBM and PBM with 535 g/kg fermented soy (fermented soybean meal diet [FSBMD]) or 451.3 g/kg enzyme‐treated soy (enzyme‐treated soybean meal diet [ESBMD]). All three test diets were supplemented with 38 g/kg of PM. Diets were fed based on a percentage of bodyweight adjusted after sampling the fish every 2 weeks to triplicate groups of Florida pompano juveniles (mean weight 8.06 ± 0.22 g). After 8 weeks of feeding, fish fed CPCD and ESBMD performed equally well in terms of final body weight, thermal growth coefficient, and percentage weight gain in comparison to fish fed PBMD. In all cases, feeding FSBMD resulted in poor feed conversion and lower feed intake compared to other treatments. Protein retention efficiency, whole‐body proximate composition, phosphorus, sulfur, potassium, magnesium, calcium, sodium, and zinc contents were not significantly influenced by the dietary treatments. The results obtained in the present histological study showed no significant differences in the thickness of serous layer, muscular layer, and submucosal layer of the intestine among treatments. Fish fed CPCD showed a significant widening of the lamina propria with an increase of cellular infiltration and higher presence of goblet cells compared to other dietary treatment. Based on these results, 451 g/kg ESBM or combination of 150 g/kg of CPC and 495 g/kg SBM supplemented with 38 g/kg PM can be utilized to develop a practical diet for juvenile Florida pompano without impacting growth, nutritive parameters, and several distal intestine health parameters.     

Bamboo NiR gene is associated with regeneration capacity

It was reported that the activity of NiR (nitrite reductase) enzyme encoded by the NiR gene was correlated with the regeneration ability in rice. To testify the function of NiR gene in bamboo, seven bamboo species whose calli had different differentiation rate were chosen to analyse their NiR enzyme activity. The results showed that bamboo NiR enzymatic activity had a certain correlation with the regeneration capacity. A NiR gene named DhNiR from Dendrocalamus hamiltonii with high regeneration capacity was cloned. Sequence analysis revealed that the ORF of DhNiR was 1779bp encoding 592 amino acids. Overexpression of DhNiR in rice reduced the time of shoot differentiation and increased the transformation rate, suggesting that DhNiR might play an important role in the regeneration ability of bamboo, and can be applied in regeneration and gene transformation of bamboo and other plant species.     

鸡传染性法氏囊病间接ELISA诊断试剂盒的研制及初步应用

采用vero细胞增殖的IBDV抗原建立了间接ELISA，用于定量检测IBDV抗体。对该方法进行了标准化研究，确立了该方法的最佳工作条件。在此基础上研制了相应的诊断试剂盒，并对盒内各组分的性状、保存、质量控制以及诊断试剂盒的特异性、敏感性、可重复性、符合率、与国外同类产品的比较、保存期等进行了全面、详细的研究。结果表明，研制的试剂盒在-20℃保存至6个月时各项性能都很好。该试剂盒与进口试刺盒对同样血清样品检测，符合率为86．7％。间接ELISA试剂盒与琼扩试验的符合率为92，5％。该试刺盒可对大量血清样品进行检测，操作简单方便、结果特异性强、敏感性高、快速，更适合于大型鸡场IBD免疫抗体水平的监测及现地疫病诊断等需要。     

安徽省鸡常见病毒性肿瘤病的检测与调查

应用已建立的鸡肿瘤病快速鉴别诊断技术对源自安徽省5个不同地区的46个鸡群的肿瘤病、抑制病疑似病、死鸡305羽进行检测。结果表明,马立克氏病的阳性率为39．34%(120/305),禽网状内皮组织增生征阳性率为8．52%(26/305),禽白血病阳性率为2．624%(8/305)；另对17群未进行MD免疫的肉鸡进行随机抽样检测,其中5个鸡群检测出马立克氏病病毒强毒,阳性率为29．41%(5/17),阳性群的平均检出率为24 %。     

马传贫驴白细胞弱毒疫苗株跨膜蛋白主要免疫决定区基因的克隆与表达

从感染驴白细胞的马传贫驴白细胞弱毒疫苗株前病毒DNA中克隆了编码跨膜蛋白主要免疫决定区(TMIR)的基因，并在大肠杆菌中进行了表达。所表达的融合蛋白有一部分是可溶的，其氨基端带有6个组氨酸的标签，因此可以用固定化金属离子亲和层析法在非变性条件下进行纯化。在间接酶联免疫吸附试验(ELISA)和免疫印迹试验中，重组的TMIR蛋白可与马传贫阳性血清样品发生反应，而与健康马血清无任何反应。这表明该重组蛋白具有良好的抗原性和特异性，可用于马传贫弱毒疫苗株在体内外复制、接种马体内免疫应答及马传贫诊断的研究。     

