Hu Hong, Dai Sifa, Wen Aiyou, Bai Xi
College of Animal Science, Anhui Science and Technology University, Fengyang 233100, China.
Animals (Basel). 2019 Feb 20;9(2):65. doi: 10.3390/ani9020065.
The aim of the present study was to improve the expression level of xylanase (XynB) in through a codon optimization strategy and evaluate its effects on the growth performance and carcass characteristics of broiler. According to the codon bias of genome, the gene from was optimized and synthesized by whole gene assembly to improve its expression level in . Approximately 180 target mutations were successfully introduced into natural . The maximum activity of xylanase (optiXynB) secreted by pPICZaA-optiXynB was 1299 U/mL after 96 h induction. Purified recombinant optiXynB had the molecular weight of 24 kDa. The optiXynB presented highest activity in pH 5.0 and 50 °C. The recombinase was highly specific towards birchwood xylan, beechwood xylan, and oat-spelt xylan. In the broiler experiment, a total of 200 Arbor Acre broilers (one day old) were randomly allocated into four groups fed with basal diets containing 0 (control group), 500, 1000, and 1500 IU/kg optiXynB. Dietary 1000 and 1500 IU/kg optiXynB significantly increased ( < 0.05) final weight and body weight gain; dietary 500, 1000, and 1500 IU/kg optiXynB significantly increased ( < 0.05) pre-evisceration weight, dressed percentage, and eviscerated weight compared with the control group. Inclusion of optiXynB in broiler diets linearly increased final weight, body weight gain, breast muscle weight and leg muscle weight, but linearly decreased feed conversion rate ( < 0.05). Furthermore, inclusion of optiXynB in broiler diets linearly and quadratically increased pre-evisceration weight, dressed percentage, and eviscerated weight ( < 0.05). The recombinant optiXynB from pPICZaA-optiXynB was beneficial in improving growth performance and carcass characteristics of broilers.
本研究的目的是通过密码子优化策略提高木聚糖酶（XynB）在[具体生物名称未给出]中的表达水平，并评估其对肉鸡生长性能和胴体特性的影响。根据[具体生物名称未给出]基因组的密码子偏好性，通过全基因组装对来自[具体生物名称未给出]的[具体基因名称未给出]基因进行优化和合成，以提高其在[具体生物名称未给出]中的表达水平。大约180个目标突变成功引入天然[具体基因名称未给出]。pPICZaA-optiXynB诱导96小时后分泌的木聚糖酶（optiXynB）的最大活性为1299 U/mL。纯化后的重组optiXynB分子量为24 kDa。optiXynB在pH 5.0和50℃时活性最高。该重组酶对桦木木聚糖、山毛榉木聚糖和燕麦-斯佩尔特木聚糖具有高度特异性。在肉鸡实验中，总共200只（1日龄）爱拔益加肉鸡被随机分为四组，分别饲喂含0（对照组）、500、1000和1500 IU/kg optiXynB的基础日粮。日粮中添加1000和1500 IU/kg optiXynB显著增加（P<0.05）了末重和体重增加；与对照组相比，日粮中添加500、1000和1500 IU/kg optiXynB显著增加（P<0.05）了宰前体重、屠宰率和去内脏体重。在肉鸡日粮中添加optiXynB可使末重、体重增加、胸肌重量和腿肌重量呈线性增加，但饲料转化率呈线性下降（P<0.05）。此外，在肉鸡日粮中添加optiXynB可使宰前体重、屠宰率和去内脏体重呈线性和二次曲线增加（P<0.05）。来自pPICZaA-optiXynB的重组optiXynB有利于提高肉鸡的生长性能和胴体特性。