外源复合酶对移地保护圈养马来熊日粮营养消化率的影响

利用外源复合酶对移地保护圈养的 9只马来熊日粮营养物质及能量消化率进行了测定 ,经单因子方差分析结果表明 ,在圈养马来熊日粮中添加一定量的外源复合酶 ,能提高马来熊对日粮营养物质的消化率 ,其中 ,添加 0 3%饲料量的酶能显著提高日粮粗蛋白的消化率(P <0 0 5) ;添加 0 5%的酶 ,能显著提高日粮粗纤维、粗蛋白质消化率 (P <0 0 5)。此研究结果可应用于马来熊的饲养中 ,提高其饲料报酬     

鸡实验性急性有机磷中毒血清酶活性变化分析

选取临床健康体质量为0.8±0.07kg的三黄肉鸡24只,随机分成3个试验组和1个对照组,每组6只,其中试验、和组分别皮下一次注射氧乐果攻毒,剂量分别为35mg/kg体质量、70mg/kg体质量和140mg/kg体质量;对照组注射生理盐水。攻毒后系统观察动物急性有机磷中毒症状,采血测定体内胆碱酯酶(CHE)、碱性磷酸酶(ALP)、乳酸脱氢酶(LDH)、谷丙转氨酶(ALT)以及谷草转氨酶(AST)的活力。试验结果表明:鸡急性有机磷中毒主要表现为精神沉郁,共济失调,口角大量流涎,呼吸困难,严重腹泻和粪便带血等临床症状。攻毒组CHE3活性显著低于对照组,ALP的活性也有所降低,LDH活性升高,但ALT和AST的活性无显著变化。     

补饲不同配方酶制剂对犊牛断奶后生产性能的影响

选择健康无病、6- 7月龄间断奶的公牛犊 30头 ,随机分成 3组 ,即对照组 CK、试验组 TE1和 TE2 ,每组 1 0头。对照 CK组饲喂基础日粮 ;试验 TE1和 TE2 组分别补饲0 .1 %由纤维素酶、果胶酶、蛋白酶与淀粉酶组成的酶制剂 E1和由木聚糖酶、果胶酶、蛋白酶与淀粉酶组成的酶制剂 E2 ;试验 60 d,测定加酶对生产性能的影响。结果表明 ,与 CK组相比 ,TE1组日增重提高 7.51 % (P<0 .0 5) ,混合精料、粗料与增重比各下降 7.0 0 % (P<0 .0 5)、1 .2 3% (P<0 .0 5) ;TE2 组增重提高 4.2 0 % (P<0 .0 5) ,混合精料、粗料与增重比各下降 3.86% (P<0 .0 5)和 0 .31 % (P>0 .0 5) ;试验组犊牛断奶后对粗饲料的适应性有所增强 ;两组酶配方中 ,以纤维素酶为主的 E1效果优于 E2     

左旋肉碱对生长肥育猪消化酶活力的影响

用分别添加0、50和100mg/kg 左旋肉碱 (L—肉碱 )的饲粮 ,饲喂“杜大长”三元猪。试验结束屠宰收集十二指肠内容物、血液和肝脏等样品。实验结果表明 :与对照组相比 ,50、100mg/kg肉碱处理提高或趋向于提高十二指肠内容物总蛋白酶、脂肪酶和淀粉酶活力 ,其中100mg/kg肉碱组显著提高总蛋白酶63.49 % (P<0.05)、淀粉酶活力285.85 % (P<0.05)、脂肪酶活力360.86 % (P<0.01)。肉碱处理刺激肝脏酮体生成 ,促进脂肪酸β-氧化利用 ;50mg/kg和100mg/kg肉碱处理使血清β-羟丁酸分别趋向升高 (P>0.05)和升高27.80 % (P<0.05) ;肝β-羟丁酸浓度提高9.80 % (P<0.05)和16.95 % (P<0.01)。结论 :肉碱处理促进脂肪酸氧化 ,用利于机体蛋白质沉积 ,增加消化酶的分泌 ,提高消化酶活力 ,改善生长肥育猪的消化性能。